FreeCAD Beginner Tutorial #2

in this freead tutorial we'll be modeling the following object using the part design workbench I'll be referencing this image uh for the dimensions throughout this project so I'll include a link to this if you'd like to download it for yourself so to begin I'll go ahead and just create a new project in freecad make sure I'm in the part design workbench and I'll create a new body followed by a new sketch I'm going to be starting this model by uh creating this top down view in my 2D sketch so I'm going to choose the XY plane and now that we're here in the Sketcher uh workbench I'll create a rectangle for the base of this object however instead of the regular rectangle sketch tool I'll do the centered rectangle that way I can position it on our origin here and drag it out so it's symmetrical I'll go ahead and give it a 40 mimer vertical distance constraint on this uh line here 40 mm and for the horizontal distance I'll give it a 70 mm constraint so we'll give that a 70 MIM distance cool and I'll go ahead and create this circle uh while we're while we're creating this view so I'll come here our Circle and we can see from the diagram that is a 10 mm diameter so I'll give it a diameter constraint of 10 mm now for the positioning of the circle we can see that the center point is 15 millim away from the bottom right corner of our Square on both the horizontal and vertical axis so I'll select my Center Point select the bottom right corner then I will give it a horizontal distance constraint of 10 mm now I will select the Center Point again select the bottom right corner Center Point bottom right corner and then we'll give it a vertical distance constraint you can see here our sketch has turned orange which means we have some redundant constraints so if I were to try to create a 10 mm constraint here and click okay you can see that nothing really happened the reason is we have this uh constrain point on object constraint and this was autocreated when I created this circle you'll notice when I had made it I place my mouse cursor over the uh xaxis on our sketch and you can see the icon for that constraint shows up next to my circle tool so we actually don't need that tool or that constraint so I can select it and hit delete and now we have the freedom to move this circle up and down so now if we create or if we select the center point then select the bottom right now we can apply this vertical distance constraint of 10 millim drag these out just to kind of clean up our view here and we can reference our sketch and actually I was creating 10 millimet I was supposed to be doing 15 so let's fix that 15 and 15 now if we reference our sketch from our top down view here we are looking pretty good so I will go ahead and close this sketch and I will tasks and hit pad and of course you can also access the same tool from this location here click pad and the default pad length is 10 millimet and if we refer to our diagram here we can see that 10 mm is the correct depth so I'll go and hit okay all right so this bottom portion is done now I'm going to go ahead and um Target this top portion of the sketch here or the model so to do that I'm going to select this face and create a sketch uh using this as kind of our our sketch origin so I'll click this face here and then create sketch and I'm going to need to reference this line to create our uh to create this kind of top portion on so I will add some external geometry click this line here and now we have this reference line to build on top of so I use the polyline tool to kind of sketch out these lines that make up this sort of U shape so I'll start at the bottom left and again notice over your your mouse cursor There's a constraint icon so that is a coincident constraint which is what we want I'll bring that up I'm just going to kind of build a rough rough outline of this shape and I'll bring it all the way down and again um I will create the vertical uh constraint the little line you see there as well as the point on object constraint okay you can right click to get out of that that line selection tool on the poly line right click again so now we'll want to go ahead and Define some dimension on these lines that we created uh we can see on the left here that we have a total height of 40 mm from the top of that line uh to the bottom of the pad we had already created we know that this pad is 10 millim in height or depth so that means this line will need to be 30 mm total to 40 uh so I'll actually use the vertical distance constraint give it a 30 mm distance um if we reference the sketch we can see that uh the shape is pretty symmetrical so this line here will'll need to match up this line here so I will select line we just created this line and I will use an equality constraint so now this line um inherits the kind of properties of this line since we had already defined a vertical distance constraint of 30 mm this one is also constrained to that um now we will go ahead and create this top portion so we've got a distance of 10 mm here select that give it a horizontal distance constraint of 10 millimeters now again we could either just manually create it on the other line or we can use that equality constraint select both of these hit equal okay we're good there now if we reference this other value we've got a vertical distance of 20 millimeters for this line here so I'll go ahead and do that say vertical constraint 20 millim cool and once again I will go ahead and just create an equality constraint so that these two match up okay now uh fread has highlighted our sketch green and it says it's fully constrained so at this point it's looking like we're we're good to go um but if we go ahead and close out of the sketch and then try to Pat it we'll see that it throws an error um recompute failed well we can click okay get out of here wire is not closed so what that error message is telling us is we didn't close the sketch we had created so if I come over here into the uh model view select our pad and hit space bar it'll actually hide the pad and we can see the sketch we just created and of course it's obvious now that we are missing this bottom line uh to fully close this sketch show that again so if we double click on sketch we can come back here and now what we can do is use the line tool and go from our bottom left point to our bottom right point and now you'll see that we have a redundant constraint here and the reason why is when freecad is doing these Auto constraints for us as you may have noticed you know once I Mouse over here it shows that coincident constraint once I Mouse over this one we have both a coincident constraint and a uh horizontal line constraint well we also have this point on what is it point on object constraint so basically we don't need that anymore I can just go ahead and select that and hit delete um you'll see we lost uh lost some of our constraints here so let's see what's going on okay so if we grab our sketch here and drag it around we can see where we are under constrained and in this case it's on the horizontal axis here um so I'm just going to select this bottom line and create a horizontal distance constraint and give it 40 millim hit okay and now we are fully constrained so we can close out of this sketch and we can come back to tasks and Pad once again and you'll notice again um that pad didn't seem to work if we were to hit okay gives us a warning message saying results has multiple solids that is not currently supported well if you click reversed you'll see that now our our object is is showing up so what's happening here is before we had reversed this pad it was trying to pad the the object out away from our away from our object our existing object so if you imagine this going in the uh opposite direction as to where we're currently U extruding our pad and basically what's happening is because we have a distance of zero uh between between these points here freead is not recognizing that as one single object um and so when we were to when we were trying to extrude the opposite direction it was recognizing it as two objects which as our error message stated not currently supported by freead so we'll just reverse that and then we're good to go so of course we want uh this portion to extend all the way across the length of our pad here so you could just increase the value here to make that happen or my preferred method is changing the type from Dimension and selecting up to face and then you can just click on this face back here and it will kind of extrude that sketch all the way across to the face that you had selected okay so we can click okay I'm going to close out this report view just so it's not filling up our screen and now we can go ahead and create this angled cut that we have here so to do that I'm going to select this face of the object and create another sketch so I will select this face we're going to be creating a sketch and this is pretty similar to what we just did except in this case instead of padding our sketch we're going to use the pocket tool so once again I'll need some external geometry here I'll select this Top Line and I'll select this bottom line so if we look at our sketch we can basically see that we need to cut out kind of a triangle shape here so to do that I'm going to create a point and place it on this Top Line again being mindful of the constraint that it's autoc creating and we can see here that we need a total length of 20 millim on this top face um remaining after we do this cut so what I'll do is I'll select the point I just created and then I'll select this top right point and I will create a horizontal distance constraint of 20 mm cool so that's spaced properly but now we need to uh complete this triangle shape in order for us to do the cut so I'll just use the line tool here I'll start from the point we just made go all the way to our leftmost uh reference point create that line and I'll create another line from that point to this point and then finally we will create our last line connecting the three points and that we have our triangle so we can close out of here come into tasks and we can do the pocket tool so we'll pocket that and once again if you prefer to you could increase your length manually or just change your type to up to face and then select the face you would like to cut tool or pocket to okay you can click okay and oops now we just need to complete this last feature of our of our object here so once again I will select an existing face of ours to build our sketch upon I'm going to select this one back here we will create sketch and if we refer to our drawing here we can see that uh this back wall needs to be 20 mm High so I will create a reference geometry of this bottom line here and I'll go ahead and create the reference line for this point as well I'll use the rectangle tool um I don't necessarily need a centered rectangle so I'll just use a normal rectangle and I'm going to just kind of create it out here floating in free space for a little bit uh just to kind of take a different approach when I'm creating this so I'm going to um Define my constraint for the 20 mimer vertical distance here so we'll do 20 millimeters and instead of hard coding any sort of um horizontal distance because I don't think the sketch really tells us exactly how long it is um but what we do know is that our bottom corner meets here so I will take this point and use the coincident constraint and join it to this point oops click that again okay um and now we can see that our length of this object is a little bit long so once again I will just take our Point here coincident and select oops select these two points and then give it a coincident constraint okay so now we're fully constrained and you can see that we need to create a fillet in this design here so there's couple different ways you can go about doing that one is creating the fillet here in our sketch and that would work pretty well or if we close out of here we can pad and once again see how it's gone blank and if we okay multiple solids well again it's trying to pad that object away from our existing object so if we reverse it let me close this here if we click this reverse button it will change the direction in which we're padding and so now freeads happy we'll Pat at 10 millimet because that is the uh thickness of that wall hit okay and at this point we could select this line and then simply use the fillet tool in the part design workbench and we can ramp that up to our specified 20 mm can either manually just click all the way up or you can just type in the value you want and you'll notice something that if you if you try to give it a 20 M 20 mm radius and hit okay gives you an input error fail to create fillet uh basically what's going on here is uh the freead fillet tool is very sensitive about lines um kind of overlapping or joining each other basically so if we were to reduce this fillet value to 19 millimeters you can see that these two lines are not completely touching and freak ad's happy we could even bump it up to 19.99 hit okay and then if you zoom in and you can see they're still not touching so free cat's happy but the second you try to make those exactly 20 mm where those lines would then be joining fread has an issue with that so depending on the nature of your design you know if you just kind of need a quick and dirty solution 19.99 that may be plenty of precision for your part um but if you'd like to go about it in a different way we can create that fillet in our sketch so if you need to go back and modif I um a sketch after you've already padded it you can select the pad from the model view hit the drop- down arrow and then double click your sketch and then we're back in the sketch view now we can use the fill it tool to create our fillet in our sketch view here so I'll just select this tool and then select the two lines which I'd like to create a fill it between and you'll notice a few things happen so first off we lost our uh vertical constraint that we had created previously so we'll need to address that and it's created these tangental constraints uh between the lines and the uh Arc that was created and you'll notice we have this line portion that's between um our bottom point and our Arc uh for our particular uh model here you can see that there's actually no need to have a vertical line um between this point in the arc so that may actually cause some issues for us having this line here so I'm going to go ahead and select it and then just hit delete and you'll see it's remove that tangental constraint for the bottom point of our Arc um so what we can do now is just select this point and then select the point we will need it to be joining to and then use the coincident constraint now our Arc of course it's uh looking a little off now so we can just give it a uh diameter constraint of 40 mm and it's looking better but we still need to add that vertical distance constraint that we had initially lost I'll select this line and give it 20 mm okay we're fully constrained we can hit close and our uh pad has already updated close out this old report View and now you can see our uh model was completed um let's see you'll notice how we're still currently seeing uh this sketch here because I had selected it and pressed space bar at one point so typically you wouldn't be seeing the highlight of the sketch so I can hide that okay well that completes this tutorial uh thanks for following along I hope you found it useful uh feel free to leave any questions in the comments thanks bye

Channel: JeffCAD

Views: 2,512

Keywords: JeffCAD, FreeCAD, Tutorial

Id: VZ16lty5ADg

Length: 19min 57sec (1197 seconds)

Published: Fri Mar 08 2024