Designing for Assembly in Fusion 360 (Advanced CAD Tutorial)

in this video I'm going to walk you through some advanced tips and tricks for slicing models in fusion 360 for your 3d printing projects and this is an advanced itch tutorial on my techniques so if you're new to fusion 360 I highly recommend checking out my cat and UB series first but without further ado let's get started so why might you want to slice your models in fusion 360 once you've designed them well there's a couple of reasons number one is your print volume might be too small you might have a design that's quite large and you need to slice it up to fit your smaller printing volume number two is print ability now specifically talking about fdn 3d printers but this also applies to resin based machines too there's only so far you can push overhangs till they're too much and the print will fail so for some designs like for example this one you might need to incorporate certain cuts and break your model up to avoid using support materials that number three is aesthetics so for example you might want to slice your model up so you don't have to use support material because it leaves a scar on surfaces of touches and also under sight curves always look worse than topside curves when it comes to these 3d printing processes so you might want to slice your print for that purpose too another reason is assembly you might be designing an assembly that snaps together or goes together you put in you put components in and then you put it together afterwards that's a great reason why you might need to slice a shell up for example so you can print it and then assemble your project later and then finally color you might just want to incorporate different colors into your model and unless you have a dual color 3d printer that's kind of difficult to do if you're printing it all in one go so often what I'll do if I want accents and colors is I'll just print parts separately and assemble afterwards so I've broken down my techniques into two categories I call them the slide category and the rotating category in terms of how I break models up and I designed them to be reassembled afterwards let's start with the simplest in the slide category which is a plain cut I've talked about plain cuts before with slicing STL files but because we're in the a cat environment we have a lot more control over that cut when we're actually working in the model directly so this is a Steinmetz solid it's a two-sided Steinmetz solid this is credit using two cylinders that intersect each other I've shown these before on the channel and for this model look you would struggle to print it with our knitting supports there's no real easy there's no place to put it so what I decided with this model is to slice it using a plain cut so here I've got a plane and that's just a construction plane within fusion 360 now the cut tools up here split body now it's I call it plane cut because I come from meshmixer but in fusion it's called split body and to use this tool you need a body obviously a body to split and you need a splitting tool and that comes in the form of a surface now here I'm using a plane because a plane is a 2d surface but we can use surfaces in fusion 360 with the slip body tool to get a lot more control over that cut but the simplest by far is dumping your plane in where you want it and doing split body to get two pieces now we have these two parts like this but you might be asking yourself Angus that's great but I mean how do you align them you just mash them together in what glue them well basically yeah if you left it like this but obviously there's better ways to do it and the better way to do it is to incorporate indexing features which means when you put two parts together they lock together in some form that means they align and you don't worry too much about getting things precise using just glue or something or you know an ideal world no additional adhesives or fasteners at all and to create that indexing feature what I've designed in this model is this hexagon so you could just do a pin like a cylinder you could do a square and they cut through but I just done a hexagon here and the purpose of this is it's an extrude it's it's own little insert and I've also done an extrude cut in the original main body which means when we put the two together that hexagon will align both halves and make sure they're perfectly centered now when you design things like this there's no clear answers between the parts so if you printed this it's highly likely it'll be too tight to go together so I'm going to go through all my different techniques and then I'll show you how I add clearances back in at the end so here we have another example we have this sort of football shaped object and again we could just cut it and do an insert but instead I'm going to demo another technique you can use to join two parts together after slicing them and that's to insert a dovetail or like almost like a puzzle piece shaped cut that these parts can align into and lock together so to do that in fusion 360 you want to become familiar with these surface workspace so surfaces are zero thickness which makes them handy for designing shapes that you can punch through and cut things with so what I have here is this shape so this is simply a sketch that looks like a dove tail and a dove tail has that really characteristic pattern which have cuts in under itself and then to make this surface I did an extrude s as a zero sticklers extrude it is not a solid and we're going to use this extrude to cut our piece into halves you'd have to worry too much about how far it goes just need to make sure that it extends past the object on all sides and then we go we're going to do the split body tool again and what we're left with is our original part with that dovetail profile cut right through it so you can see if I hide one of these here I'm going to dovetail there and then the top one is here as well so that's how I add dovetails into prints when I want to print them separately and join them together it's a really great way to sliding onto a rail for example if you want to add it later or change it maybe have modular parts you want to slide in doing this technique is really good for doing that sort of thing and for our last slide technique I'm going to show you is using snaps now there are many other techniques I'm sure very creative ways to join things together but snaps something that's used in injection molding and industry all the time and you can use them too for your 3d printing projects to join things together I used snaps primarily for my assemblies where I need to put something together and it's like a complicated mechanism and I want to snap together without needing any fasteners so this is the inside of my rising golden ball making it that I showed recently on the channel and if I hide this piece here and hide the pulley you can see these little nubs right these are simply little revolves that in the part and the upper part has similar little revolves but these are a revolve cut and the way these work going to show you a cutaway is the parts come together the top part this blue piece deforms slightly and then snaps back onto those little little indents and that snaps the two halves together and keeps in place without that they would they would go together but they wouldn't stay together and this is a really simple way of snapping to things to in place and you can remove them using like a screwdriver to get between the edges and pry it but this is usually used for like a more permanent approach but keep in mind if you want to do snaps you need to allow some room for defamation you can't have if this part was solid on top for example you can't have snaps because there's no room for the plastic to bend and snap back I can't deform so you need to keep that in mind if you're going to use this approach but it's a really really good way to snap pieces together securely and it's very easy to carry and you just do revolve and for example for this piece is a revolve that I just patterned four times to get this result okay now we have our rotary techniques these are things that screw together in some way and first obvious example is a screw a screw thread so you can design screw threads in fusion even has a built in feature for it but I don't use it very often and I'll try to demonstrate why but again here we have that sort of football shape and this has been designed with a screw thread so we have two halves that would screw together so let me show you how we designed it again we're going to use the surface work flow to split the two parts using the split body tool but this time because it's rotary we're going to do a revolve using the surface tool so a surface revolve so here's our sketch this is what I've designed and edit the sketch and show you what it looks like and it has some very specific geometry built into it to keep printability in mind looking back on the dovetail example only one half of that dovetail approved without supports the other half would have needed supports this approach is designed to not need supports at all and I'll show you why we have this cut here and then it goes up here and then the angle is 45 degrees which is a very safe overhang angle and then it goes across on a shelf three millimeters now that shelf I'll remove later on with a chamfer to make sure that the top half has no overhangs beyond 45 degrees we're only using this profile to cut central axis for the revolve is here so finish sketch and I'll show you the revolve here we go this is what the revolve looks like we've got that middle piece coming out up across here and then that's the original shape and then we're going to do again a split body using that surface revolve which leaves us with this profile so it's like a mushroom or something so we've got this piece and we've got the bottom piece like this and that leaves us with these two halves that could in theory just go together but again they would be at a spin in place maybe with some friction you can force them together they're not gonna stay together there's nothing locking them in place so we're going to use the thread tool to make these two halves screw together but before we do that I'm going to change a few things on our geometry start with I did this this is using the press pull command I bought brought the bottom surface of the top part inwards by five millimeters so why do I do that well you don't need the thread to bottom out in fact you don't really want it to you want it to be tight and use the direction the friction of the threads to hold the pieces together but you don't you actually don't want it to be on the bottom of this bore here because there's a chance that there'll be you know 3d printing some accurate completely it's not a perfect process it's a chance that you'll actually end up with a gap or the two parts being together sorry it's out of that gap of five millimeters and then I did this which is adding that shaffer in like I mentioned so you imagine this part top half now it would print without support material before it would have needed support material for that shelf but now it doesn't and that bottom piece if we view it as if it was going to be printed yeah look there's not much surface area for that bottom part but that's why I had that three millimeter part going out otherwise it would be a sharp angle touching the bed we all know that that's not going to hold on to the bed it's not going to stay in here so this is a thin surface area to hold down but at least you could add a brim or something to keep it in place and these two parts would print without supports so let's add our threads in shall we starting with the bottom half so you go to create and thread and then you drop it in on a face which is this one here and it's very important to tick models otherwise they're just aesthetic they don't they're not actually part of the geometry they just look like there's threads on which is normally how people would design stuff in CAD because you don't usually like machine threads directly from the geometry and the CAD program usually like machine them later using a tap or something but because we're 3d printing we can actually put them into the file and the geometry itself so we're going to model them in it's very important to choose a size that you can use on both sides now it's going to try to adjust to one that works for you and it's Auto chosen 40 millimeters here so size is 40 and designation is 40 by 3 so the pitch is 3 it goes up 3 millimeters each rotation and you can change that to a final pitch for example 2 millimeters but coarser is better when it comes to 3d printed threads so going to keep it at 40 times 3 and direction you can if you want a left-hand thread absolutely just make sure you make both left-hand I'm gonna leave this like this and then okay so we have a fully modeled thread and I've actually gone ahead and done the same for the top half as well with a different feature you can't do two at once two different bodies but it's the same size you're gonna make sure you choose the same size thread otherwise obviously they're not going to thread together are they so we're done that and something you'll notice straight away with the cut through analysis tool is I don't line up you can see here the threads it looks like it's not going to work don't worry about that just determines where they've started and finished the only time you should care about this is if there's details on the surface of the parts that need to align and in which case I do not recommend using threads because they will tighten up to a certain point of friction and you can't predict exactly where that will be so only use printed threads coarse ones when you can screw tonight together it doesn't really matter where the two parts end up in relation to each other but there you go you can do threads like that but a technique I much prefer is to do a sweep and revolve that sweep to create a thread like geometry that's actually much easier to 3d print so I'm going to show you that so here we have a cube now normally a cube would be easy to thread eprint but just for sake of demonstration what i've done is i have cut this cube using the sweep tool again CAD for newbies I've shown sweeping before and you can actually add a twist angle to that sweep the cool thing about this model though is we're using a surface to do our sweep so here I've got a profile at the bottom which is literally just a spline I've just gone a problem to make sort of a dovetail ish spline on a sketch and then I've swept that spline up a nother sketch just to line up the middle and I've rotated that sweep with a twist angle of 180 degrees so that means it's gone full 180 from the bottom to the top and it's resulted in it ending up at 180 degrees on the top of the corner of the cube itself so you see it's lining up there nicely because I made sure my sweep path or rail depending what CAD program you're coming from is aligned straight from the bottom to the top of the cube as well that's important if you're using the twist angle it's along the whole length of your path so make sure the pass the right length so that's pretty cool we've got this really neat looking sweep and we're going to use that sweep to do a split body and the resulting shape is amazing I love doing this other thing look how gorgeous that is so these two parts will slide together top to bottom they'll slide together and end up with a solid object it it's really elegant they'll snap together although they'll probably they can still keep sliding if you don't add anything to stop that but they won't pull apart as such so this is a great way to add things together and Devin over it make anything use this twist technique to do these twisty verses where like these little and fidgets spinners are software you had like a really interesting outside profile and parts that went together in and out looks really cool go check them out he did a whole video series on them and I actually use that technique to do a puzzle back in 2018 this is my puzzle cube and you can see all these parts have been cut using a sweep and they look like they shouldn't go together which is really cool like they look really strange but they do they do completely go together and that video is here if you interested and that file is up for free on my podía store and it's really it's a really fun puzzle it's actually harder than you might think so to recap you can sweep a surface and actually add a twist to that sweep if you like to make parts rotate as the index together to join into a final model okay now it's time for in my opinion the king of rotary joining methods this is something I use a lot on my more recent models it's a more challenging approach to modeling a joining technique but it's by far the most satisfying so here I have a rod and here I have a cap and the rod has nubs on it and the cap has grooves that match those nubs and what happens is you put it in and then you rotate around and then it's permanently locked in place really really satisfying I used it on my my rising golden bull 3d model and I'm using in this new model that I'm gonna release soon so I've rolled everything back to the beginning and let me show you how I design these parts and I'm gonna start with this sketch now this sketch is used to define the nub on the part that's inserted and rotated and locked into place but also the path that it follows on the other part so I use the same sketch for both and that's important because it's easier and it means if you change this size it'll update both parts so this sketch I created the first revolve cut and this revolve cut was done using the central central axe of this cylinder as the rotating axis so rotated around and it's important because you can determine how fart rotates using an angle think this is 80 degrees it doesn't matter you can choose your own angle to line up with something which is why it's good to use this technique to index things accurately if that you need to line up versus a thread which is really difficult to perfectly line up things because it just it's when the friction bites in versus this which is when it runs out of path which is my preferred method and then from here I did the nub so you can see here with a central rod I've got a another revolved as a revolve join us it's adding material and it's just using the axis and the center of the circle to add a sphere onto that rod the next step is to allow for that actual rod to go in and then rotate and stamp into place so you need to add a path for it to actually go through so again I use the same sketch which is why it's got this big rectangle attached I use that profile to cut this detail here which means as you can see down here that that little nub will come down and then rotate around the part and then lock into place and then as a final touch and this is optional I actually added another sketch which is on this face here right at the end of the path and I just revolved that to make a nice rounded cut so the actual nub can go all the way the end this is a little bit pedantic you don't have to do it but it means it will rotate the full 80 degrees versus a little bit less because it would hit that hard edge now for most people this is probably totally fine we can do a rotary pattern and we're good to go but what I found with this piece originally is let me show you here is I was had trouble getting the friction to hold it in place you can see it's very easy to just go in and come out so I want to add another little nub in place that it sort of pushes over and jams into place which is what this little detail is here getting these right size is challenging this little nub here it needs to be small enough that it can just be kind of pushed out of the way because there's no room for defamation but big enough that actually locks it in place we're just adding something that will just kind of be a sacrificial bit of a catch kind of so when it pushes past that it's very unlikely to ever come back out and once you're happy with that you can just do a rotary pattern to copy all those features around so you have a good uniform distribution of points where you can insert the part and rotate it and lock it in place and luckily fusion does rotary patterns with features quite reliably actually it's quite good so I've got adjust here which seems to work quite well as the compute option and I've done three three points you can see here now we have three points of entry so I'll have three little nubs that go in and rotate around to lock into place just like that okay so let's address the elephant in the room these parts have no clearances none at all which means if you try to print them like this they're likely to be too tight now sometimes you want them to be tight you want a friction fit and it when it comes to parts like this you might get away with zero clearance however that is very dependent on your printers accuracy and quality and what type of geometry you're going for so how I add clearances into my models these days it's incredibly simple let me just show you it's using the press pool command this is by far I found the easiest way to add clearances and modify them should you need to so you select the object you want to add a clearance to so this is all little nubs and the rod itself so all you need to do is now add in the clearance that you want and we need to offset the services inwards in this case so we're gonna add a negative 0.1 millimeters this is going to be a tight part I want to be tight if you wanted lots of clearance and you wanted parts to be really free you might do a point two or 0.3 even or offset both by point two so you end up with a point four gap overall up to you really is up to you how you find what works best for you so I'll say ok with that so you can see here we've got a nice clearance of 0.1 millimeters which means the parts will not be too tight and you can adjust that easily and it's probably the best way I've found in fusion to add clearances to your models for 3d printing so thank you so much for watching I hope you learnt something new about creating parts that are in pieces in fusion 360 and joining them together later for whatever purpose it might be whether to make it easier to print or to fit your print volume or for aesthetic purposes or to assemble a complicated piece later on I'm gonna leave you here with this picture this cutaway of a model I'm working on it's for Easter this has been one of our one of the most complicated models I've ever worked on to get right and it's got all the tips I mentioned it's got the screw threads joined together it's got a rotary sweep it's got offset it's crazy stuff so I look forward to showing this letter and it on the channel and if you want to see more featured content like this please let me know in the comments that you enjoyed it and you want to see more and also maybe because it's subscribing so you don't miss it thanks for watching guys bye

Channel: Maker's Muse

Views: 109,757

Keywords: 3d, printing, cad for newbies, fusion 360, designing for assembly, design for 3d printing, adding clearances, maker's muse, makersmuse, angus deveson, australia, tutorial

Id: FzCm1iTf8PA

Length: 23min 0sec (1380 seconds)

Published: Wed Mar 25 2020