How to Build a 3D Printer (The Ultimate Guide)

[Music] [Music] [Music] [Music] [Music] [Music] dr. D flow my name is dr. D flow and today I'm going to show you how to build a 3d printer I've always been a strong advocate for building a 3d printer from either a kit or cell source parts instead of purchasing a fully assembled one I recommend this route and then only because you may save some money but also because you will have a greater understanding of how your printer works one of my mottos is that if you can build it and you can fix it and trust me 3d printers require a lot of maintenance in a sentence this video is people who want to learn more about the components that make up a 3d printer and how to select these components to build or modify a printer to help illustrate some of my points we'll be walking you through the build of xenix zayed x is a compact 3d printer that features two extruders that operate independently of each other there are many benefits to this design over printer with fixed dual extruders which we'll discuss later if you're new to 3d printing don't let the dual extruder stare your way I intend for this video to provide more general information on building a 3d printer it'll be your choice to determine how many extruders you want to include I found the unique design of zayed X to be a great teaching tool it's used to three different rail profiles for the X Y and z-axis will motivate our discussion on linear rail the undeniably small print bag will be a great segue in discussing 3d printer design criteria a couple more comments before we get started if you want to build this printer exactly to my specifications and on my website is a bill of materials and a step-by-step guide with pictures personally I find a text and picture manual format easier to follow than a video especially when it comes to building something this complex but let me know your thoughts this printer was designed by Steven and the appropriate links are below for the original design that's unmodified by myself I'm not gonna pretend that building a 3d printer is quick as a result this is going to be a long video to make it more digestible it is broken up into standalone sections each section will begin with a general explanation which would help the newcomer get a feel for some of the considerations and requirements for designing and building a 3d printer he'll then proceeded to provide too much information at the risk of boring you use a table of contents in the description to jump around at topics that you are most interested in with that all the way let's get started our first topic is linear rails but I wanted to give a brief overview of the type of printer we're building ZX is a few step addition modeling or FDM 3d printer this is the most common type of 3d printer at the hobbyist level to oversimplify in FDM 3d printer is really just a fancy hot glue gun that can be moved accurately in three dimensions for a standard Cartesian 3d printer we require at least one linear rail per dimension there are other types of 3d printers that operate on different coordinate systems but we are not going to worry about those today if we compare the linear rails of the design X with my commercially available make your m2 you will notice the m2 rails are fastened to the metal frame while the sinx rails play a dual function as both the rails and the frame both of these approaches have their pros and cons but it is unrealistic for a hobbyist to build the m2 frame however the design X rails are like an adult version of connects which can easily be connected to each other to form a coordinate system V rails are a specialized form of tena aluminum extrusion the t-nut is what allows the V rails to be joined together in an infinite number of configurations I present to you the meaning of life I assemble this piece of abstract art in about five minutes but I'd be willing to part ways with it for a cool five thousand dollars all jokes aside this rail is quick to assemble and work with other components such as this rod plant which of course allows a linear rod to be joined with the aluminum extrusion it's important to keep in mind that not all T solid extrusion is set up to handle linear motion V rails can accept tea nuts but also have a smooth V groove hence their name that matches the contour of a chamfered wheel known as you guessed it a V wheel to add the confusion my CNC router made by the company inventables uses a different type of linear rail known as maker slide now maker slide is still technically t-slot aluminum extrusion but it doesn't work with the previously mentioned chamfered wheels it needs its own special wheel not only do you to make sure that your rails are set up for the near motion but you all seem to make sure that you've got the correct wheel that's going to ride on the rail there remain different profiles and lengths of view the site X uses four different profiles of URL which I have purchased from the online retailer open builds the four profiles used are 20 by 20 20 by 40 20 by 60 and CB usually the aluminum extrusion is named after its cross-sectional dimensions hence 20 by 20 is 20 millimeters by 20 millimeters of course the CVM is an exception to this rule due to its shape but the increased cross-sectional area of the C beam it makes it more rigid and better suited for applications where the motion has to overcome resistance like in CNC routing or an end mill has to cut through material further each rail profile has its own set of compatible plates these plates become carriages when you add V wheels to them of course wider rails will support larger plates allowing for larger objects to be mounted and moved more stable e-even though aluminum is relatively light CNC machines manifold aluminum extrusions become heavy quickly and 3d printing where the forces resisting movement are relatively low smaller aluminum profiles can be used to save money and weight you know turned it to linear rails are linear rods in the context of 3d printers it might even be appropriate to say that linear rods were predecessors for linear rails at least at the hobbyist level a couple years ago it seemed like every 3d printer relied on rods for linear motion this is for good reason quality rods are more affordable and more available than linear rails but most importantly the linear motion bearing that rides on the rod is significantly cheaper than the wheels that are right on the V rail or the ball bearing carriages that ride on a normal rail I'm talking pennies on the dollar we will cover V rail carriages in the next section with the cost being more is there a reason to choose rails over rods and well yes linear rails have their own set of benefits like the fact that they only allow for one degree of freedom for example this carriage will only move forward and backwards and it will not rotate around its axis of travel this is unlike a linear rod where the bearing will move back and forth but it will also rotate around its axis of travel this is the reason why the demo has two linear rods it prevents the carriage from rotating now I know this section is supposed to be about linear rods and I'm talking about the benefits of linear rails but I think that talking about the benefits of linear rails illuminate some of the shortcomings of the rods and why many di wires are moving away from linear rods in favor of linear rails let me discuss one more benefit of using a linear rail over a linear rod and that is the ability to support the linear rail at any point along its path so for example have supported this rail at both ends but also in the middle this middle support does not impede the motion of the carriage this third support would make the axis you know stiffer overall now only the ends of the linear rod can be supported if I were to you know produce support here mimicked by my fingers this would actually impede the movement nevertheless because linear rods have been used in 3d printing for so long there are so many designs that have successfully used them the Prusa i3 printers are some of the most popular printers on the market and all three axes use linear rods and the prints are phenomenal what has really piqued my interest as of lately are 3d print designs that are using carbon fiber tubes as linear rods I bought a couple of them and man these tubes are light and rigid the one issue is that the outer diameter of readily available carbon fiber tubes is low irregular causing a lot of friction as the linear bearing moved across it to allow for linear bearing to move smoothly you'd have to sand the carbon-fiber tube but you need to be very very careful when sanding carbon fiber or even cutting it because there's particulates are hazardous one of the reasons that ZX doesn't use linear rods is because the linear rods have to be clamped to the frame now these clamps cause the rods to be about two centimeters offset from the frame as you can tell is a very compact build and there's not clearance for that extra 20 millimeters on both sides you can see how close the exteriors are I think there's about a centimeter between them because idec's doesn't use linear odds they probably won't be mentioned again in the video but when you're looking online you're gonna see a lot of designs that call for the use of linear odds don't think anything less of them just because I'm not using them as promised our next topic are the via rail carriages we need a carriage or cart to ride on the rail to provide the actual motion this topic wouldn't be as lengthy if we were talking about the ball bearing carriages used to make of your m2 now you just simply slide the carriage on the rail and that's it if there's too much play in the carriage well you're gonna have to ask for a replacement from the manufacturer if the replacement still Wiggles too much well then you're gonna have to fork up some more cash and purchase a more accurate set of carriages and rails the point here is that this system is not adjustable however the opposite is true for the V rail system usually purchase a plate and wheel separately although kits do exist all plates allow for at least four wheels to be attached and some allow for more in our first example we had eight wheels more wheels means more points of contact which means a stronger overall assembly however more wheels also means increased friction that your motor has to overcome so there's a trade-off there here's the big question if di wires are installing their own wheels how can manufacture errs ensure that all carriages fit snugly on linear rail any wobble my carriage would be disastrous to the final resolution of the printer well if you can't make it perfect then make it adjustable the eccentric spacer is the magic sauce for this whole system of linear motion let me explain if you notice the bore for the eccentric spacer is not in the center hence eccentric not concentric the eccentric spacer has a flange which mates with the appropriate hole in the plate the magic behind the eccentric spacer is actually pretty simple here I pushed a bolt through the back of the plate and through the board the eccentric spacer obviously the bolt is going to follow the bore the space so here it's pretty close to this edge over here but if I rotate this space there 180 degrees now it's followed that bore and it's closer to this edge over here so effectively what does this mean well if we put a wheel on there then we can actually you know move the position of the wheel either away from this edge or towards this edge now if we stick a bolt on the other side and a normal spacer and in their wheel I'm gonna reset this bolt so that it's as far to this edge as possible I'm gonna add some nuts so everything doesn't go flying around so here if we slide a rail through here I don't know if you can tell but the wheels don't rotate as the rail moves it's a very very loose fit between the rail and the wheels so what we can do is move this eccentric spacer really either way to bring the wheel closer to this edge now you can see that moving the wheels moves the rail a common question is how tight to the wheels grip the rail and it's all about the index finger the wheel should be loose enough that you can spin them with your index finger but they should be tight enough so that the wheels don't spin freely there should be some kind of proportional movement in the carriage as the wheels move after installing the wheels I recommend pushing the carriage along the full length of the rail you plan to use if you notice that some sections of the rail it's easier to push the cart than others well then there could be an issue with the rail or wheels it's better to find out now that there's a dent in a wheel or that the rails a little bit warped and to find out after we install the belts which we do next as I set up for a next topic on transmission I've created this little demo where all three motors are instructed to go forward then reverse the same number of rotations by the end of this section you'll understand all three configurations and why the bottom plate covers the least amount of distance the components that allow for the rotation of the motor to move the carriage linearly is where I'm collectively referring to as a transmission here's a quick primer on the two systems which are predominantly used in CNC machines belt driven and lead screw driven transmission let's talk about belt driven linear motion a timing belt has teeth and these teeth will mesh with an appropriate timing pulley the pulley in turn has a center bore which can accept the shaft of a stepper motor when the severed motor rotates it rotates the pulley which moves the belt now how do you think the size of the pulley influences the distance the belt moves per rotation of the motor shaft we will discuss the impact a pulley diameter in a bit for what I would call a traditional loot belt style we need a pulley on the opposite end of the motor this pulley is known as an idler pulley because it spins freely it has two functions one it acts as a belt tensioner and two and make sure the belt remains in position and other belt setups the belt is fastened at either side of the rail this configuration usually signifies a belt and pinion linear drive system look at how the motor moves with the carriage all the two belt configurations the closed loop setup is the most common in 3d printing in fact I don't think I've ever seen the 3d printer use the belt and pinion setup and this is largely because the motor attached to the carriage is going to change the inertia of the carriage ultimately make the carriage more resistant to acceleration so this is a great set up to use when speed is not as high our priority like it is in 3d printing now the Scitex uses the closed-loop belt configuration for three OS axes both of the X and the y I mentioned that the pulley and the belts need to be at the same specification in order to mesh and operate properly you can tell all the way over there that this belt and pulley combo does not work however this may be less obvious when purchasing them separately on a website like Amazon without getting too far into the weeds there are three specifications that you will need look out for when buying timing belt and their matching pulleys the first is the pitch the pitch is the distance from the center of one tooth to the next the second is the tooth profile on the teeth trapezoids or semi circles and the third is the width of the belt unfortunately for all of us Tommy Belt nomenclature is a disaster so the best way to make sure a belt matches a pulley is to check the three aforementioned specifications for both the belt and the pulley so if there's such a variety and timing belts that exist what specification should you go with well for small CNC machines in 3d printers the GT tooth profile of timing belts is the way to go many people mistake the number directly following a GT to be the pitch of the belt for example you can purchase a gt2 or gt3 timing belt the two and three refer to the design iteration of the GT series and not the pitch as some may think the gt3 timing belt was released after the gt2 belt and is constructed from a new composite material to increase its load rating however pulleys designed for a gt2 belt will mesh perfectly with the gt3 belt and vice versa I say stick with the gt2 belt because it is cheaper and can always be switched out for a gt3 later depending on the retailer the pitch and belt width will either be found in the name or the description I would say that 95% of 3d printers use a belt width of five to six millimeters in a pitch of two millimeters overall belt driven transmission is cheap fast and accurate enough for 3d printing so why is the site ex use a lead screw driven transmission for its z-axis to answer this let's quickly discuss how this form of transmission works usually a stepper motor is connected to a lead screw through a coupler as the stepper motor spins the lead screw a nut block will move up and down the leads grille this is fairly analogous to the normal mechanism behind a nut and bolt however unlike a typical threaded rod found at your local hardware store the leash group has special threading to minimize backlash and allow for low transfers without jamming this is fancy lingo for saying the lead screw can move objects smoothly and accurately I do want to quickly elaborate on the term backlash because one it will affect the accuracy of the linear motion and two anti backlash is a common feature when shopping for some of these linear components both belt and leadscrew systems have backlash or lost motion caused by gas between the pulley and belt teeth or the lead screw and nut threading when reversing directions this lost motion or slack must be taken up before the carriage starts to move for 3d printing or accuracy and repeatability are important we should try to minimize the amount of backlash by selecting the correct components enter the anti backlash nut this nut screws on the leaves screw like a typical nut however a set screw can be installed to apply a preload to the nut by flexing this upper portion this effectively minimizes the slack or backlash when reversing directions trust me as I tighten down this set screw this nut will ride on this lead screw much stiffer you can actually feel that there is less play if I tell this stepper motor to rotate you'll notice two things the first is that the nut block just rotates it's not moving linearly the second thing you'll notice is that the lead screws wobbling now we can fix both these things the first thing is is that we need to stabilize the nut block so basically if we prevent it from rotating now you can see it's moving up and down the wobble can be fixed by stabilizing both ends of the lead screw it's kind of hard for me to do it with my hands I'm not gonna walk you through how this setup accomplishes what my hands just did so first off the nut block is attached to carriage the carriage has wheels that are riding along and inside the track and they're actually going to be resisting the nut blocks tendency to rotate at the end of the lead screw there are bearings and these bearings stabilize and prevent that wobbling my demo here uses a four start Acme lead screw with the pitch of two millimeters and a lead of eight millimeters I feel like I've already bored you guys with belt specifications so I'm not going to break down these dimensions I would say that it is better for beginners to purchase a set that includes both the nut and a lead screw to ensure compatibility nine out of ten times if you search 3d printer lead screw on Google you will end up with the same one that I have overall lead screw based transmissions are more accurate than belts but are slower and more expensive however the increased accuracy is that the main reason Acme lead screws are commonly seen on the z-axis of 3d printers Acme lead screws are unlikely to spit on their own which means when we cut the power to the printer the carriage is not going to drop to the bottom here I've set up a demonstration showing that this won't hold true for a belt configuration I've added a little bit of weight to the carriage and I've unplugged the motor if I turn it sideways to simulate a z-axis you'll see that the carriage drops worst case scenario your hot end crashes into your print I've unplugged the stepper motor and added the weight to the lead screw setup as you can see nothing's moving but obviously this is an apples-to-apples comparison you guys already know that this carriage has eight wheels so more friction however you have to believe me that the lead screw is providing a majority of the stability and preventing this carriage from dropping when the power is cut to the motor the astute will notice that the z-axis motor is not directly drive the z-axis lead screw instead the motor drives a smaller pulley which in turn drives a larger pulley this pulley configuration will actually increase the resolution at which the z-axis moves this makes sense because one turn of the motor shaft and hence the smaller pulley will result in only a partial turn of the larger pulley that has connect to the z-axis leadscrew this configuration will lead to increased torque but at a cost of lower speed how do we calculate the speed at which the lead screw rotates compared to the motor shaft rotation great question for this calculation we need the gear ratio this is determined by dividing the number of teeth on the driven pulley which is the larger pulley in this example by the number of teeth on the driver pulley which is the smaller one that is connected to the shaft of the motor because the larger pulley has 60 teeth and the smaller one has 16 teeth the gear ratio would be 3.75 this ratio means that the smaller driver gear must turn 3.75 turns to get this larger driven gear to make one complete rotation therefore the lead screw will always turn 3.75 times slower than the speed of the stepper motor the opposite would be true if the pulley sizes were reversed the main purpose of this configuration is not to mess around with the resolution but instead to relocate the stepper motor from the top to the side this makes an overall lower profile 3d printer it should be noted that most 3d printers don't have this drive chain the only pola you typically have to worry about is the driver pulley in the closed-loop belt configuration this pulley usually has 16 or 20 teeth let me reintroduce the demo before we discuss the optimal teeth the driver pulley should have as promised we're going to discuss why the plate that is attached to the lead screw cover a significantly less distance compared to the two belt configurations even when the motors are programmed to rotate the same number of times I have programmed the motor to complete one revolution let's see how far it goes my indicator says the plate moved about eight millimeters I know I said I wasn't going to go into details on the leadscrew dimensions but remember what I said this demo uses a four start Acme lead screw with a pitch of two millimeters in a lead of eight millimeters while the lead of a screw is the linear distance traveled for each complete revolution of the screw so eight millimeters checks out now let's repeat the same measurement for the belt configuration omni's my calipers because the distance traveled is going to be too far from my indicator to measure I have made a little black mark here as the starting point for our measurement the pulley over here has 16 teeth I will have a motor perform one rotation and then we'll see how this distance compares to the lead screw configuration as you may or may not be able to see this is 32 millimeters does this 32 millimeters and movement make sense for the one revolution of the pulley well this calculation is actually pretty easy if you recall we're using ADT two timing belt with a pitch of two millimeters because the pulley will match the tooth profile of the timing belt all we have to do is multiply 16 teeth by two millimeters to determine the circumference of the inside portion of the pulley that will mesh with the belt so 16 times 2 is 32 again the math checks out let's switch out this 16 to 4 a 20 to pull II how far do you think one revolution of the 22 Polly will move the carriage if you guessed forty millimeters then you have picking up what I'm laying down by increasing the tooth count by just four from 16 to 20 teeth the carriage will move 20% farther which also means the carriage moved 20% faster because the motor rotated at the same speed for both pulleys the math checks out but I still think it is very interesting how only a couple of teeth can have such an impact on speed now what is the trade-off for speed if you know this then we're really on the same page it's resolution the more teeth the more the resolution decreases now it's important it's like the pulley that will optimize the performance of your 3d printer however it really isn't that big of a deal to use a pulley with 20 teeth instead of a pulley with 16 teeth the difference in resolution is only a couple of microns what is important is to know how the rotation of the motor translates to the distance moved by the carriage and millimeters this conversion from rotation to linear movement will be needed when configuring the 3d printer installing a pulley with 20 teeth and thinking is appalling with 16 teeth could result in your prints being often dimensioned by 20% let's discuss the stepper motor and then we can finally start assembling this printer if the extensive nuts are the magic sauce and the stepper motors are the chicken nuggets the accuracy and reliability of a stepper motor at such a low cost has facilitated the widespread availability of 3d printers and really any low-cost CNC machine further the operating principle behind an open-loop stepper motor is simpler than the alternatives discussing house or motor works and all the criteria that goes into picking one out it's going to give us plenty to do in this section we will discuss wiring and programming stepper motors a little bit later on fortunately the NEMA stepper motor standard has made it much easier to find and purchase motors that will fit your printers design searching stepper motor on Amazon or return mini silver and black sub promoters that have NEMA in the title followed by a number that number refers to the faceplate size of the stepper motor for example a NEMA 17 motor will have a faceplate approximately 1.7 inches by 1.7 inches equally as important all name is 17 motors will have the same layout of mounting holes which means that you can virtually swap out any two stepper motors that fall within the same NEMA what isn't specified by this standard is the depth or the length of the stepper motor or if the shaft is geared here I have two NEMA 23 stepper motors this one is much longer than this one we're going to take both of them apart and see what's accounting for this difference in length but first a quick stepper motor introduction a stepper motor differs from a DC motor than is found in drills and fans of the main difference is the one that stands out in the context of CNC machines is that if I supply power to the DC motor I have no idea how many times are rotated between when I switched it on and when I switched it off if you're watching this video sequentially then you will know that in the transmission section I made a big deal about knowing how far the carriage moved for each rotation of the motor shaft this important conversion from rotational to linear distance would be meaningless if we can't precisely control the motor shaft there are ways to get rotational feedback from a DC motor this is usually accomplished by attaching a device known as an encoder to the shaft I don't have an example in front of me but I can explain the premise the encoder and the motor operate in what is known as a closed loop a microcontroller such as an Arduino turns on the motor and checks in with the encoder until the motor has rotated the specified amount for all intents and purposes this configuration is expensive and complicated but it's found in premium 3d printers most of which are not fused filament 3d printers like the one we're building stepper motors on the other hand operate in an open-loop configuration open means that we don't need an external device to check the stepper motors position it'll become more clear why this is in a second when we power up a stepper motor it doesn't spend freely like a DC motor it actually takes a coordinated effort by device known as a stepper driver the stepper driver sequentially sends varying amounts of current through the four wires the stepper motor this orchestrated effort results in the stepping of the motor shaft if we step the motor fast enough the shaft will appear to rotate continuously even though the rotations comprise screech steps a quick peek inside the stepper motor will show us what these wires are supplying current to as I'm taking apart this stepper motor I need to fill you in on some lingo the parts that rotate are collectively called the rotor while the parts that remain stationary make up the stator there are a couple different types of stepper motors but we are focusing on the hybrid stepper motor this motor combines the designs of permanent magnet stepper motors and variable reluctance stepper motors the hybrid stepper motors comes in two flavors a unipolar and bipolar you can tell the difference between a unipolar and bipolar stepper motor by the lead or wire count the unipolar has 5 or more wires while the bipolar has 4 wires because the stepper motor that we are currently operating on has 4 wires it is safe to assume that the bipolar hybrid stepper motor will be the star of this segment I wish I had time to discuss all the different types of stepper motors but this video is borderline feature film length the bipolar hybrid sepra motor is the most popular and the most compatible with all 3d printer electronics so it's a great second order to learn about or probably jumps out to you first is the bright copper coils of the stator the wire supply the current which energizes the copper coils creating an electromagnetic field the direction of current flow and how the coils are wound will determine if the coils act as a north or south pole more formally this is known as the coils polarity as you're probably already aware for wires is only enough for two independent circuits with their clearly being more coils and there are wires some of the coils must be in series or parallel with each other in fact every other coil is in the same circuit the correct terminology here is that every other coil is on the same phase now maybe based on the way these wires separate you would think that the blue and green wires will be part of the same phase and the red and black wires will be part of the same phase this is actually not the case I brought down my multimeter and said to continuity mode you know beep when there's an electrical connection between two conductors so it should be if I found two wires they're part of the same phase if I connect the blue and green wire to my multimeter there's no beeping if I connect the blue and red wire there is beeping so that means there's continuity and the blue and red wire are on the same phase and by process of elimination the green and black wire supplied the second phase I always recommend when you buy a stepper motor to check which wires belong to which phase you don't actually have to open up the stepper motor to do this you just need a multimeter you'd be surprised how the color schemes differ between manufacturers I am providing all the information here not for you to memorize but to emphasize that the way in which a stepper motor is wired and eventually connected to the printer motherboard is important mostly because of the two separate phases in a direction of current flow and how that will affect the polarity of the coils we will continue talking about wiring when we actually hook up the motors to the printer motherboard next let's take a closer look at the rotor sandwich between the two bearings on the rotor is a large permanent magnet the permanent magnet is divided into two sections the top rotor Cup and the bottom murder cup these cups have opposite polarities we'll talk a little bit more about these teeth or grooves that are in the rotor cups but first I want to talk more about the discrete steps taken by the CEMP remoter before circling back and talking about how the step size is in part dependent on the rotor teeth this step is the reason why the stepper motor can operate accurately without positional feedback this is because each step rotates the shaft a precise number of degrees the most common full step size is 1.8 degrees therefore it would take this motor 200 steps to complete a rotation to hammer this point home here's the demo from the transmission section we still have the 22 team stall to the stepper motor this stepper motor is a 1.8 degrees to promoter if I told that stepper motor to take 300 full steps and the shaft would rotate one and a half times with each complete rotation of the pulley equalling 40 millimeters of belt travel distance we derived this number in the transmission section the carriage would move 60 millimeters if I told the stepper motor to move another 300 volts it would move another 60 millimetres stepper motor movements are very precise I have to keep using the word full in front of step because stepper motors can take half steps or operate in even smaller increments notice micro stepping micro stepping will have its own section because it not only affects accuracy but also the noise level of 3d printing so how does this DEP remoter move precisely 1.8 degrees per full step unfortunately I'm gonna have to leave you hanging on this question because I have to explain even more stepper motor anatomy most of which isn't critical information for learning how to operate or build a 3d printer there are however a lot of great YouTube videos that address this question and I will link to them below when I can quickly show you is it the number of steps it takes for a full rotation is in part dependent on the number of teeth on the rotor the rotor has 50 teeth and moves 1/4 of a tooth pitch per step as the stator phases are energized hence 50 times 4 equals 200 steps per rotation and then 360 divided by 200 equals 1 point 8 degrees I'm not going to leave you hanging on why these 2 NEMA 23 stepper motors have different lengths let's go ahead and crack open the big one now and see how it differs from the smaller one that we've already opened up as you can see there are way more rotor cups inside the longer NEMA 23 stepper similar to the smaller rotor the cups alternate in polarity every 2 cups is known as a rotor stack this longer NEMA 23 has four rotor stacks you also notice that the copper windings travel the whole body of the name of 23 so the longer bodied Nemo 23 would have longer copper windings increasing the length of the standard windings as well as increasing the number of rotor stacks will yield a more powerful stepper motor purchasing a longer stepper motor with more than one rotor stack is a great way to get a little bit more oomph or torque out of your stepper motor without having to increase the NEMA size however if you require significantly more torque to move your load and it will be better to increase the frame size of the motor a NEMA 11 is never gonna have as much torque as a NEMA 23 however the amount of torque supplied by a NEMA 23 stepper motor is almost always overkill in a normal sized 3d printer but are commonly used in other CNC machines one of the drawbacks of stepper motors is their power and efficiency went on stepper motors consume current independent of the load therefore a resting stepper motor will consume its max current when given the opportunity that's why it's important to not buy a stepper motor that's too powerful for your application we actually need the middle ground between the powerful and NEMA 23 and the anemic NEMA 11 which happens to be the NEMA 17 for most 3d printers NEMA 17 motors usually hit the sweet spot between torque and power draw one thing that might be a little bit confusing is that one stack NEMA 17 stepper motors exist in a variety of torque specifications each manufacturer uses a different stack length you could probably tell from the deconstruction of the name of 23 stepper motors that the shorter name of 23 had a longer stack length then the longer NEMA 23 here's another one stack NEMA 17 stepper motor it's slightly larger than our first and that's because the stack length and this debra motor is longer for most 3d printers you're going to want your NEMA 17 stepper motor to have between 50 to 60 Newton centimeters of torque I had said way back at the beginning of this section that the NEMA standard also does that specify if the shaft is geared or not here's a NEMA 17 motor that doesn't have a gig shaft this is the one we've been working with and here's one that does as you can see the geared shaft adds a bit of housing to the faceplate this means it's difficult to switch out a non geared supra motor for a geared stepper motor so it's best to consider if you need a gear to different motor in the initial stages of designing or 3d printer why might you need one well dear stepper motors usually have increased torque and resolution of course we're going to take this stepper motor apart to figure out how it works the first thing you will notice is the arrangement of the gears these three outside gears orbit around the center gear appropriately named-- the outside gears are the planetary gears while the center gear is the Sun gear the planetary gears ride around on the ring gear the original NEMA 17 shaft is connected to the Sun gear while the new output shaft is coupled to the planetary gears through these spokes the output shaft will complete one rotation after the play antara gears have gone around the outside during gear once get this the output shaft has five times more torque in the original NEMA 17 shaft this is more torque than the one stack NEMA 23 remember when I made fun of the NEMA 11 and how it will never have more torque than the NEMA 23 well that was technically not true an appropriately geared NEMA 11 stepper motor such as this one that I found in Amazon can have more torque than a NEMA 23 but what's the catch there's always a trade-off recall from the transmission section that the gear ratio tells us how many times the input gear must rotate to get one rotation out of the output gear without going through the derivation the gear ratio of a planetary gear arrangement is a number of teeth on the ring which in our case is 46 divided by the number of teeth on the Sun which again in our case is 11 plus 1 don't forget to +1 this results in a 5.1 8 to 1 gear ratio the NEMA input shaft will have to rotate 5.1 eight times in order to get the gear head shaft to rotate one time it will now take 1036 full steps per rotation when using at 1.8 degree stepper as the input for the gear train from the perspective of the geared output shaft this stepper motor has a 0.35 degree step size I hope this makes it clear why gear heads can also increase resolution however the looming trade-off with geared stepper motors is speed in this example this geared sector motor would operate at less than one-fifth the speed of its uncured brother for this reason geared stepper motors are rarely seen driving carriages on the axes of 3d printers Bo wait there are two reasons I took the time to explain this the first is so that you won't accidentally buy geared stepper motors for the linear rails the second is because gear stepper motors are critical in extruding the filament you would be surprised by how much force it takes to push filament through the hot end we will contain this discussion in the extruder section ok that was a lot to talk about for stepper motors it's time to put everything together that we have learned by buildings INEX the topics we have covered really applied to most CNC machines we still need to discuss a couple more 3d printer specific topics so the extruder and electronics so stay tuned until after the build the moment we've all been waiting for it's time to assemble zai Dex when he first clicked on this video you probably didn't think I was gonna lecture at you for 30 plus minutes but we get to apply all the stuff we learned in building the frame and the linear motion of zai Dex we have all the necessary components rails pulleys belts carriages brackets for actually attaching the rails together stepper motors and yes we have 3d printed parts to build this 3d printer it's a common joke at the first step in building a 3d printer is buying a 3d printer however these 3d printed parts are necessary and keeping the cost of the printer down could you imagine how much would cost machine a component like this it'd be very expensive if you don't have access to a 3d printer online 3d printing services do exist there are many different websites you can upload a printable file to and receive the end product within a week also if you are a student or work at a university then chances are you already have access to a 3d printer I recommend building a 3d printer now for when you don't have access to one after you graduate finally we have the tools needed to assemble the printer as I mentioned way back in the beginning of this video connecting the rails together is actually really easy the only thing that can be a little bit of a hassle is if you need to attach something to the end of the rails and that's because the ends are not tapped so one of the tools we need is a tap besides that everything else is pretty standard we've got allen keys we've got wrenches I'm actually missing a wrench we've got a tape measurer and calipers for measuring and the last important tool we have is a square the square is very important for making sure that the axes are perpendicular to each other if they're not the print is not gonna look very good fortunately I've already built desired X once during the second bill I can reference back to the first build so that you have an understanding of where each parts going to go I only have one more big shout out to the original creator of ZX who was Steven when I saw this printer a couple months ago I was like I've gotta build it the way that he's incorporated dual extrusion setup and small compact form factor was just really interesting to me so interesting I guess I'm going to build a second time I have linked to Stephens original build in the description of this video as well as on my website however I've made a lot of my own changes to this printer so if you want to build my spec you're gonna have to check out my website for a step-by-step guide that's going to show you where each piece goes which bolt to use where you know the works this video is just going to feature a gross overview of buildings idec's and we're really going to focus on you know kind of important concepts that apply across all 3d printer builds especially those that use aluminum extrusion our first order of business is to construct this base that wraps around the bottom of Zhai decks out of these three pieces of aluminum extrusion the base is what the y-axis rests on and what keeps the z axis perpendicular what's kind of a hassle about design X's design is that all the linear rails fall between the commercially available 500 millimeters and 250 millimeter lengths linear rail this means we're gonna have to do some cutting however most 3d printer designs don't deviate from the standard lengths but I guess that's the price we have to pay to be compact aluminum extrusion doesn't give much trouble to a hacksaw but I'm gonna button down so let's automate this process I've been trying to expand the metalworking capabilities of my workshop and I recently acquired this blue jig that turns my porta band into a horizontal band saw this jig is really nice because I can still remove the Porta band if I need to be more mobile or if I need to work overhead anyways let's stop talking let's start cutting this thing's such a beast it needs to be chained up [Applause] I was in a role with the bandsaw so I went ahead and cut all 11 pieces v rail to length to make the base square we're going to use these brackets to connect the V rail as I mentioned before the holes on the ends of the V rail are not tapped so we're going to do that now I recommend doing this free-handed versus throwing it into a Chuck of a drill used to be really careful when you're forming the threads I've attached the plate to the end of the V rail with the tapped holes now to attach the plate to the length of a V rail I have to use a tena to make it a little easier to attach the rails I typically screw on the t-nut first and then slide the nut through the rail you now know how to cut the rail tap the rail and join the rail both at the ends and along the length but the most important thing when building a 3d printer is that the rails are perpendicular to each other at least for the axes and you would be surprised by how much play there is in both the t-nut and the plates sort of make sure that the rails are actually perpendicular to each other we need to check it with a square if you find that your rails are not square like this example well then you can loosen the bolts and adjust it until it is square now it's time to build the y-axis I am using C beam V rail to accommodate the larger carriage that will be used for the build platform if 3d printed component will allow a stepper motor to be attached to the end of the rail that stepper motor is a standard one stack NEMA 17 a 22 pulley with a gt2 profile will stone the shaft of the stepper motor and mesh with the timing belt one end of the timing belt is attached to the bottom of the carriage while the other end snakes through a hole in the part that holds the stepper motor then wraps around the stepper motor pulley returns back through a lower hole before running across the bottom of the rail at the end of the rail this timing belt end is routed around the idler pulley before connecting to the bottom of the carriage to form a closed loop belt configuration as we talked about in the carriage section I rotated the two eccentric nuts to the carriage ride snugly on the rail and that's it the y-axis is attached to the base after checking out of the square I cannot emphasize enough how important these right angles are in building a 3d printer before we start work on the next axis I want to talk about a unique feature of ZX not only do the extruders move independently in the x axis but they also move independently in the z axis ultimately this independent z axis design will allow us to fine-tune the distance between each nozzle and the printbed getting this distance right is critical for successful prints and we will discuss this further in the limits which section next we're going to build the 2 x axis and then we're going to attach them to the z carriages because the clearance becomes tight once we put the z towers up the x axis also use a closed loop belt configuration but on a 20 by 20 V rail which means that we will again use a timing belt pulley and idler pulley what is interesting about the x axis are the use of bearings to prevent the timing belt from rubbing on the edge of the rail because as you will see the timing belt loops behind the me rail while all the washers and bearings can be a lot to juggle when attaching this different motor the routing of the belt behind the rail decrease the footprint of the axis which is perfect for Z X it was important to keep the x axis as light as possible because both z axes will have to lift next axis hence why we are using the smallest V rail [Music] [Music] I am now attaching a x-axis to a Z carriage through right angle connectors I made sure that the faces of the two connectors were Square to the edge of the z-axis carriage therefore when I place the x-axis on these connectors the rail will be perpendicular to the z axis an interesting design element of this printer is that the extrusion drives will ride on separate rails parallel to the x-axis we just built so an extra rail needs to be attached to the opposite side of each z carriage we will talk more about this design choice when we add the extruders and drives to the frame it's time to add the rail for the z-axis to the base prior to filming this I attached 3d printer feet in order to prevent vibrational noise during printing and this additional clearance will give the power supply more airflow because eventually it'll be mounted to the bottom of the base attaching the Z rails should be easy because we took the time to get the base Square so if we snug the Z row up against their respective corners they should be perpendicular to the y-axis and a build platform I know that it looks like there are a lot of components here but a lead screw setup is generally much quicker to put together because you don't have to worry about belt tension in the transmission section I explained the reasoning behind why we are using lead screws instead of belts for the z-axis [Music] [Music] [Applause] [Music] and there you have it the frame is built I know I sped up some of the clips as I was building but in real time the frame only took a couple hours to put together because of how easy it is to work with and assemble I highly recommend using aluminum extrusion for building really any CNC machines with the frame rails assembled it's time to discuss the extruder the extruder is obviously what makes this assembly of linear actuators a 3d printer you may not know this but there are many different types of 3d printing technologies the way in which the extruder heats and liquefies a thermoplastic before depositing it on the build platform is what makes this printer a fused deposition modeling or FDM printer just a quick clarification the term FDM is trademarked by Stratus a large 3d printing company due to its trademark the DIY 3d printer community has rebranded FDM as FFF or fused filament fabrication there's no difference between the terms besides the trademark looking back I should have exclusively used the term FFF for this video because I'm appealing to the maker community but anyways let's get back on topic by going over the anatomy of an extruder we will start from the bottom which is going to be closest to the build platform and work our way up the extruder assembly first we have the nozzle which has a small pinhole or liquefied filament exits from the extruder the size of this pinhole is known as the extrusion diameter the smaller the extrusion diameter the higher the resolution of the prints the smallest recommended diameter is about 250 microns I usually recommend fused filament 3d printers for desires that have a feature size of at least 0.5 millimeters if you need higher resolution stereo lithography is another 3d printing technology that is quickly becoming affordable for the hobbyist and has great resolution nozzles are made out of a variety of different metals such as brass copper steel and tungsten carbide get this there are even gemstone nozzles I don't need it but I want it all these nozzle types have a different wear resistance composite filaments containing hard and sharp particles like carbon fiber and sand will eat away at the inside of the affecting the extrusion diameter I don't usually print with the exotic filaments so I stick with cheap brass nozzles I recently purchased the gold edition of the e3d v6 extruder because some extra but it comes with a hardened steel nozzle so now I can experiment with some carbon-fiber composites to create stiffer prints the nozzle screws into the hot end the hot end is made hot by this ceramic heater cartridge and a thermistor measures the temperature of the hot end and provides regulatory feedback to the microcontroller to make sure that the hot end stays within a set temperature range if the hot end is below the melting temperature of the filament then it can't be extruded on the opposite end of the spectrum if the hot end is too hot the molten polymer will either burn or have too low of a viscosity to be properly deposited onto the bill platform the upper portion of the extruder that starts with these aluminum fins is known as the cold end I defined the cold end to be from the fins to the top of the extrusion drive the extrusion drive is what pinches the filament and forces it through the hot end intuitively the filament has to be cold that the gears in the extrusion drive can grip the filament if the filament was soft and the gears wouldn't be able to gain traction this is similar to a cars wheels spinning in the mud the gears that have the splines cut into them and are responsible for grabbing the whole of the filament are known as hob gears I think technically the gears are my maker your m2 on your nose drive gears the drive gear doesn't have the contours the filament and just has the sharp teeth it's important to confine the molten filament to just the hot end the longer the distance of preheated filament the more likely the extruder is to jam for this reason the cold end is often actively cooled with a fan to prevent heat creep heat creep is the spread of heat from the hot end to the cold end which would result in more molten filament in some exterior designs such as the sine X which is smaller and I'm making gear m2 the extrusion drive sits on top of the cold end and moves along with it and other designs like the Ultimaker the extrude drive is fastened to the frame and is connected to the cold end by a long tube known as a Bowden tube there are pros and cons for both placements of the extrusion drive but I can boil it down to a pro and con for each with a boat and tube extrusion drive system the printhead can accelerate and D accelerate faster because the print carriage does not have the added weight of the motor this can significantly speed up print times the drawback for this setup is a distance between the extrusion drive and the hot end this longer distance results in the extrusion process being less responsive for people near to 3d printing the extruder not only has to eject filament on demand but it also has to attract filament and order to move two unconnected features or parts on the build platform this hysteresis or lag in the extrusion process is amplified when printing flexible filaments so it's best to avoid the Bowden setup when you expect to print flexible parts for the direct extrusion system the pros and cons are swapped you can't accelerate Indy accelerate as quickly because the carriage has the added mass of the stepper motor but the extrusion and retraction the filament is more responsive I tend to always employ direct extrusion as the maintenance is minimal further I tend to print out lower speeds anyways because part quality is always my highest priority we will finish up this section by talking about the extrusion stepper motor as I mentioned in the stepper motor section the amount of force required to extrude filament is unexpectedly high it is best to have a motor that weighs the least especially for the direct extrusion drive system recall from the stepper motor section that we can increase the torque output of a smaller NEMA motor through gearing the m2 uses nearly the same planetary gearbox setup as we previously covered the extrusion drive setup in the side X is a little different inside this black housing is a small gear this small gear sits on an onion pancake in Yuma 17 the gear then meshes with a larger gear and this larger gear turns a hobby gear this results in a three to one gear reduction or three times the torque this pancake NEMA 17 I should mentioned that the drawback of reduced speed is not as an important in the extrusion process where low motor speeds are used before we attach the extruder to the printer I want to talk about a different for the extruder a filament extruder I am definitely running the risk of confusing you because the extruder that we just built uses filament and it's extrusion process but hold on a second I can explain these spools of filament start off as plastic pellets these plastic pellets are extruded into a filament that will be fed into these annexes hot end I recently had the opportunity to build and play with the filament extruder and I wanted to show it off and explain why someone like myself would want to extrude their own filament the operating principle of a filament extruder is quite simple a motor turns a screw which feeds the pellet into a hot end with a nozzle that has a 1.75 millimeter orifice the plastic exits the nozzle through this hole where it is cooled by a fan this process is very similar to what we just discussed with the printer extruder but this is occurring at a larger scale it's very important that the filament has a constant 1.75 millimeter diameter as it exits the extruder any deviation will result in the 3d printer getting clogged if the diameter is too large or under extruding if the diameter is too small if you've ever purchased filament before and you may have noticed that filament not only comes in a 1.75 millimeter diameter but also a 3 millimeter diameter 3d printer extruders are not compatible with both diameters the one we just assembled accepts a 1.75 millimeter filament it's important to match your filament diameter to your printers extruder I always recommend a 1.75 millimeter filament purely because this is more common filament is very cheap so why would someone want to spend their time extruding their own filament in my opinion the most appealing aspect of owning a filament extruder is the ability to make the spoke filaments that sounded fancy didn't it but seriously the types of filament that can be made are endless I can create custom colors by adding different amounts of colorants or I can throw in some metal or ceramic powder to achieve some really cool effects the other benefit of owning a filament extruder is being able to turn failed 3d prints back into filament I just built this exterior last night so I've not had much time to experiment with it but let me know if a standalone video on filament extrusion is of interest to you starting for going off on a tangent there let's get back on topic now it's time to attach the extruders and drivers to the most DIY and inexpensive commercial 3d printers including Scitex these plastic components to hold onto the cold end of the extruder in my opinion this is not the safest practice because most plastics especially those that can be 3d printed have a low glass transition temperature this is the temperature at which the plastic starts to go from a hard material to a soft and rubbery one basically if the cold end fan ever stopped working there's a chance that the cold end could reach a high enough temperature that the plastic holding the extruder could flex worst case scenario the extruder slips out of its holder and lands on something flammable to be safe you should choose a plastic with the highest glass transition temperature as possible or avoid designs that use this setup there are two other things we need to discuss the part cooling fan and why the extrusion drive sits on a separate rail from the extruder let's start with the part cooling fan to put it simply some plastics print better if they are cooled quickly after being deposited by the nozzle one way to increase the cooling rate is to blow air over the layers that are being printed with an optional fan known as a part cooling fan zayed X has two part cooling fans one for each extruder and these fans are controlled by the printer software and can be switched on and off based on the plastic it's definitely not a bad idea to add a part cooling fan to your build next let's talk about why the extrusion drive for each extruder rides on a separate rail the speed at which a stepper motor can accelerate the extruder carriage is based on how much that carriageways and how much torque the stepper motor possesses because the extrusion drive is connected to the extruder via a boat into there's a small amount of movement the extruder can do without having to pull along the extrusion drive carriage because of the Flex and the bone do several motors have access to their maximum amount of torque after they're already moving so in theory it's Defra motor should have an easier time accelerating the extruder and then accelerating the extrusion drive but this could be negligible either way it makes the printer look cool and it works well in my experience [Music] with the two extruders installed this guy is starting to look like a 3d printer in the next section we're gonna go over the bill platform as the filament is pushed through the nozzle by the extrusion drive it needs a place to be deposited enter the build platform which is also known as the printbed the maximum part size that can be printed will be limited by the size of this platform however it is possible to install a build platform that is too large because the range of the extruder is going to be dependent on the length of its linear axis that it sits on now sonic says bill platform is undeniably small and this was perhaps the only reason that I was considering building a different printer for this video but this offers us a great opportunity to talk about what the optimal print bed size is when people first start 3d printing the initial instinct is to print larger and larger parts however fused filament 3d printers are limited by how quickly they can deposit material onto the bill platform the extruder is the main limiting factor some extruders like the e3d volcano or able to pump out massive amounts of plastic which allows large prints to be completed quickly the trade-off for these fast prints is resolution the volcano extruder is not capable of the small details that design X's v6 extruder is therefore the optimal size of the print bed should be decided in the design phase based off the dimensions of the parts you expect to print this decision will also influence the extruder choice for the v6 and many other extruders I find a printable area ranging from 200 millimeters by 200 millimetres to 300 millimeters by 300 millimeters to hit the sweet spot for allowing sufficiently large parts to be printed within a reasonable amount of time as I alluded to during the frame build the reason that I built sine x small bed and all is because I wanted a full feature 3d printer that was small enough to be transported to the 3d printing classes that I teach or local Maker Faires anyways let's get back on topic this section is called heated bed so where does the heat come in let's take a closer look at how the filament cools after exiting the extruder as the molten filament is deposited on the bill platform the edges of the print will cool faster in the center of the part this uneven cooling causes uneven contractions in the part which manifests in the corners lifting off the bed platform this is called warping and is not only undesirable aesthetically but also is unwanted because it can affect the dimensions of the 3d printed part to combat warping most 3d printers have a heated bed platform to maintain a constant temperature throughout the part as it cools heating the bill platform to 60 degrees Celsius will prevent warping when printing many different plastics while technically a heated bed is not required I would not build a printer without one because they are relatively inexpensive and the benefits far outweigh the cost I am currently soldering wires to the heated bed in order to supply a power I am also using thermal glue to adhere a thermistor to the bottom of the build so that the printer can monitor the bed's temperature you can purchase heated beds that come fully wired so don't worry owning a soldering iron is not a requirement for building a 3d printer although it is very useful the heated plate sits on a 3d printed part this part is made out of peak which has a high glass transition temperature and superb thermal resistance now you can't print directly on the heated bed which is usually a PCB heater a flat plate is put on top of the heater I always use a glass plate so wills INEX I think cover this glass plate with hairspray captain's tape or a combination of the two to help the first layer of filament adhere to the print bed rarely do I have adhesion issues with this setup however there are many other ways to successfully prep the build surface to allow for proper part adhesion but I don't have that much experience with them obviously you don't want the glass rattling around while you're printing so I'm going to show you how I make sure it stays put as you may know 3d printers are not so good at producing threaded holes but with an old soldering iron I can sync these threaded inserts into 3d printed parts which then act as a tap toll I can then easily attach other parts like these small pieces that will push up against the side of the glass plate holding it in place well that wraps up the printbed section next up we're going to talk about how the printer uses limit switches to determine a location of the extruder in relationship to the build platform the 3d printer needs a reference location known as a home to base all of its subsequent movements on to define a home location it's important to start visualizing the linear rails of this 3d printer as axes of a 3d graph with each axis having a positive direction ending in a maximum in a negative direction ending in a minimum for simplicity let's say this home location is at the minima of the x y&z axis or 0 0 0 when the power is turned on how does the printer find these minima this process is known as homing and can be accomplished by placing a sensor on each axis which are triggered when the carriage reaches the minimum these sensors are known as limit switches or in stops limit switches are characterized by how they are triggered zayed x uses mechanical limit switches which are triggered when bumped there are three other types of limit switches that we are going to discuss optical magnetic and resistive the mechanical limit switch is the most commonly used because of its simplicity and low cost it is fundamentally just a push-button with a special metal spring arm when pressed the switch will either open or close a circuit depending on how it's wired when placed at the minimum on the axis the carriage will bump into the limits which the microcontroller will sense a change in the state of the switch and will stop stepping the motor optical limit switches consist of an LED and a photo transistor with a light path between the LED and photo transistor is blocked the base current of the photo transistor decreases most optical switches translate these changes in photo transistor currents to a digital high or low signal based on if an obstruction is present making this limit switch type compatible with many 3d printer motherboards however unlike the mechanical switch the optical switch requires an extra wire that supplies power for the LED with optical limit switches the detection of the carriage is a contactless process you don't have to worry about parts fatiguing or wearing out over time like the spring arm of the mechanical switch magnetic limit switches operate on either the principle of electromagnetic induction or the Hall effect I'm going to demo a Hall effect switch but it's a good idea to read up on both sensor types if you choose one of the other for your limit switches similar to the optical limit switch all based switches are contactless but instead of detecting changes in light they measure changes in magnetic fields this is why there is a magnet attached to the carriage in the demo as the carriage moves the magnet closer to the minimum and hence the hall sensor there will be a distance at which an output signal is triggered this is about four millimeters in our example similar to the optical sensor the hall sensor needs an extra wire but in this case it's for a reference voltage which is required for the switching effect unlike an optical sensor the hall sensor is not affected by ambient light the final type of limit switches that we're going to discuss is resistive force sensitive resistors as their name implies change resistance when experiencing force here I'm compressing the sensor it's changed and resistance is detected by a small controller right here that relays a logic level signal to the main printer motherboard you can see that when I press on the sensor the LED on the board turns red similar to the mechanical limit switch the carriage has to touch the force sensitive resistor for it to be detected very rarely is this type of limit switch used to home carriages but it is used for probing the z-axis we will discuss the difference between probing and homing the z-axis in a second of the first three sensor types mechanical optical and magnetic which types would you choose to home each carriage to the axis minima objectively the magnetic Hall effect limit switch is probably the best choice it is highly precise and resistant to noise however these benefits come out at slight cost increase but across the board most limit switches are relatively inexpensive personally I always out for mechanical in stops they're low-profile simple and natively compatible with every 3d printer motherboard let's wire up some of the mechanical limit switches for side X each limit switch has three terminals they're either labeled c4 common n c4 normally closed or no.4 Leoben of the two wires needed one is dedicated to the common terminal to supply power to the switch base from whether or not the micro switch is pressed will determine which terminal the Commons connected to can you guess which terminal this would be if the switch is unpressed we can check with the multimeter again using continuity mode connecting one lead to the common pin we can probe the other two pins we see that unpressed the common line is connected to the normally closed if we press the switch the multimeter no longer beeps so the common no longer has a connection to the normally closed terminal the printer motherboard will sense this open circuit to determine that the carriage has triggered the limit switch so when the switch is pressed by process of elimination the common line must be connected to the normally open I always water my limits which is normally closed configuration so that the motherboard senses a disruption in the circuit this way if a wire becomes disconnected from the limit switch the motherboard will stop the carriage while this would not be true for a limit switch wired and a normally open configuration [Music] if you noticed sign X does not have a limit switch for the z axis instead this printer has a force sensitive z probe which I'm now going to elaborate on the most important distance in 3d printing is the distance between the extruder nozzle and the print bed at the start of the print if this distance is too great then the molten filament will not adhere to the print bed resulting in a failed print if this distance is too small and the pressure and the nozzle will build up because there's not enough clearance for the filament to be extruded which could also Jam the extruder resulting in a failed print in the same way that we found the minima of the axes with limit switches we can find the height of the print bed by triggering a force sensitive resistor that is either underneath the build plate or above the bill plate at a precisely known distance the extruder is then brought down to touch you of the build plate or the force sensitive resistor directly this process is called probing and the for sensitive resistor would be called the Z probe there are different probe types just like there are different limit switches a Z probe is not absolutely necessary but it can be used in addition to or in place of a Z limit switch it's time to discuss the puppetmaster for all these components the printer motherboard or as the cool kids call it the mobo all the electrical components will be connected to the printer motherboard which houses the microcontroller it's the microcontrollers job to enact the code from the 3d printer software to ultimately produce a 3d printed object this job includes not only barking orders like telling the stepper drivers when and in what direction to move the motors but also requires the microcontroller to listen and respond to various inputs like the extruder temperature or the state of the limit switches it's the motherboards responsibility to provide the physical connections for these electrical components the number of stepper motors heaters sensors and buttons that the motherboard can support is often a deciding factor when choosing a motherboard for example ZX has seven stepper motors all of which have to be driven independently very few motherboards have seven or more separate drivers let's walk through some of the motherboards that I have here to continue our talk on motherboard connectivity please keep in mind that this is a very small sample size all the different boards that do exist first off we have ramps now ramps is really just an Arduino mega shield which allows an Arduino mega to control 3d printer components that operate at greater than 5 volts this board allows for up to 5 stepper motors to be attached and controlled independently the 5 summer motors are connected here here here here and here wire supplying current to the heating element are attached here this includes the heated bed and up to 2 extruders and limit switches as we have just discussed are attached to these banks of pens and the thermistors which regulate the temperature of the extruders and heated bed are attached to these pins is already turning into a little bit of a mess but don't worry we're gonna talk about wiring and more detail in its own dedicated section for $30 or less you can have the Arduino mega ramp shield as well as 5 stepper drivers however its low cost means that it's missing some key features such as a park cooling fan header and LCD header in any kind of fail-safes for improper wiring next up we have the MKS board which is really just a ramps in Arduino mega incorporated on a single board wherever this motherboard does have a dedicated part cooling fan terminal and LCD pin header this board comes in at the same price as the ramps plus Arduino mega so having a little more connectivity at the same price means the MKS board is the way to go on a budget the third motherboard is called a Rambo and while it looks similar to the MKS board is roughly five times the price what is accounting for this price difference well quality and reliability while Rambo still uses the same Arduino processor as the previous two boards the board design and components are superior to that of the previous two boards we discussed a couple examples of this superiority are the use of real fuses for each voltage rail and the ability to tune the motor current digitally a couple of years ago Rambo was the go-to motherboard for high-end 3d printers but today the high end motherboard market is packed with competitors our fourth and final board is one competitor before we talked about the last board I want to talk about motherboard firmware simply put the firmware is the code that bridges the software that generates 3d printer files and the hardware that makes these files our reality when you purchase a motherboard you're buying into one of the ten plus firmwares that exist while all firmwares readily support the most common types of fused filament 3d printer designs there are subtle differences between firmwares which can make more complicated 3d printers like design x difficult or impossible to set up keep in mind that Z X is an extreme example with its two independent z-axis and x axis printer compatibility can be easily checked on the firmware documentation when building your own 3d printer you will have to edit the firmware with your printer specific values for example in the transmission section I showed you how to determine the distance the carriage moves per rotation of the stepper motor this value and others will be inputted into the firmware some firmware as are easier to edit than others the first three boards share the same firmware known as Marlin Marlin is feature-rich and its widespread use makes it easy to get help on forums during setup I have used Marlin for years my 3d food printer and 3d printed 3d printer both used ramps running Marlin the only negative side of marlin is that it has so many features that it can be difficult for newcomers to navigate now the fourth motherboard known as to do it to Wi-Fi uses a different type of firmware known as a RepRap firmware which is perhaps when the best parts about the duet we will come back to that let's do a quick overview of this board first impressions the duet looks a lot more powerful than three previous boards partially because of its large 32-bit processor and it's beefy stepper drivers look at the size of the duet stepper drivers compared to the stepper drivers of the rambo let's talk a little bit more about the duets microcontroller compared to the 8-bit microcontrollers of the previous three boards the duet 32-bit processor can perform quicker calculations allowing for better stepper motor performance at high speeds plus it can control up to ten stepper motors if you have the expansion board this is the main board this is the expansion board they're joined together by a ribbon cable the Scitex uses the duet plus expansion board because it needs for drivers there are a lot of other really cool features to do it but the final one I want to touch on in this section is the web interface made possible by the RepRap firmware while other 3d printer web interfaces exist the duets is the cleanest and the only one where the firmware it can be accessed via the web interface being able to edit printer parameter such as stepper motor speeds and extruder offsets on the fly is a godsend for people building and calibrating 3d printers of course there's always a cost for greatness and the duet plus the expansion card is one of the most expensive motherboards for 3d printing it's impossible for me to recommend one motherboard because every printer and user is going to have different needs for a simple single extruder cartesian 3d printer a cheap MKS board would work just fine but maybe you can justify purchasing an expensive do at Wi-Fi after reviewing all the features in the next section we're going to discuss stepper drivers when the stepper drivers are soldered in the motherboard like in the case the duet or in the case of Rambow they too can be a deciding factor in which motherboard you choose the stepper driver converts digital signal from the microcontroller in a stepper motor rotation by sending variable amounts of current to the stator phases let's walk through this entire sequence of events that end in the stepper motor moving to emphasize the importance of the stepper driver first a program known as the slicer converts a digital file to be 3d printed into three-dimensional coordinates known as g code it should be noted that this g code also contains other important information for the printer such as extruder temperatures and fan speeds the microcontroller on the 3d printer motherboard represented here by the arduino Reeves as G code in its interpretation of the code is based off its firmware when the microcontroller reads a G code coordinate it checks location of the extruder and determines which stepper motors need to be moved in order to get the extruder to desired location the microcontroller also relays the direction of the driver needs to move the motor either clockwise or counter clockwise from these signal inputs the stepper driver changes the magnetic fields of the phases to rotate the motor shaft as an example I've gone ahead and wired up a stepper driver to an R we know which will send the step in Direction signals it looks a little complicated but the most important wires are those connected to the step in Direction inputs on this step or driver which are the yellow and orange wires respectively the other wires are two separate power connections 24 volts for the stepper motor and five volts for the stepper driver logic don't worry you won't ever have to wire up a stepper driver like I'm doing to the microcontroller if you buy any mainstream motherboard however you will have to connect the stepper motor to the driver phase bends in the motherboard section I briefly showed you guys where those phase pins were located at on the ramps board there are two phases and two wires per phase hence four pins here the red and blue wires power one phase and the green and black wires power the other the motor will work as long as the wires that are on the same phase are plugged in next to each other even with this requirement there are still more than a couple of configurations that the phase wires can be connected like this or this let's do some experimentation to see what happens for each case now I could've done this experiment on the ramps board that I was just holding but I would have to plug in a couple more 3d printer components to make sure that the board didn't throw an error so it's easier for me to showcase the differences in stepper motor wiring with this Arduino setup that I have here again the red and blue wires would share the same phase are plugged in next to each other and the green and black wires that share the same phase or plugged in next to each other I created a small Arduino program to tell the stepper driver to rotate the shaft one full rotation in this configuration the stepper motor shaft rotated counterclockwise let's swap the two sets of phase wires and see if that has any effect on the direction of movement interesting we got clockwise rotation there let's swap the two wires within a single phase we're now back to that counterclockwise rotation let's swap the wires in the other phase that caused the shaft to turn clockwise so what have we learned here well if the two wires that belong in the same phase are next to each other then all is good the stepper motor is going to work we also learned that the direction the motor rotates is dependent on the order of the phases and the order of the wires that supply the power to the phases every time I swap the wire I was reversing the current in one of the two phases the stepper driver contains electrical components that allow it to change the direction of current flowing through the phases which is how it changes the direction the motor rotates after receiving a new signal from the direction pen when you first get your 3d printer up and running if the carriage is moving in the wrong direction you can either swap two of the wires as I have done or a small adjustment in the firmware it can be made now the stepper driver needs to be sized correctly to the motor that it is going to control this larger stepper driver can power either the smaller NEMA 17 or the large NEMA 23 however this small stepper driver cannot offer up enough current for this large NEMA 23 to Oprah it properly without the driver burning up fortunately because one stack NEMA 17 stepper motors are almost universally used for 3d printers most motherboard manufacturers pre installed drivers capable of controlling such stepper motors this way the end-user doesn't have to worry about selecting an appropriate stepper driver however issues arise when these 3d printer motherboards are adapted for larger applications like CNC machining which uses larger stepper motors the stepper driver from our examples has been the a four nine eight eight which is an extremely common and cheap driver all of the previously discussed motherboards except for the duet use this driver the do it on the other hand uses trained ammok TMC to six60 drivers these drivers are magical and I need to be careful not to geek out too much about them on camera one awesome feature of this driver is its ability to detect when the motor stalls on zayed X I can block the movement of its y-axis and a warning will pop up in the web interface that obstacle has been detected this stall detection will prevent the carriage from getting abused if say I left a screw driver on the rail the other awesome feature that I want to talk about is how quiet and smooth the try Namek drivers step the motor compared to the a four nine eight eight drivers in addition to my a four 988 example I've also wired a try Namek stepper driver to a microcontroller and stepper motor we should be able to tell the difference just by listening here is the a four nine eight eight in action and here is the try Namek driver the noise profile of the tri Namek controlled separate motor is not only quieter but also smoother in our next section on microstepping we will first define this term and then talk about how the tri Namek stepper drivers use microstepping interpolation to achieve the smooth and seemingly vibration free movements the final step or motor topic is upon us its microstepping let's first review the step size of a stepper motor a complete 360 degree rotation of the stepper motor shaft is comprised of discrete steps the most common step size is 1.8 degrees as I briefly showed in the stepper motor section this 1 point 8 degrees is a product there being 50 teeth on this stepper motors rotor a stepper motor with 100 rotor teeth would have half the step size however there are ways to get smaller step size without increasing the rotor teeth count maybe you are wondering why a smaller step size would be advantageous for 3d printing higher resolution is a fairly obvious benefit from decreasing the step size but let's talk about why a 1.8 degree step size is too large to produce quality 3d printed parts the timing belt ons on axis Y axis is driven by a 22 coley recall from the transmission section that the 22 the would move the belt 40 millimeters per rotation the smallest distance that the Y carriage can be moved with a 1.8 degree stepper motor operating at its full step size is going to be 40 divided by 200 which is 0.2 millimeters or 200 microns while this sounds like a small distance it is not sufficient to print some geometries for example a Cartesian 3d printer like Z X has to approximate curves with small stairs if these stairs are sufficiently small and the curve will look and feel smooth but at a resolution of 200 microns you would be able to feel and see the stairs it's difficult for me to say at exactly what resolution these stairs would appear smooth but generally 50 microns or less is best the other benefit of decreasing the step size is less obvious and does not improve print quality but it is important nonetheless when the several motor shaft takes the step the rotor does not lurch forward one step and then immediately stop the Rhoda will overshoot the step size before being drawn back in the opposite direction this is known as overshoot or ringing and will occur multiple times before the rotor comes to arrest these oscillations generate noise and vibrations especially when the severed motor is operating at large step sizes and low speeds therefore stepper motors that take smaller steps produce less noise let's compare the noise level of a stepper motor operating at a 1.8 degree or full step size in another operating at 0.1 one to five degrees or a micro step size the stepper motor that is microstepping has 3200 steps per rotation compared to the first step or 200 steps I have both motors program to rotate at the same speed listen closely to the difference in loudness between the motors clearly the first stepper motor is louder you have to keep in mind that during printing is common to have three stepper motors moving at one time the x axis stepper the y axis stepper and the extrusion drive stepper so really you have to multiply this noise level by three the full step and microstepping motors are identical the difference is that the stepper driver for the microstepping motor is set to a 1/16 microstepping mode this mode takes one full step and divides it up into 16 micro steps hence the 3200 steps comes from 16 times 200 full steps instead of switching the phases on and off the driver gradually transfers current between phases which allows for these smaller step sizes even smaller micro stepping increments to exist such as dividing one full step into 64 or even 128 micro steps but there are diminishing returns for using smaller and smaller micro steps because while resolution increases with decreasing step size the motors accuracy remains unchanged there are also other issues when employing really small micro steps such as the lack of incremental torque between micro steps and the need for the microcontroller to have higher processing power to generate faster step pulses micro stepping really is a fascinating topic and I highly recommend clicking on some of the links that I have provided the last couple of things I want to talk about this section are how to enable micro stepping what micro stepping means for our steps per millimeter conversion and the micro stepping interpolation of the Tri Namek stepper driver the way in which micro stepping is enabled will depend on the drivers and the motherboard first and most importantly make sure your motherboard and separate drivers support micro stepping the most common method to enable micro stepping is through rearranging these jumpers the motherboards documentation will show which jumpers need to be connected for 1/16 micro stepping mode which is the micro step size that I recommend some other boards allow for micro stepping increments to be digitally set via the firmware when we enable micro stepping how does affect our steps per millimeter well this does per millimeter will be scaled with a number of micro steps per full step for the 22-foot it was 200 steps per 40 millimeters or 5 full steps per millimeter if 1/16 micro stepping mode is enabled we have electronically segmented one step into 16 so we'll now take 5 times 6 or 80 steps for the stepper motor shaft to move the bill 1 millimeter this section became longer than I had intended but hey it was time well spent because this is an important topic I'm gonna quickly finish by talking about microstepping interpolation that the Tri Namek stepper driver used in the stepper driver section to operate so quietly compared to the a4 988 which does not have this feature both stepper drivers were configured in 1/16 microstepping mode and received 3200 step pulses per rotation for the micro controller but the Tri Namek stepper driver broke down the 1/16 steps into 1 256 steps now this may be a little bit confusing because I had previously said that there were little benefits to these small micro steps however the Tri Namek stepper driver is performing this interpolation not for the purpose of increasing resolution but to allow for smoother operation of the stepper motor plus these calculations are done on board the stepper driver so this micro stepping interpolation is not any more intensive than 1/16 micro stepping for the micro controller I hope I didn't confuse you too much at the end this section it's now time to talk about power supplies 3d printers don't run off wishful thinking the motherboard cannot be connected directly to an AC outlet for power it requires a low DC voltage either 12 volts or 24 volts depending on the motherboard and 3d printer components a regulated DC power supply unit will step down and rectify the AC voltage from the wall to supply a constant DC current most DC power supplies are metal boxes with a row of screw terminals three of the screw terminals taken the AC power lines while the other terminals are the positive and negative outputs for a single DC voltage using a 24 volt power supply is generally recommended over a 12 volt power supply 24 volts will increase the performance of the stepper motors at high speeds and lighter wires can be used as the heated bed will require less current at higher voltages whether you choose a 12 or 24 volt power supply it is necessary to make sure that your extruder and heated bed are compatible extruders are either sold as a 12 volt or 24 volt Edition the heated bed can usually accept both voltages but where the wires are connected will depend on the voltage supplied after deciding on a voltage the last consideration for the power supply is the output current the output current times the voltage will equal the power supplies wattage the higher the wattage the more expensive and larger the power supply will be the wattage of your power supply will depend on how your printer is configured stepper motors extruders fans and LEDs will all draw power the wattage of each component can be found on the manufacturers datasheet but a general rule of thumb is to a lot 100 watts for all electrical components in a single extruder setup except for the heated bed the heated bed is a power-hungry component design X's little heated bed requires 100 watts on its own to determine the wattage needed for Z X I treated it as two single extruder printers which would be 200 watts and I added the 100 watts from the print bed so my 350 watt power supply is perfect the last thing I'll say about power supplies is to buy one from a reputable company poorly manufactured power supplies could fry your printer motherboard I find the manufacturer mean well to supply quality power supplies on a budget the power supply will be mounted underneath the y-axis it will be mounted with of course another 3d printed part if you remember from when we were building the frame I attached these feet to give the power supply more clearance because the fans on the bottom now might also be a good time to mention that I don't have the LCD on this second printer the duet web interface was too good I never really used the LCD on the first printer that wraps up the power supply section we're finally going to deal with this mess of wires before we can connect the electrical components to the printer motherboard we need to organize all these wires some people find wire management peaceful I find it frustrating nevertheless it's very important that the wires are properly tucked away to prevent them from getting caught in any of the moving components when you tuck the wires away there must be enough slack in the wires such that the carriage can move to the farthest part of the AXI without being held back one common way to manage the extruder wires is to wrap them together and sleeving and suspend them through an anchor point that is higher than the extruder I chose to use drag chains to manage z-axis wires they may be overkill but they do add at the industrial look and they also work well the wires that come with the stepper motors are not long enough to reach the motherboard after being snaked for the drag chains this is especially true for the extrusion drive and x-axis steppers now you could always start around longer wires but I've taken a starless approach by using these screw terminals they're definitely more expensive than soldering but they're a good option for people who don't own a soldering iron [Music] [Applause] [Music] I'm now going to wire the power supply to the motherboard which divides the power among all the electrical components in the power supply section we calculated that ZX is going to need about 300 watts of power it is very important that the wires from the power supply are capable of safely carrying this much power to the motherboard if the diameter of the wires is too small for the amount of power that is carrying and the wires could burn out so choosing the wrong wire diameter which is known as the wire gauge in the business is a serious problem which unfortunately happens all too often proper planning can guarantee that you select the correct wires let's walk through how I chose the wires between xanaxes power supply and the motherboard again we estimated the power draw of the Praire to be 300 watts at 24 volts the wires need to supply 12.5 amps of current to reach this power rating the current is what dictates the gauge of the wire you can Google maximum current load for each wire gauge but these charts can vary based on the metal used in the wire and at the wire is solid or stranded core I find it easier to only buy wire where the maximum current load is listed in the product description the wires I am using for Xanax are capable of carrying 8 amps of current yes this is lower than 12.5 amps but I'm using 2 pairs of these wires because the expansion board has its own power input I should also mention that these wires have insulation that is rated for relatively high temperature applications which is a good specification for any wires used when building a 3d printer this is kind of an obvious statement but wire management is made easier when the wires are the correct length however when cutting wires down the size you will cut off the end connector if there is one present to recreate a connector a crimping tool is used to connect a conductive piece of metal that has then slid into a plastic housing which can accept the male pins of the motherboard it can take a little practice to perfect your crimping technique this is a very useful skill for any kind of electronics work [Music] [Applause] [Music] most people are really intimidated by the process of actually wiring the electronics to the motherboard I think the stems from the fear of getting positive and negative wires mixed up and accidentally frying the motherboard or the component that was just plugged in fortunately this concern is mitigated by the fact that most 3d printer electronics are blind to the polarity of a circuit let me explain through an example both the heating element and temperature sensitive resistor of the extruder can be plugged in to their corresponding pins in either of the two possible directions and will still operate perfectly fine it is however critical to get the polarity correct for the positive and negative wires coming from the power supply you should always reference your motherboards wiring guide in the physical marks on the motherboard to determine which terminal on the motherboard is for the positive power input and which terminal is for the negative power input but let's walk through the other components determine if they are sensitive to polarity the heated bed is also just a fancy resistor so its wires can be connected either way to the heated bed terminals the limit switch is now straightforward the polarity does not matter but some of the higher-end motherboards have an extra pin to supply the power needed for an optical or magnetic limit switch but for a mechanical limit switch you don't need this third pin so you want to make sure that you don't connect the switch to it the part cooling and cold end fans are sensitive to polarity and that they will only work if their red wire is connected to the positive pin and the black connected to the negative pin if this was reversed it's not the end of the world the fan would not turn on until the wiring is corrected but nothing would be damaged while we were talking about fans I should also mention that a motherboard cooling fan or two is highly recommended as the stepper drivers can run quite hot the last common 3d printer component would be the stepper motors and we've already talked at length about all the possible wiring configurations none of which would hurt the stepper motor or the motherboard to find the exact location for to plug in each component you'll have to consult the wiring guide specific to your motherboard well that wraps up the wiring section the next big question is how does the motherboard know what type of 3d printer it's a part of we will solve this at any crisis in the next section on firmware let's plug this printer in it's a good sign that it turns on however we are still a little ways from printing our first part currently there's a major disconnect between the software and the hardware is that X is duet motherboard can be used to control a bunch of different types of CNC machines how do we describe all the hardware components to the motherboard such that it knows it's controlling a 3d printer and not say a laser cutter and what ZX specific features do you think are important to describe to the motherboard may be started listing features like the dual extruders the size of the printbed the fact that the x and y axes use a belt-driven transmission while the z axes use a lead screw to driven transmission this list is a great start but there are many other parameters that the motherboard needs to know to understand the z-axis configuration all of these parameters are stored either directly within the firmware or in a separate file known as a configuration file that configuration file is then referenced by the firmware recall from the motherboard section that firmware is the code that bridges the 3d printer hardware and the software that contains the 3d models to be printed the firmware cannot do its job properly if the configuration file is not set up correctly because there are more than 10 different firmwares in many different 3d printer setups it's not possible for me to give you the exact values for your configuration file or even where to input these values because each firmware is laid out differently however I will introduce a tool that will make setting up the configuration file easier and then go over some of the important parameters that are found on all firmwares editing firmware and our configuration file is daunting for many people without a coding background I fell into this category when I was building my first 3d printer fortunately most firmwares today have at least a third if not first party configuration tool that walks you through all the parameters that need to be assigned values we are going to quickly flip through the configuration tool for the duets RepRap firmware please keep in mind that the configuration setup tools for other firmwares may look a little different and use slightly different names for the same parameters on the first page of the configuration tool I should point out that if you're following a published 3d printer build then most likely the configuration file is available for you to download so you wouldn't have to do any of these next steps but if you make any changes to the original design of the printer such as making it larger you will have to manually input these new values into the configurator so keep watching we have to set up a custom configuration for his I'd X and for simplicity I'm going to configures out X as a fixed dual extruder printer it's actually not possible to configure an independent dual extruder in this web program at the time of recording that is only possible through direct editing of the configuration file don't worry we'll handle that later the next page is where you set the printers geometry and the lengths of the axes that X is linear rails or septa mimic a Cartesian coordinate system which is selected by default the x y&z Maxima are the maximum distances each carriage can move on its rail which may or may not be the entire length of the rail the homing preferences are not super important and can be tweaked later at any point you can hover your mouse over a field to get more information on that parameter in the motor tab we can configure all the stepper motors and drivers first up we can set the microstepping level 1/16 microstepping denoted here by x 16 is universally selected for 3d printing because the duet uses the Tri Namek stepper drivers we can also turn on the micro stepping interpolation which is accomplished through selecting the x 16 with on in parentheses next we have the steps per millimeter I've gone through this calculation a couple of times in previous sections but keep in mind that this value is not the full steps per millimeter for the number of micro steps per millimeter the next four parameters max speed change max speed acceleration and motor current are all going to depend on the stepper motor chosen and the weight of each carriage in the extruder section we talked about the different extrusion drive setups direct and Bowden the motors that are responsible for moving the extruder around in the direct setup will have to move more mass in a lower acceleration and max speed change will have to be used compared to a Bowden setup there are calculations that can be performed to estimate the optimal values for these prayer and I will link to these calculations on my website but most people try and dial in these parameters based on their print quality if you're having issues with your initial prints try lowering the Mac speed change Mac speed and acceleration it's very common to run the motors at fifty to eighty percent of the rated current at 100% current or higher the motors will run very hot which is not ideal for printers like zai Dex where some of the stepper motors are being held to the frame by 3d printed parts if you're using a more budget-friendly motherboard like the ramps or MKS you'll most likely have to adjust the motor current manually by turning the screw that is directly on the stepper driver this screw is known as a dashpot and for the a four nine and eight separate drivers turning the dashpot clockwise will increase the motor current while counter clockwise reduces it in the last column we will select where each stepper motor is plugged in the xanaxs motherboard has ten possible stepper drivers so during wiring it's important to keep track of which stepper motor is plugged into which stepper driver now on to the extrusion drives we need to add an extra extruder because it's not access to extrusion drives these stepper motors are configured similarly to the AXI stepper drivers but the steps per millimeter will depend on the gearing of the stepper motor when you're using an underpowered stepper motor for the extrusion drive like I am you will want to crank the motor current up as high as possible to squeeze a little extra power out of the motors but I would caution you on doing that because if the stepper motor becomes too hot it could pass this heat onto the filament if the filament heats up and becomes soft it can't be accurately extruded I don't think I mentioned this during the build but this is the reason I placed these aluminum heat sinks on the back of the extrusion drive steppers it helped keep them running as cool as possible we won't worry about the motor current reduction this is a nice feature but it's uncommon on most motherboards next up we have the limit switch or in stop parameters my x and y axes the limit switches are mechanical and wired in a normally closed configuration as discussed in the limit switch section they are located at the minima of the rails the z-axis uses a Z pro instead of a limit switch and because the Z probe sits above the bed we have to enter its height in the trigger height field let's keep rolling to the heater section do have a heated bed and this is checked by default the control method is an algorithm that maintains the temperature of a heated component based on feedback from the thermistor without getting into too much detail PID or pit is a more accurate way to regulate the temperature of a heated component and is always the preferred method for heating extruders before heated beds with large thermal masses bang-bang control is adequate next we have to define the maximum temperature limits for the extruders and heated bed which is going to be based off specifications supplied by the manufacturers since the heated bed comes in contact with a lot of her components it's important to make sure that all these components are rated for the maximum temperature limit we have to add a second nozzle for the second extruder the pwm limits are fine at 100% this will allow the heating elements to draw maximum power if needed to reach their set temperatures finally the r-25 beta and C values are variables that describe what thermistor is being used to regulate the heater I don't think I ever fully explained how a thermistor works but basically it changes resistance proportionally to changes in temperature the r-25 value is the thermistors resistance at 25 degrees Celsius and the beta value is a constant that describes how the resistance changes with temperature to be honest I'm not sure what the purpose of the C value is but it can't be too important if it defaults to zero you saw me install a thermistor on the bottom of the heated bed but what you didn't see is I found that thermistor at the bottom of a bin and the only thing I knew about it was that it's r-25 value was 100 K I could calculate the beta and C values by sticking the thermistor in my oven and measuring its resistance at known temperatures but I have not gotten around to doing that yet the default values will be fine because precise control over the heated bed is not critical fortunately for the nozzles where precise control is important there's already default for the thermistors that come with a genuine III db6 extruder if you bought a v6 clone and the thermistor supplied could be different so double-check this before I go to the next tab I wanted to point out that yes I am flying through these configuration parameters when I was planning out this section I realized that I could probably make a 2-hour video out of just sending up a configuration file then I thought wait a second I named this video how to build a 3d printer not how to program I can save myself the effort and just skip this section entirely but if you watch this video from the beginning and you're probably very interested in building a 3d printer and this is the ultimate guide so I shouldn't leave you hanging my compromise between telling you everything about configuring the firmware and nothing is what you're watching now think of this section as mean demystifying the parameters that are required for the perimeter work properly and not a thorough explanation Google and your motherboards documentation are going to be your friends at this point in the build especially since your firmware will most likely be different from mine after saying that I'm going to hurry through these last couple of sections next we need to configure the fans that X has for fans need to be controlled during a print two of these fans are used to keep the cold ends of the two extruders from heating up both these fans would be under the thermostatic control of the extruder for example once the extruder hits 45 degrees Celsius the cold and fan should turn on to prevent heat creep the other two fans are for part cooling depending on the type of filament we may or may not want the cooling fans on for some reason the configurator doesn't let me add a fourth fan with the expansion board the duet can control up to nine fans I will add this fan to the configuration file manually later and most firmwares the extruders are called tools we need to assign each combination of extruder : fan and part cooling fan to a separate tool I would also like to point out that the first tool is tools zero and not to a-1 the next tab deals with the auto bed leveling settings because I access bed is so small I was able to level it manually but looking back this is a pretty useful feature that is absent from the video I highly recommend for you to look into this feature further especially if you're building a large format 3d printer in the second and last tab we have the network settings because it is a duet Wi-Fi after all you connect to the printer over Wi-Fi lastly we can append custom settings to the file but I find this easier to do in a text editor once we download the configuration file we'll click finish and then download the file opening the system folder we find a bunch of different text files we're going to open the config file but if you're curious the other files tell the printer what to do if a certain command is issued by the user for example maybe when you home the x-axis you want an LED to turn on you put the code to turn the LED on in the home ax G this organization is specific to the RepRap firmware opening the config file in a text editor we find a well-organized g-code file with all the parameters that we entered into the configuration tool on the Left we have G and M commands and on the right we have comments describing what each command does according to old CNC books the G stands for general and the M stands for miscellaneous which is not helpful at all and describing what these groups of commands do G commands are typically used for motion and make up 99% of the 3d printer file as ultimately sent to the printer I like to think that the M stands for machine specific commands this is why a configuration file that contains machine specific parameters is mostly made up of M commands g code is very easy to modify and i'm going to demonstrate how to add that fourth fan which happens to be the second extruders part cooling fan - the config file looking at the block of code that deals with fans it looks like the m106 command is for adding a fan even with The Associated comment it's not totally clear what the p.s.i and other parameters are doing the RepRap wiki's G code web page will give us a little information on these parameters as I'm scrolling past all these other commands I hope this helps you understand why it would be difficult for me to cover all the different commands and impossible for me to create a configuration file that would work for all 3d printers operating on any of the number of firmwares while most firmwares use the same G codes for common operations the m106 command is a great example with all firmwares using this to set up fans this is not the case for all commands let's continue with setting up our fan the peep parameter is the fan number which corresponds to a specific fan header on the duet motherboard we were setting up our fourth fan which confusingly it would be phantom 3 because the first fan is zero the S parameter refers to the fan speed for RepRap firmware the fan speed is on a scale from 0 to 1 the configuration file is executed on startup and we don't want the part cooling fan internal until a print starts so we will set the fan speed to 0 when the printer starts we can send a command to get fana turn on P and s are the only required parameters but we can add any of these extra parameters to fine tune other properties of the fan such as placing it under the thermostatic control of an extruder this is how the cold and fans for both the extruders are set up in the config file when the extruder becomes hot in our case higher than 45 degrees the cold and fan is switched on it's best practice to assign a value to as many parameters as possible because left undefined most these parameters assume a default value which may be different than what you would expect this is why I have added the AI parameter which typically disables fans instead to zero effectively I have disabled the disabling of the fan if for some strange reason this parameter defaulted to something else and prevented the fan from turning on it would have taken me a while to figure it out the default frequency for the PWM fan output or the F parameter is also 500 Hertz but I have explicitly typed this in and finally because the part cooling fan should not be under thermostatic control I made sure that it isn't by passing a negative 1 to the H parameter and with that the extra fan is all set up obviously this addition to the configuration file is trivial compared to some of the modifications that need to be made for a more exotic 3d printer like sine X and it's two independent extruders you can download my configuration file for zayed x at my website if you want to take a look at all the manual changes that had to be made from what was spit out of the configuration tool I know that I left a lot of stones unturned in this section but I hope I was able to demystify some of the software setup there's required in building a 3d printer in the next section on calibration we'll make sure that the parameters that we input into the firmware translates as expected to real-life 3d printer functions the moment of truth is here well this printer worked perfectly on the first print probably not out of all the steps in building this printer from sourcing the parts to the actual assembly calibrating the printer takes the longest if I was being really dramatic then I'd say that a printer is never truly calibrated as the optimal print settings will depend on the 3d model to be printed and the filament that is being used don't be discouraged if your initial prints fall short of your expectations in this section we'll first check of the configuration parameters we enter last section are correct and then we will discuss some of the print settings that can be tweaked to improve print quality I just uploaded the config file and now it's time to make sure that everything is operating as it should if you have any experience with 3d printing and you will know that a computer is required for generating and sending g code to the 3d printer while you can technically send g code through a terminal i prefer to use 3d printer specific software such as simplified 3d which is a paid program or a pronterface which is free these programs have user interfaces that generate g code based on mouse clicks which is way simpler and quicker to use xenix is duet Wi-Fi motherboard comes with its own web-based UI which is used to communicate with the motherboard and is what you will see me using after the computer recognizes the 3d printer the first thing you want to check is that all the carriages move everything seems good so far with Scitex but if a motor is stuttering then the usual culprit is the wiring if you're using screw terminals like I am make sure there is no loose connections and no electrical shorts once all the carriages move appropriately we can worry about the direction they are moving the direction in a sense is arbitrary however you want to make sure that the location of the limit switches match up with the direction when I was configuring scitex I had said that the limit switches are at the low end so I need to make sure that when the carriages move in the positive direction they get farther from the limit switches if this is not the case then you can change the direction of stepper motors move by editing the configuration file or changing the wiring of the stepper motors as we talked about in the stepper driver section next we need to test the limit switches in ends I oxygen each axes separately and make sure you can quickly turn off the printer in case the homing switch doesn't trigger it's never pleasant to watch your brand new creation run into itself I'm not gonna Holmes idec's by hitting these buttons on the interface so first off we have the x-axis we have the y-axis now the z-axis lifts up slightly just to make sure that the y-axis doesn't hit anything when it's moving then it puts it back next we have the z axis well hold on which at home the U axis first we haven't talked about this yet we're going to get more into the dual extrusion setup of Z X in the next section so we'll go ahead and home this axis it's known as the U axis then we have to home a z axis again it lifts up first it lifts up anytime it's about to move the y-axis and the slide the Z probe in here and we're good to go if a carriage fails to home there is usually a loose wire or there's a mismatch between the wiring of the limit switch and how the configuration file is set up if you have a Z probe like I did it's important to check that the trigger height is correct the trigger height is the offset that is applied after the Z probe is home clearly Wenzhou next is extruder touches the Z probe is not at Z equals to 0 after correcting for the thickness of the Z probe the nozzle of the extruder should be about the thickness of a business card away from the print bed this same distance goes if you're using a z-axis limit switch now we need to set up the extruder I had briefly mentioned in the last section that the exteriors temperature is controlled through a feedback algorithm known as pit or PID to be briefed this algorithm needs to be tuned to smooth out temperature oscillations I know this sounds complicated but it is an automatic process that only needs to be completed after installing a new extruder the auto tuning is accomplished with a simple g-code command you will see some temperature fluctuations in the extruder then after a couple of minutes the firmware will spit out values for the P I and D parameters you usually have to save them in the firmware through another g-code command after that the extruder should be all set up we will load some filament to check that the extrusion drive is working properly and to prepare for our first print I'm going to remove the guide tube so you can see everything that's going on first me to heat up the extruder it will take about a minute for the hot end to heat up the cooling fan has turned on which is really important if for some reason you're cold and fan doesn't turn on again you have to go back in the configuration file and make sure it's set to thermostatic control if you hear even more noise the power supply fan actually kicked on as well now that the hot end has come to temperature we can have the extrusion drive start to push the filament down into the extruder you can feel when the hob gears grip the filament and start to pull on it you can feel when the hob gears start to grab the filament and pull it down after that you can let go while we're waiting let me explain the purpose of a guide tube it prevents the filament from getting caught in any of these moving parts which would cause it to snap accurate extrusion of the filament is very important for print quality to make sure that the extrusion drive is pushing out the right amount of filament we will double check that when instructed to extrude 100 millimetres of filament that well 100 millimetres of filament is extruded I typically use a sharpie to mark the filament 100 millimetres above the cold end if all goes well and that black mark will be barely visible above the cold end after extrusion this method doesn't result in most accurate measurement but it should tell us if we were in the ballpark later on if the printer is under or over extruding we can make minor adjustments to the filament flow rate through a parameter known as an extrusion multiplier is onix's extrusion drive seems to be extruding appropriately if you find that your black mark is either inside of the extruder or way above it the most likely your extrusion drive steps per millimeter is incorrect where the filament is slipping at the hop gear most extrusion drives have some sort of tensioner that can be increased to prevent slipping it's time for exotics is first print what will it be can I get a drumroll it's gonna be a cube okay maybe a little anti-climatic but a cube can tell us a lot about the accuracy and alignment of a printer you can find a printable cube online or you can create one in a CAD program like fusion 360 just make sure you know the dimensions in my case the cube is 30 millimeters by 30 millimeters by 30 millimeters we need to convert the 3d file describing the cube in the g-code because that is what 3d printers understand this is accomplished through a software program known as a slicer my favorite slicer is simplified 3d because it is compatible with many different types of 3d printers before importing the cube into your slicer of choice it's important to make sure that this software understands your printer setup simplify 3d has a configuration assistant for setting up new printers that allows you to input custom parameters after selecting other ins onix's case I only have to change the name and build volume and check that 0x has a heated bed when we set up the second extruder in the next section we'll have to make a couple more changes but for a single extruder setup we're good to go next I will import the cube into simplify 3d and then pull up the settings for the print to keep it easy I'm going to keep the default settings for PLA which is the plastic you saw me load into the printer after that we click prepare to print and simplify 3d converts the cube into g-code simplified 3d can send the g-code directly to a 3d printer if it's connected by USB but design X is a wireless printer so I will save the g-code and then upload it to the web interface the print bed and extruder will heat up and then the print will start the first layers of the print are critical as I talked about in the heated bed section if there's an issue with these layers and it is most likely one of two problems via the nozzle is not the appropriate distance away from the bed or the bed surface is not suitable for polymer adhesion and needs to be treated with some sort of adhesive as you Slayer goes down I'm checking to make sure that all the printers movements are smooth if the extruder or the bed accelerates or moves too quickly then the stepper motors can miss steps leading to erratic movements if you observe these type of movements on your printer and I recommend turning down the print speeds and accelerations it's kind of hard to see on the video but as the filament is being laid down for the top layers of the cube there's a small amount of space between strands this suggests that the extruder is not depositing in a filament and thus the flow rate or extrusion multiplier needs to be increased the extrusion multiplier varies from filament type so it's not uncommon to have to adjust this setting in the slicer software I am guessing that this under extrusion will result in my cube being slightly undersized let's go ahead and measure it recall that the cube was designed to have a width height and length of 30 millimeters now there's going to be some irregularities in the 3d printing process so we can expect a small amount of air but too much deviation from 30 millimeters would indicate the steps per millimeter for the motors are not correct as predicted the x and y dimensions of the cube are slightly undersized I felt a little slack in zot X's x-axis belting which may account for it being slightly more often dimension than the y-axis I will fix this off-camera if the cube looks slanted in any direction then chances are your axes are not perpendicular to the print bed it's relatively safe to assume that once you have successfully printed a cube and your printer and firmware configuration files are set up correctly from this point on you shouldn't have to edit the firmwares configuration however you will have to edit the settings in your slicer to really hone in quality prints after the cube I always print the world's famous Ben Chee to determine what slicer settings need adjusting vinci is the perfect torture test for a new 3d printer because it has many different types of geometries after the print is finished I thoroughly inspect a little boat for imperfections from afar Ben she looks pretty good but closer up there are a couple of issues for example there was some indents in the bow of the boat that are indicative of not enough extrusion at the start of each layer and there is sagging in the arches of the doors and in the front window a sagging can be fixed by increasing the park cooling fan speed decreasing the extrusion temperature and slowing down the print speeds I've been 3d printing for a while so I usually know the causes for these imperfections when I first started I would have to Google my bench II specific problem and 9 out of 10 times someone else had the exact same issue and posted the solution there's about a million other things I could say about calibrating the settings for a 3d print but it's best to learn through experimenting my one recommendation is to stick with one type of 3d filament in the beginning because as I had mentioned filament made out of different plastics or even from different manufacturers will need different print settings in the next section we will unlock Sonic's his second extruder you know where his idec's gets its name well that's kind of an acronym there's a new breed of 3d printers on the market known as independent dual extruders unlike my maker gear m2 which has two extruders fixed to a single axis these new 3d printers have extruders that can move independently of each other one benefit of this design is that the second extruder can be moved out of the way when it is not in use I can't tell you how many times my dual prints failed I'll make a gear from unwanted using of the idle extruder this huge would get caught on the part that's being printed and after cooling it would obstruct the extruder that is printing which would often cause the part to get knocked off the other benefit to this setup is the ability to print two identical parts simultaneously by using both extruders at the same time I never demoed this on site X because the bed is too small but this is a really cool feature especially if you were printing a lot of the same parts now the connection design X's name is that independent dual extruder Tsar abbreviated as IDE X as far as I know all consumer-level IDE X printers only have independent x-axis nine X's extruders can not only be controlled independently in the x axis but also in the z axis hence why this printer is called Z X being able to control the Z heights of the extruders independently allows you to make sure that the nozzles are at the same height automatically with the use of a Z probe before we start setting up the second extruder let me quickly talk about the pros and cons of building a printer with an additional extruder the only column I can think of is cost IDE X 3d printers cost more to build because you have to buy more parts this is pretty self-explanatory but the hidden cost is usually having to buy a more expensive motherboard like the duet that can support the additional stepper drivers however most low end motherboards will support fixed dual extrusion and in that setup the only added cost is the second extruder and the extrusion drive in my opinion the ability to print multi material multicolor parts far outweigh the costs whenever I'm designing a model that I know will be 3d printed I try and design it in such a way that it won't require support but sometimes overhangs are unavoidable for this reason I always have a supply of PVA which is a water-soluble filament that can toss into the second extruder I will then set the second extruder to be in charge of praying the support material now for the prints finished I toss the part into hot water which dissolves the support structures even though PVA is pricey it's a godsend when printing complex parts with fragile features to be honest though I'm most thankful for my second extruder when I'm running late to get a print started and my first extruder is jammed around a filament I can just switch the print over to my second extruder and deal with the other extruder when I have more time okay that was a lot more talking that I meant to do the setup for the second extruder is identical to the first started most of it off camera this includes Auto tuning the heating system measuring the extrusion distances and printing the cube after these calibrations either extruder could be used to print apart however there was one last parameter we need to configure before a first dual extrusion print which is the offset between the extruders in dual extrusion prints the incoming extruder has to be able to take over from where the outgoing extruder finished for this to occur smoothly the distance between the two extruders must be known it can be awkward to measure the offset of the two extruders with calipers because yes you need to know the y offset but you also need to measure the x offset we don't know that these two extruders home to the exact same location on their corresponding axes I still try to get a ballpark measurement with my calipers we will fine-tune these offset values in the future with a dedicated calibration print we have to input these rough values into the configuration file typically the offsets are in relationship to the first extruder so we only need to list these X&Y offsets for the second extruder I had to make these values negative because of the direction of the axis and the offsets our first dual extrusion print will be a series of cubes stacked on top of each other the exteriors will alternate the printing of these cubes if the cubes are not perfectly aligned then the offset values need to be adjusted fortunately it is much easier to measure the alignment of the cubes with calipers I will repeat this calibration print three or four times until a transition from the red cube to the blue cube is seamless once I'm happy with the offsets I move on to printing a dual extrusion version of Ben Chi to fine-tune my print settings I start with a slightly enlarged Ben Chi because it is easier to print and a spot problems the most common issue with dual extrusion parts is the unwanted using of the idol extruder this is can be controlled by playing with the extrusion temperatures and retraction distance but these settings are dependent on the filament being used to avoid having to precisely calibrate these settings for each filament I recommend using a prime tower or a shield which is an additional structure that is printed next to your part this structure will catch unwanted uses and ensure the extruder is ready to print once I'm satisfied with this Big Ben Chi I will print the normal size Vinci and then typically I'm able to print other multi material objects without too much trouble I do print the offset calibration every now and then to make sure that the extruders are not drifting over time this section has been an abbreviated look at setting up dual extrusion prints if you've never attempted them ultimate to a part I'm sure that you still have many questions fortunately there's no shortage of dual extrusion resources online and I will write up some additional material that will be on my website this is actually a great segue into the next and final section on the many extra resources that are available to you when I was building my first 3d printer the biggest problem was I didn't know when I didn't know it was only when I encountered a problem did I realize wait a second this is not wired properly or oops that was their own component while I learned a lot this trial and error method there was a frustrating and expensive way to build a 3d printer my original goal was to share my previous mistakes that others can avoid them but then I realized wait a second I made a lot of mistakes so that original idea morphed into this massive video even with all this time it was not possible for me to fully explain all the concepts that go into 3d printing the perfect example of this is a stepper driver section you may now understand the importance of the stepper driver and how to wire a motor to it but the exact features offered by different separate drivers may still be unclear but now you know that not all stepper drivers are created equally and you can investigate which separate driver will be best for your printer to help continue your 3d printer research I've compiled all the resources I use to make this video on my website maybe you're ready now to dive in and build your own 3d printer but I've not decided on a prayer design well don't worry I have you covered I'll put together my top list of DIY 3d printers on the other hand maybe 3d printing still interests you but this video has scared you away from building a printer because of the complexity and time required if this is the case it may be better to buy a fully assembled printer I have also compiled my top list of commercially available 3d printers that are ready to go right out of the box whether you build or buy a 3d printer please consider posting your questions and prints on the dr. D flow forum my dream is to build an engaged online community around CNC machines where people can ask questions share their projects and talk about new technologies well that's the end of the video I hope you found it informative while not being too dense with the video this long there are bound to be a couple of regularities so let me know in the comments section below if you need clarification on any of the topics presented it wasn't just me working on this video I wanted to quickly vein Andy who helped at every stage of this little production and Eric who makes all the awesome dr. D flow animations I just finished building my garage workshop which is a huge step up from my previous videos that were filmed on the couch in my bedroom so make sure you're subscribed because I have a lot of exciting projects coming up [Music]

Channel: Dr. D-Flo

Views: 2,739,715

Keywords: DrDFlo, DFLO, 3DPrinter, 3D Printer, DIY

Id: qub5chyIQ0s

Length: 140min 52sec (8452 seconds)

Published: Fri Jan 03 2020