How We Made A Wire EDM Machine At Home

last week we built a diy edm machine and today we're building a diy wire edm attachment for our cnc machine because it's coveted and we have nothing better to do so subscribe like and let's get started here we're looking at the final design i'll explain why we designed each piece the way we did as we go along alright step one before we invest in making a rigid metal frame i decided to 3d print this design just to make sure everything works as intended this was far too big to print in a single print though so i broke the design into five components each of these components has a key and a hole so they can slide into one another precisely where they're supposed to when preparing the prints i selected to print them with one hundred percent infill to ensure they're as rigid as possible unfortunately this made the print time for each part about two days long when the prints were finally done we assembled the frame into a single component and no glue was needed as the pressfit did the job really well next we need to add some threaded inserts into all these different areas of the design for now let's add these threaded inserts instead of tapping into plastic i'll just heat these up with a soldering iron and drive them in if you want more information on this process feel free to watch our diy spot welder video where we explain this in more details i repeated this process for all the threads which took me no more than two minutes and the outcome looks very promising at this point we get into the fun part where we begin to work with the brass wire mechanism this brass wire will travel all across here so let's start installing the wire guides our primary drivers are these special metallic honey dipping sticks don't let the simple design fool you though there's actually quite some science that went into conceptualizing these their primary function is to generate as much contact area as possible with the brass wire in order to prevent any slipping these mount into two bearings one on the front and one on the back of the frame you should probably use a press to fit them but my hammer did just fine with the driver rollers now in place let's move on to the guide bearings these are just groove bearings which help transfer our wire around the frame passively they spin only when the wire is pulled by our driver rollers and their groups guide our wire precisely where we want it to be i have three different options for these guided bearings the first one in the middle is a ring machined on a lathe which has a perfect fit to any standard 22 millimeter bearing i'll take a second to thank pcbway.com for sponsoring this part of the video by waving the 300 price for 10 of these parts i simply uploaded my cad design on their website and they sent me these parts a couple weeks later at that price per piece so i had to find an alternative i wanted to make this as affordable as possible for you viewers to replicate so i found these grooved bearings at ten dollars per piece but while the price was okay it was very hard to rotate these so we have a classic scenario of too hot too cold and just right i found these tiny grooved bearings for just two dollars per piece which rolled very easily with our brass wire now that we know which idler bearing we're going to use let's install them onto the threads note that i use a washer to properly space the bearing from the frame as per our design so all our idler bearings are now installed which means that we can move on to properly mounting the drive rollers the way they stay in place is via these gt2 belt pulleys which we install on the back just tighten the set screw with an allen key onto the shaft and you're done these pulleys will spin in sync by use of a timing belt and a nema 23 stepper motor i'm also adding a belt tensioner here for good practice the motor is going to be situated right here however before we tighten the belt i want to install the brake system the way this works is we have a brake pad which we put on a pivot or a shoulder screw in our case let's put our spacer washer in and install the assembly all right now there's our brake pad so as we pull it down it's going to apply more friction on the drive shaft to pull on the brake pad we use a 25 kilogram servo which is the conventional servo you find in remote control vehicles to couple these we'll use a spring using rigid coupling can break the plastic brake pad or overload the servo motor so this way there is give while still pulling the brake pad onto the shaft we now need a high resolution 3d print of all the pieces seen in red the first step is to throw all the designs into preform where we can set up the prints as you can see i've added supports under some overhangs and i'm pretty happy with the way the print outline is looking so we transferred over to the form3 printer which took just a few hours when the prints were done they looked perfect we gave these parts one day to cure and separated them here into left and right the right parts will go on to the final metal frame and the left parts will be on both our prototype and the final product you can see we've already threaded in the nozzle and cooling system so these parts are all ready to go now this is the part that goes up and down as i'm showing here in the cad model this works with these tiny linear rails which slide right into our part and then again we take the nozzle that feeds our brass wire and we thread it onto the part we also thread in a quick connect for the coolant tube and tighten these both down with a wrench and that's it the assembly is done simply screw on the cap which guides the coolant right past the cutting wire and we're ready to go and install this on the main frame the way this works is by installing the slider onto the frame with four screws the holes are already present in the frame now just slide the rail into the slider and we're ready to move on to the bottom part as you can see we already threaded the nozzle and coolant parts so all that's left to do is mount the entire component with two screws onto the main frame wow everything's actually working perfectly so far and we're almost done all that's left now is to install the electronics and write the software however now that we've come to the end of the mechanical part of the video let me just conclude by saying that we've actually had these parts molded and mass-produced so if you're looking to buy them you can purchase them directly from our website we're also sharing all these designs for free on our website in case you want to just replicate it on your own so make sure you check out the description below for more details oh also please please please hit that subscribe button below we don't want you missing any similar videos that we are going to be launching in the future a like would also be nice okay let's turn this around and install the stepper motor right here we're using a conventional closed-loop nema 23 stepper motor and the driver that came with it the set was about 120 us dollars on amazon mounting is really quite easy we just slide the motor shaft into the timing belt and we use these stainless steel spacers and screws to install the motor into its intended spot on the frame yay the motor is in place but the belt is a little loose this is where we employ our belt tensioner just to make sure the belt doesn't slip over the teeth of the gears and that would be it let's quickly connect the motor to the driver now this is super easy to do because the motor tells you exactly which wire by color connects to which terminal on the driver so we connect the four motor wires followed by the six encoder wires and we're ready to move on to our tension sensor these sensors will dynamically inform our controller of whether the wire is tight enough or not which will engage the brake accordingly to increase or decrease the brass wire tension we mount these with just two m5 screws and we have two of these sensors one for the re-spool mechanism tension and one for the cutting surface tension but i'll explain those in more detail shortly for now let's connect these sensors to their analog digital converters which we can use then to communicate with the arduino nano as i had done in this example the analog digital converters or adc come with the sensors and the arduinos well they're cheap enough to buy on amazon i got three for around 18 usd we're going to end up using all three arduinos so for simplicity i'm going to physically attach them to their corresponding adc using some super glue and this worked rather nicely now i'm going to make some soldered connections here but i'll save you the time and skip over to the finished outcome which as you guess turned out good so i completed the second one and connected both of these to the sensors which means that now we can move on to the software unlike our fully automated plastic injection machine which we made a video of this machine only runs arduinos so writing the code is really easy using the arduino ide all this code does is read the tension from our tension sensor and changes the output signal to our brake servo or stepper motor for the re-spooling mechanism let me quickly pull up the arduino serial plotter and show you how our tension sensor is working you can see here that the analog values the arduino is reading are proportional to the amount of force i apply on the tension sensor so we can conclude that this is working properly here it is up close again awesome we're all done with the software so to wrap up we just need to make an enclosure for the electronics once the general design is done we digitize the electronics to make sure they fit in our small cavity and well it turned out perfectly at least for our purpose so we played around with the layout to ensure everything fits and then we 3d printed our electronics box we now need to fit all this mess into here so i'll do that offline and be right back while i was at it i also added potentiometers to the arduinos which will enable us to adjust the tension controls these are mounted with an lcd screen onto the front panel although i'm not going to configure the lcd readouts until our final version of the wire edm otherwise we're all done here so let's connect the power and start spooling some brass wire for a power supply i'm just using a 36 volt switching power supply that i got from amazon for 16 dollars we bridge this power supply between our two stepper motor drivers and drop 5 volts towards our arduino control box the second stepper motor which i haven't mentioned yet is related to the brass wire respooling mechanism which is what i will get to very shortly but before respooling we need dispensing to do both dispensing and re-spooling we developed these 3d printable holders one of them is passive and rather simple as it just holds the spool of brass wire but the other has a motorized system so let's start with the simple white one first we printed the files which are available to download on our website next we need to install the rotating shaft or the spool of brass wire this shaft sits between two roller bearings one on each side installing these is super easy just place the bearing over the hole and press it in with any clown we designed the tolerance to allow for any easy at-home press fit sweet all done the rest of the assembly is quite intuitive however note that the shaft can still slide in and out so we need to add these caps again to add the threads we use this insert trick with the soldering iron but you're already experts at that so i'll save you the details now we install our second cap and the shaft is locked in place a final test and we're ready to move on our wire re-spooling mechanism is built the same way as the dispenser but you would note a stepper motor down below which will collect the wire only when the tension drops hence by closing the loop with the tension sensor we can ensure very consistent results so we print this component and press the bearings in we install the shaft and cover it with the cap on the one side only the other side has a custom cap that allows the smaller shaft through which is where we attach our belt pulley note that we mounted the stepper motor in slots which is where we adjust the belt tension with the re-spooler all done let's bring together all the pieces and get ready for our first test cut and there it is the finished product it starts over here with the spool of unused brass water the wire is fed all through this contraption before being excreted and collected with the respooler this despooler is driven by the stepper driver which receives its commands from our control box to feed our brass wire into the mainframe we use clear teflon tubes these push into their designated holders on the frame to fit the brass wire into the teflon tube i found it's far easier to just fold the brass wire in half and then push it in otherwise the brass just kinks and doesn't travel further into the teflon tube now we can guide the wire through starting with the brake rollers around the first tension sensor and then into the orifice the orifice may be hard to see as it's only 250 microns in diameter the wire diameter is also 250 microns which makes it practically impossible to pass through the hole to solve this here's a neat trick pull the wire tight and then expose it to a flame as the brass heats up it will stretch until it tears and what you end up with is a very pointy brass wire which is far easier to fit into the orifice let's quickly do this to our actual wire and then feed it through the orifice now do this to the bottom and our mini banjo is ready next we pass the wire around these passive rollers and finally we wrap it around the feed rollers which will pull the wire across the entire setup and then channel it through the teflon tubes into the re-spooler a neat trick i use here just to start a new spool off is to wrap the brass wire around the stainless shaft a few times and then tape it down otherwise it just slips all right let's test our system in three two one bingo next up we need to cut some metal but first a summary this brass wire is passively fed into the machine and as the wire enters it's fed into the brake rollers these rollers have four grooves on them and pass the wire back and forth in order to increase the surface area between the rollers and wire which increases total friction so the wires won't slip we could have achieved the same surface area with a bigger wheel but instead we offset the groove on a smaller diameter these pass the wire from here to here to here to here to here this is actually a great design in my opinion but feel free to counter in the comments we always respond from here the wire travels to the tension sensor and this is the sensor that measures the tension on the actual cutting surface we then have our idler bearings which do nothing but guide the wire around the frame into the drive rollers these are about the exact same way with the one two three four grooves and as they excrete the wire it passes across our second tension sensor which is used for the re-spooling mechanism from here the wire is fed into the d-sphooler which rotates at different speeds faster when the wire is loose and slower as it catches up and tension increases and that's it we're ready to cut so let's connect our power supply one pole is attached to the piece we're trying to cut and the other is attached to the brass wire we're going to add these to our guide bearings which will not affect them under normal operating conditions after connecting our first wire down below let's also extend it up to the top for a more equal distribution of current across the cutting wire we're using the same power supply we used in our diy edm sinker and you can get more details about it on our website all right so here's our little contraption which i've mounted on an old diy cnc machine of mine i'm going to be converting this machine into a wire edm machine because i no longer need it since we built our massive diy cnc machine as you can see in one of our other videos it's an awesome video so i'd totally recommend it now this machine here runs mach 3 which you can see here and those of you that may be familiar with mach 3 would notice that the display is a little different this is because i'm actually running a 5-axis custom version on here but it doesn't matter all the axes still move the same so now that our contraption is mounted on a very accurate three axis motion system we're ready to bring in the deionized water and do our first testing cutting some metal so the first thing we need is a little container which is essentially going to be our cutting bath that's going to go right in here next we're gonna fill that up with deionized water and i got a whole bunch of these from canadian tire so let's get going so we've added our canadian deionized water eh now don't forget to use the appropriate safety gear such as gloves and of course goggles eh for a quick test i'll put together a jig to hold the metal rod after we plunge it into the water and connect the other pole of the power supply to it we're ready to start the brass wire feed note these black marker lines i drew on the rollers to help visualize the rotation and here we go test cut number one of course it's always two steps forward one step back i wasn't sure what happened there until we slowed down the video and saw the wire got snipped by a powerful spark to confirm we took a closer look and indeed we can see some slight erosion well a broken wire means that we have to lower the bathtub and reroute the wire once done we try again but this time we move the mechanism at just two millimeters per minute instead of six it definitely looks much better but of course the wire breaks again taking another closer look we can see a more evident gouge which gives us hope to try yet again this time we're adding the caps and water pump to flush all the loose material away from the cutting zone this did not seem to work any differently than the last attempt even though we tried again and again and again and again during all these attempts i had lowered the current setting on my power supply to the lowest but i still felt that the spark per area of wire was too big i thought that perhaps increasing the cutting surface area would help so i tried to use a one inch square rod of stainless steel while it lasted much longer it seems that something more fundamental is the problem here all we got at the end was a permanent black line on the steel but we weren't quite ready to give up we wanted to know whether our current just consumes the wire too aggressively and after making some sparks we notice that this wire gets consumed far too fast so we decided to remove our wire contraption from the cnc machine and use a thicker piece of brass for comparison all we had to do was load it into our cnc spindle and lower it at a rate of one millimeter per minute note that we have the water pump flushing away the swarf which is the black residue as i learned from my viewers comments on our previous diy edm machine video i guess i'm reaching out to you all again to ask what's wrong with our wire edm contraption let us know and we will build a second version with all of your commonly suggested answers as time went by the dns water got really dark so i wasn't sure if there was a point in continuing we stopped the experiment and sampled the water which i've now learned has to be filtered if we're to build a proper edm machine you learn by failing what else can i say and there's just one more important thing subscribe and like please you

Channel: Action BOX

Views: 649,957

Keywords: CNC DIY Homemade Wire EDM Machine, CNC, Wire EDM, DIY CNC, Homemade EDM, EDM sparks

Id: 2ewSbI52ICc

Length: 18min 45sec (1125 seconds)

Published: Fri Jan 07 2022

Reddit Comments

[u/chiraltoad]

Awesome. You guys are impressive.

[u/SneekyF]

Dude! I just saw this video on YouTube this morning. So great keep it up. I sent it to all my friends (one) liked and subscribed.

[u/Alwaysonlearnin]

Well done! Wish I had an answer for ya!