FreeCad Tutorial #12 | Design a functional Snap Buckle in FreeCAD for 3D Printing

hello and welcome back to K-Tech designs my name is Seth in this video I'll show you how I made this snap clip in freecad I designed it for 3D printing and for it to be actually usable so in this video I'll show you how I made the male half and the fitting female half of this clip and with that let's get started so as always let's start from the home page and let's create a new part let's change our workbench to the part design workbench I'm going to create a part container and then we'll create two bodies within that container I'm going to rename this one to mail and the second body to female let's get that e in there all right now with the mail selected let's start a sketch and I'm going to sketch on the top plane now this sketch is going to be the most complicated part of this so bear with me let's start with or I'll model the mail end on this side of the vertical axis here so let's just start with a rectangle we'll get the the basic shapes out of the way and then we'll start with the second rectangle this way and then I'll make a sort of an Ops offset there Let's uh make these coincident if I can pick the correct type and then let's trim this middle add some symmetric constraints here and we'll go ahead and dimension this to 22 millimeters long make those coincident gosh make sure you click click in the correct parts and I'm going to make these two equal that needs to be vertical all right let's drag things closer that's better so let's dimension this outer body here 25 millimeters and I'll make those symmetric as well okay starting to take shape let's Dimension this leg 21.5 actually that is just 20. so now that's our basic shape let's Dimension this leg here to be four millimeters and actually I'm going to need to offset these so let's just draw a little line here and then I'm going to trim this leg out oops and delete that leg and this needs to come up a little bit about a half millimeter there we go okay now we're ready to model the flexing snap feature which is one of the most important parts of this design of course uh actually let me just quickly Dimension these it's just um three millimeters thick [Music] okay that's locked in so you're just loose I will make these equal okay I'm actually going to come back in and do some fillets but I just want to lock down that shape to begin with so we got this leg here and this leg here now we need to draw some arcs do this one this one draw a little one at the tip and then one more here and let's draw our locking leg and we'll draw a tiny tiny leg up this way put an arc on there I'm going to add a tangency that should have been vertical second tangency oh I see sorry about that I'm gonna have to delete all of these because come on I missed to mention that completely let's try this again so actually this leg is 22 and this should actually be back a half millimeter so I'm going to grab these two vertices here 0.5 yep and then these two vertices should be 20. there that looks right all right so let's go back to our snapping latching feature and let's add some tangencies uh it can be tricky adding tangencies to Parts uh sometimes the program gets really confused on where the tangent sea should be and you'll get really funky geometry so if uh if it breaks you just have to start over like the there's no there's no way to fix it um but that one turned out well uh looks like that I I picked fairly reasonable points and the program was able to figure it out so now this we need to keep track of this thickness this is an important part of the design and then also this Gap here so as the part fits into the female part it's going to have to move a certain distance so you need to make sure that this distance is not longer than this otherwise you can't Flex apart out of the way and this part needs to be sufficiently thick so that it can Flex um you know not too thick or else it won't flex and not too thin so that it doesn't fail with repeated flexing so let's say make these two endpoints symmetric let's make this radius 3.5 millimeters oops let's make this radius nine millimeters let's make this angle 45 we'll make this height one or sorry two millimeters oops don't do that this radius should be one millimeter okay and I did not Dimension a radius on this part for this part what I did was I well let's just go ahead and select all of these edges oh my gosh uh even these two we'll select our horizontal axis and let's do a mirror okay these points are not going to be connected of course so let's get them all connected and so what I did was I made a line between these two and then a dimension this point to this point at 3.5 millimeters so now we need to Dimension this leg thickness so let's add another line I'll just make it uh radial like that so that we have something a point to grab onto we'll grab those two vertices and we'll Dimension 1.5 okay and then let's do the same kind of deal over here for this tip that way we have a tangent point to grab onto and we'll Dimension it from the vertical axis 2.3 millimeters it's getting kind of busy here and then finally I'll just add a dimension here and that tip and we'll make it 11. so now that feature should be pretty locked in except for its uh width here I'm going to add some symmetric constraints as well I'm going to add in another tip control here and so we'll measure from that should be horizontal okay so we'll measure from this point to this point vertically 15 millimeters all right so let's go away let's make these symmetric as well all right that's looking pretty good connect those two together add in a tangency I'll also make these equal right away before I forget so let's make these 20 millimeters apart not sure what else is missing a constraint oh of course these two uh tip points should be symmetric and those are equal already I'll just take that off so I can make these equal hold on hold on what happened I lost the constraint this is what the heck That was supposed to be 3.5 now these two corners I should be able to dimension to two millimeters so I must have must mess something up in this sketch somewhere oh let's get that uh out of the way that's supposed to be to here anyway two uh sorry three what what okay I'm just gonna add in this line here okay that locks it in place as it should be uh I don't understand why these aren't going to two millimeters other than having this leg here it could be an issue let's see if I can just do one because I have both two okay that works perfectly oh they were already equal maybe didn't like that all right sorry for um that distraction I'm adding this in seems to be all it really needed and making it tangent so that these points were truly at the Apex of this curve all right so we're done with the the clipping part here I'm going to add in some sketch fillets uh I've started to use more and more sketch fillets let's do a sketch preserving or a constraint preserving Sketcher lit um because the the filleting feature just just breaks all the time that topographical naming issue is just too much for me to deal with so if you need to fill it put it in the sketch all right so I'm just gonna touch these uh lines here another fill it in area should be here and here um let's uh let's do the tip here as well and that should be good so now these two should be equal and they're 0.5 millimeters these two are equal and they're one millimeters but I'm going to make them equal to these inner ones as well because those are all going to be one millimeter thick or one millimeter radial one these outer ones are all the same so I'm just going to grab these three and make those equal I probably lost a constraint or two so let's bring this back in okay so that should be vertical all right that wasn't too bad that looks good let's close that let's create a pad and I'm going to make it six millimeters tall click OK you can see that most of the work was done in the sketch and now all I'm going to do is I'm going to add a cross member here and I'm going to add some rails on the top here and this helps ensure that when the clip goes in it's fairly straight and it doesn't wobble back and forth I noticed that in my first design without having these rails on the top that you could actually move you could rotate this part inside the female part enough that one of these edges could come out and then the clip would fail so having the rail in the middle and then of course the feature on the female part that uh retains it will keep it from rocking back or rotating inside the female part so let's do the cross member next I'm going to do a sketch on the um front plane here just going to draw a rectangle close that uh not close that uh hide this part and then we're gonna I'm going to add a split split Edge and I'll make these two edges equal and that way I can Dimension to the middle let's make that distance 32.5 I'm going to make this overall height three millimeters and then we'll make these make the width 4.5 and I'm going to add a sketch fillet on the top edges here and we'll make those one millimeter okay close it bring back the visibility of the pad and then we'll do a symmetric Extrusion I believe that's at 19. don't know why they didn't update visually but you're just I'm just making it the same uh length of that inside there and the reason why I've modeled it this way is because this plane represents the printing plane since I want to 3D print these and I don't want to have any supports obviously if I printed it like this then I'd have to have support material under here um but I want this to be smooth I don't want it to have uh remnants of broken away support material all right so now let's make the rails on the top I'm going to add a sketch on the top plane I'm going to close it and I know the part is six millimeters thick so I'm going to change its attachment to be six millimeters above the top plane go ahead and edit that sketch and these are going to be pretty simple I'm just going to add two long thin rectangular features I'm going to Dimension this to um one millimeter its overall length is 20. and its thickness I'll do it this way is also just one millimeter I know that this leg is four millimeters thick so I'm going to Dimension these sorry I'm gonna make these symmetric and then their Dimension will be four um those are that way let's make these equal and these equal as well and that finishes that and then we'll extrude them pad only needs to be a half a millimeter tall it's just something above the the rest of the part that I can use to be a retainer click OK on that and then I'm going to add some sketch chamfers on here oops I just need one we need to do 0.499 because you can't do 0.5 on a 0.5 leg which makes zero sense but that's how it is and then we'll grab all of these edges perfect and now that half is done mail end is uh ready to print so like I said most of the complexity was in the sketch because I'm designing it for 3D printing I don't have a lot of complexity options in the first place so you know it's going to be a simple boss extrude boss extrude with the retaining features so let's go to the female part I'll double click that body so um all new features will go there so let's create a sketch on the top plane and this is going to use a a shell feature so we're just going to create a box here roughly same size as this part what's dimension from that vertical axis oops 22.3 millimeters I want a bit of a gap here so that the part is able to slide fully over and past this tip but not too far because I want it to uh to actually latch nice to mention this back leg to four millimeters then I'm gonna make these symmetric and their length is 25 millimeters now when we extrude this pad we're going to need to do it in two dimensions actually first let's bring this sketch down one millimeter for clearance let's go back to the pad we're going to do two Dimensions this top Dimension will be 9.5 and the bottom Dimension will be 1.5 now for this one I am going to put a radius on the outside edge first and that's because I want the shell to have an inside radius okay so two millimeters on that uh sorry 2.5 millimeters on that radius so now we click this face and we'll come over here and click thickness and I want the thickness to be just two millimeters does seem wrong oh uh make sure that you're pitching the direction of the thickness the thickness will be inwards meaning that your sketch is your outer boundary not the inner boundary so that looks pretty good that'll be nice and tight but also not allow a lot of Motion in the part in the fit click OK on that so let's hide this male part for a second here I'm going to grab this inner Edge and I will put a fillet on there it doesn't need to be very large 0.7 and that's for dealing with a future feature that I'll have to add on there now let's bring the mail part back in and we need to create our cutouts you know the latching cutout and also where your fingers will compress the tabs um and it a convenient way to do that actually is to take this male sketch let's go to the draft workbench and we'll go ahead and clone it drag that back into the female now what colonian does and I didn't actually know this until mango jelly showed me how to do it uh when you clear I mean I knew how to create a clone but I didn't know that it actually will be a live update of the sketch that is cloned on um and that's extremely convenient especially for the way I'm going to use it now as a reference for um where to put these cutouts so thank you mango for a very simple but powerful uh tip there all right so let's create our cut outs I'm going to go to oh we gotta go back to the part design workbench let's create a sketch on the top plane and I'm going to hide this model um and let's hide this model and now you can see our sketch is visible and we can copy some of the important edges here also we want this one and that's probably it because I can mirror the cut feature so let's start drawing the cut feature I want a straight leg here and one here as well I'm going to take this reference geometry here for a tangency control and then I'll add an arc between this point and this point so let's make these tangent let's make these tangent and I'm going to make these parallel and then I'm going to dimension now see how that won't work so I'm going to add in another reference line construction line and I'll make that perpendicular to our reference line and then I will Dimension this to 0.5 millimeters and again that is just to create some clearance between the parts so that they slide together but I don't want a lot of clearance because I want them to actually lock together so I'm going to take these sketches here I don't need that one and that will create a mirror mirror that geometry let's make these equal right away I'm going to make these symmetric or is it sorry and I guess I'll make these equal as well so now we can Dimension this to 25.1 and if you remember 25 is the overall length we're using for this part and I've noticed that sometimes when you do size on size cuts there will be an infinitely thin plane still visible so I often cut over what the part actually is just to ensure that that plane doesn't happen um let's create um another one of those tangent features here well I'll just Dimension it right away and maybe I don't need that one the spacing between them is six millimeters sorry the spacing to the axis is six millimeters so I must just be missing like an equals here and then possibly a symmetric to make sure that there are that they are parallel I must have an extra constraint somewhere probably the equals here nope still not right I'll see I want those equal hmm maybe I have to get rid of one of these symmetrics here like this Outer Edge one oh somehow I've lost my parallel on that oh those weren't actually tangent sorry about that all right that looks good bring back our visible parts um we can hide that for now and then let's do a cut and I'll do a through all reversed and then I guess I'll I'll change the position of that sketch wrong direction so let's do like negative three all right so that ensures that the the part is fully cut through so that's looking pretty good here you can see we've got quite a lot of distance of overlap here so we'll have a strong clip so I'm going to add a few chamfers we'll chamfer this surface here sorry what did I do oh it's too big I'll make it 0.6 so this chamfer obviously is just to make the part insertion easier you could even come in and do a chamfer on this top and the bottom at the end of all of this instead of just the way I did it there but it's a little flaky so I didn't do it I I just relied on the fact that the extruded material is not going to have a sharp edge um it's going to be a little bit rounded anyway all right so then I'm going to add a fillet to this edge here and this one as well one millimeter is sufficient let's create this pad on the end here this one will be easy because we modeled this pad on the top plane this one can also be on the top plane and merge nearly seamlessly uh so let's just make um two uh rectangles here and then I'll trim out the inner leg okay um we measured we Dimension this to four millimeters earlier so I'll just plug in four there the overall length should be 19. and the wall thickness is three just like the other one all right and then I will add symmetric constraints as well I don't really need that I don't need this one I don't know what that came from oh boy what did I add I'll undo okay oh there we go sorry I don't know what I added there was a weird we'll make these symmetric as well interesting connect those and then make this vertical okay and then I guess we'll make these equal oh I lost oh I don't know if I even added that this should of course be 25 okay so that gets us to the edge then I'm going to add some fillets here these two being equal and being one millimeter and then the outer ones also being equal and begin two millimeters okay set those equal again because I guess I deleted them when I added that fill it close that pad that six millimeters and that looks good and you can see that I picked a radius here that produced a nice solid line it's uh it doesn't make the design good or bad it just looks good now let's add in our cross member so that's front plane I'm gonna hide that again it's just a rectangle on the top plane uh let's uh split that as well make those split lines equal uh the overall width is 4.5 millimeters the overall height is three and we'll make the distance 12 millimeters I'll add in my sketch fillets make them equal and they are two millimeters uh one millimeter okay I'll bring back in the pad double check it looks like it's centered yes close that pad that symmetric 19 click ok all right that's looking like it's pretty much done but we're we're not quite done yet so like I said we we've got this retaining feature in here to prevent the part from wiggling back and forth and so we need to create a retaining or a mating feature I'll just hide that inside here so it's essentially just going to be a Raceway we can do that pretty easily by sketching on this plane here um we'll hide that we're going to do two little rectangles on either side to create our Channel and let's make these symmetric of course will make their distance between each other 4.3 so if you remember that inner leg is four millimeters wide so we're just having a very tight 0.3 millimeter clearance total now let's make these equal and then these legs equal I'm actually going to remove these vertical constraints here if it'll let me because I want to have a little chamfer on there and I'd rather do it as a sketch than as a feature it's also going to help with 3D printing I'll show you what the orientation will be in a minute so I'm going to go over to my constraint panel to find those constraints all right uh let's make these this could be like 60 um 120. so that'll be a 60 degrees I'll make those symmetric uh the overall height needs to be 0.3 millimeters um I know that the the inner legs were 0.5 but I don't want this to be I'm trying to reduce the friction I guess is what I'm trying to say between the parts you know you just need something for those legs to bump across and there's not much else for them to go so there's like no chance of them slipping underneath here and uh yeah so 0.3 is I found was sufficient to do what I needed it to do let's make this leg 3.5 millimeters wide so then we'll just need to um I think making these legs equal should be enough to lock it in place oh right uh from the top to this axis is 6.5 bring back in the pad just double check left yep that looks perfect now I know I skipped through a lot of these dimensions all right I know I go through these Dimensions fairly quickly I don't always explain where they where they're coming from so as I'm building this model and I'm deciding what features to put in here you know I don't know exactly what they're Dimension is going to be I just know I want it first like for example to be attached to this surface here so when I get around to modeling this part of it I'll close it out I'll go back into the previous sketch to see where that uh Dimension is and then I'll come back to the sketch and plug it in um close that that's done okay that looks good now what I'm going to do is I'm going to pad that in the reverse Direction and looks like I have 21.5 as the overall length for that so that looks perfect and now like I said I plan on 3D printing the part in this orientation and that's because uh when it comes to printing without support material your 3D printer can do a certain amount of bridging you'll want to test what your what your printer what your settings are capable of handling but without worrying about it too much you know this distance is pretty small it's six millimeters so that's like a quarter inch um and so printing it this way ensures that I can have some bridging and I don't have to worry about uh severe drooping or anything like that if I try to print it in its modeled orientation that's a pretty sizable Gap and there's also a little feature in here that just will not print so you'd have to have support material and I don't have um soluble support material and Breakaway support material would just be a nightmare it it'll make the part useless so um you got to model it this way okay I've been rambling way too much in this video I apologize for that so uh we just need to mirror this um so the part is design the male part is designed uh you know to print on this surface so there's only one retaining feature you know I can't do it on this side as well um but the female part because of the way I'm printing it I can actually put those on both sides and that would actually be good that that's a good way to design this part because the male part could go in in either way it could go in in this orientation it could be flipped and go in as well and I want it to clip securely in either in either situation so I'm going to hide the male part again I'm going to create a datum plane for this I need to create a plane so I'm going to click the X Y plane which is the top plane and I'm just going to make it uh three millimeters above that click OK on that I usually like to after I create a datum plane I really like to move it to the beginning of the body so that I don't lose it and also because it's not referencing anything in the body um so it can be moved there and it makes the bottle more stable so we'll take this pad I think I could just pick symmetric and then I'll add my selected reference which is that plane and there you go let's hide that don't need to see that and that's it you're done that is a fully modeled snap clip um let's just move this male port mail part out so you take negative 35 I think is about what works okay so that is how you model and design a snap clip for 3D printing in freecad so we went through modeling the mail part taking note of some of the design features such as how thick this wall should be how long this leg should be what the space between this point and this point should be and all of that to create a functioning and reliable clip thanks for watching this video I hope this was informative and interesting for you let me know what you thought in the comments please leave a like if you liked the video again thanks for watching and I will see you in the next one [Music] foreign [Music] [Music]

Channel: KTEC DESIGNS

Views: 9,550

Keywords: 3D Modeling, FreeCAD, 3D Printing

Id: v-Wo-BD66DE

Length: 46min 33sec (2793 seconds)

Published: Wed Feb 01 2023