FreeCAD for Beginners #2 - Sketching and Constraints

[Music] well timing is everything so i released the first in this series for absolute beginners showing you the download and how to run free care for the first time create sketch and produce a model of course on the same day that i've released that video free cad released version 0.19.1 as the stable release so i'm going to show you how to download that so all we need to do is to go to www.freecadweb.org and we're going to say download now and we're just going to download the version that we want so i want the 64-bit window version and i'm going to save this file and it's an installer so i'm going to save that and i'm going to actually install the latest version of freecad now you can install the app image for linux and i do have one of my subscribers has said that the ppa version for ubuntu is actually easier to use it's entirely up to you if you want to do the app image or you want to do the ppa version you can certainly check that out just want to check this free cad release page see what the new release is yeah there's no there's no development release at the moment so it has just become the stable version how exciting so after downloading the freecad stable release i'm just running it i'm gonna see if it actually replaces the stable release that i have installed um here we go so it's 0.19.1 it's the freecad license i'm going to accept everything there and i'm going to install for anyone using this computer and i'm going to put it in that freecad 0.19 file and i'm going to allow it to associate everything with freecad with this guy i'm going to create a shortcut i'm just going to allow it to install so it doesn't look like it has uninstalled the other version that i have installed i've been using the development versions for a long time and those you just click on the executable so they are pretty much standalone i'm going to clean up and get rid of all my development versions and use this stable version from now forwards okay so let's run freecad 0.19.1 the stable release for the first time and let's see what we get as far as the um startup is concerned that's a new splash screen that they've created for this version but i expect the interface should look exactly the same as i have been using as i've been using the development version right up to this point so i was on pretty much the latest development version so there is the interface and with mine it starts up directly in part design yours may start up in that start screen that we talked about in the last video so if yours starts off in a screen that looks similar to uh the one i'm about to show you then to follow along so here's what you may be seeing something like this to follow along just go to start and select part design so we'll just select part design here and today in this video we're going to cover creating a sketch and we're going to create that sketch from a a rough sketch i made on a pad that shows the dimensions so here's the rough sketch that i made and that will show you the dimensions that we want to uh create so here in part design i'm going to start a new file and i'm gonna save that file first thing to do is save the file so i'm gonna save that file and i'm gonna save it as second file because i already saved a first file looks like my assembly two workbench is causing an error i have assembly two installed and apparently it can't find an icon so i'm gonna ignore that error so now i've created a part or a file i'm gonna create a part in that file so i'm going to use this create a new part and make it active then i'm going to create a body and make that active and now we're ready to create a sketch if we go to our tasks over here so this is a tabbed interface tasks the next task on here create a sketch i can click this one or i can go here and create a sketch now one thing to note is when you create a sketch freecad will automatically switch this part design to the sketcher workbench so let me show you that here's a sketch i'm going to pick it on the x y plane now you've got two options here you can if i just rotate this around all i'm doing is pressing my middle mouse that lets me rotate it around a little bit like that i can select the xy plane from here so if i select that plane you see it selected it over there so i can select that plane so if i wanted to do it in a different plane it's easy for me to see this plane or this plane but i know i want it in the x y plane so i can also select it from here and that's what i'm going to do and select the x y plane and i'm going to say ok when i do that as i said it switched us into the sketcher workbench the sketcher workbench has all these tools in it so these are the tools that you need for sketching and what you should see is the center point of your drawing space so i tend to use that as the center of everything so i use that as a center point you can use as the bottom left point the top right point whatever you want to do i tend to use it as the center point now if you want to scroll in or sorry zoom in zoom out it's just the scroll wheel the middle wheel i'm just scrolling that up and scrolling it down if i want to move it over because i want this center point to be up here somewhere i press shift click that center and it allows me to move it so it's a good idea to get used to that because sometimes your drawing is over here in the corner and you actually want it in the middle and you want to be able to shift around in it so zoom out with the scroll wheel hold down shift click the scroll wheel move it around to where you want it and then zoom in now looking at my picture i have a fish shape i'm going to call it a fish that i drew it's an arbitrary part i drew just for some interest and i wanted to show you how i would go about sketching this part now i drew it three-dimensionally i sketched it three-dimensionally because that's typically what i do when i i'm designing or creating a part i'll sketch it three dimensionally so i can see what it is i'm actually creating um but of course you're going to draw the 2d outline so the first thing we're going to do is we're going to select our polyline tool and we're going to create that shape now i'm not going to worry about the dimensions right now i'm just going to create the shape something that looks like it so i'm going to click on this polyline i'm going to pick a line i know it goes this way i know it goes here i know there's a piece that goes out here down here back here down across down all the way back to here up to here out here up here down here and back to that line there and then i also know i have a square somewhere here so that's the rough shape i didn't look at any dimensions i just went with a rough shape now what i like to do is i like to start the constraining of my sketch using geometry first so by that i mean things that are horizontal or vertical or at a certain angle or attached to certain lines now what we want to do is we want to make sure that we are dimensioning the important parts when we start dimensioning we want the important parts dimensioned and so we're going to use the sketch as a guide because i've dimensioned the parts that i want to be a certain size and then we'll allow the other pieces to be the size that they are from a you know calculation standpoint now one thing i wanted to show you if we zoom in here a little bit you can see these constraints this constraint is saying this line has to be vertical so if i try to move it you see the line moves vertically it won't allow me to shift those points in different places they are vertical so they have to remain vertical whereas this line here you can see it didn't get a constraint for horizontal so this line got a constraint for horizontal so if i move that line it's going to move the whole line if i move this one i can shift the points around because it's not horizontal but on our sketch it should be horizontal so i'm gonna touch that line and go up here to the horizontal constraint and click that and now this line will move as a solid line because it is horizontal equally this line and this line don't have those horizontal or vertical constraints so this one should have a vertical constraint and this one should have a horizontal constraint and you see it automatically forces them to be horizontal or vertical depending on what we pick so those are all the simple ones and i can see from my sketch that this should be up here somewhere so it doesn't really matter where it is right now um it's where it's going to be when we finish up so again from a from a an alignment standpoint one of the things i notice is that this line and this line they should be aligned so i'm going to select that point and that point i'm going to put a vertical constraint and now those two points those lines are actually a line so it's going to keep them in in sync and then this guy and this guy are supposed to be in line so again i select the point select the second point and say vertical and now those are going to be in line so we've got some sloppiness we can we can move this around in certain places but we're starting to get it together if i look at this one so this point and this point they should be aligned so now we have multiple alignments that are in the right spot and we can look for things like symmetry or angular alignments tangential alignments we can check if our sketch is constrained if it's sitting together by moving it like this if these points were not attached it would move separately so you can see all my points are actually attached to each other so nothing is coming loose which is a good thing that's the advantage of using a polyline now if i zoom in on this part here if you watch this guy this point i can't move off this line and that's because of this constraint here so there is a constraint and let me just show you if we go down here we can see all the constraints in this model and if i click on that one which has that same symbol which is this constraint here which is a fixed point onto an object so this has fixed this point onto the x-axis that line there is actually the x-axis it's a little hard to see it with the grid over top of it but it's actually a red line and that line has this point affixed to it so i can highlight that point and say delete now i've deleted that constraint i can take that point and i can move it off that line so if your points get stuck on a line it's typically there's a constraint that's holding it there and so remember that if you if you want to move it off there you certainly can't do that now what we could do when i look at my sketch is we could make this point and this point symmetrical around the x-axis if that made sense but in fact i think my point might be better or my symmetry might be better somewhere further up from the dimensions that we have so let's take a look at saying up other geometry here um we have these are angles they should be the same so i can click that line click that line and tell them that they are equal and now those lines are the same so if i change things those lines should change in the same manner now what we're going to want to do is we're going to want to set up a center line between here and here or we can move the whole model down so that it it all centers here and to do that we have to be a little bit careful that we don't cause symmetry here to pull everything down and destroy our geometry if it turns the geometry inside out and you're basically going to end up redoing your geometry so so the best thing to do would be to pull down my geometry and get it roughly where i want it in terms of being symmetrical around those points and then i can say this point and this point around this line are going to be symmetrical then i can say this point and this point around this line are going to be symmetrical and then i can move this down to somewhere close i have this symmetrical and i have this part symmetrical i could make symmetry this way around that center line so that might work i'll do that and then click that point symmetry so now i have a symmetrical box that is around this line and let me just move those down because they don't want to be up there they're going to be down here somewhere i do believe and we have the shape constrained from a geometry standpoint so what we're going to do now is we're going to start adding some dimensions so we're going to do a horizontal dimension we're going to tell it this piece here and we know that needs to be 80. so i'm going to make it 80. now remember i made this and this symmetrical to this line so it opens up equally across that line i also know that this should be 50 as that is what i had selected so if i make that 50 and i also have a dimension a horizontal dimension between here and here of 20 and remember now this is symmetrical so it's going to open up symmetrically um this this part here is held because these two lines are equal so it won't go up and down it will go in and out though so we will need to apply a horizontal dimension between here and here of 20 and now you can see that this has changed color and it changes color because it's basically this this feature is constrained constrained means if i try and move it it shouldn't move anymore it now knows where it lives in relation to a fixed point um one other thing i should show you is if you highlight these dimensions so if i just scroll over i just roll my mouse over top of this until it turns yellow i click it then i can move it and you can move these dimensions around it's not this is not a technical drawing so it doesn't really matter where they are it's so that you can see them and that you can read the dimensions so again it's it's a good idea to keep the dimensions tidy so as far as other dimensions are concerned i can do a horizontal dimension this way i know that should be 40. and i'm gonna just grab this line here get to the line underneath i just wanted to grab the line so they can get ridiculously thin and i know that the dimension between here and here vertical dimension there that should be 80 as well and i'm going to scroll that back there so i've started to constrain the shape and i have a dimension for this horizontal piece it should be 30. remember these are these are vertically constrained so it's gonna it's gonna move both of them together because of that vertical constraint that we built in there so i'm just gonna move this dimension up to here just again just so it's neat when you zoom in and out the dimensions all get messed up anyway so don't spend too much time um place in your dimensions and then i know this guy from my sketch again is 10. let's bring that one out here and i know from my sketch again that this guy here is also 10. oh that's not true it is actually 20 so i'll show you how to how you edit a dimension so you highlight it till it's yellow double click it and then i can change it to what i need it to be so it is 20 and then if i go to the top here it tells me how many degrees of freedom there are in this sketch so if i look at this outside shape i'm just going to click on this line and try and move it i can tell this sketch is is constrained except for this guy that's still in white in the middle so first thing i need to do is i need to dimension this square and this square is a 10 by 10 square so as it's going to be square i can say this line and this line are equal and then i can dimension this line as 10. and drop him down there and because i said this line and this line are equal and it has vertical and horizontal constraints that's all you need to to lock that square in the reason it's still free is because it's floating in this area so i've provided dimensions here from here to here that's going to be five and from here to here with a vertical dimension that's also going to be five and now you saw that the sketch suddenly went green bright green that basically means it's fully constrained it says here's a fully constrained sketch that means if i grab this and try and move it it won't move because everything is constrained so we've told this sketch how to place these lines in a way that they can't be moved so it's a fully constrained sketch if you notice all i did was go through it methodically took my time kept the shape about the shape i wanted and created that now of course in my sketch it's 10 millimeters thick so we're going to close the sketch and then we're going to pad the sketch and it automatically goes to 10 millimeters thick and we say okay and now we have a model of that part fully constrained that is 10 millimeters thick leave a comment below if there's something you want me to cover specifically from a beginner standpoint please consider taking a look at our affiliate links below that helps a channel i'm gonna do uh a few in the series here obviously the sketching and the constraints are something you need to get to grips with but we're gonna do some models next time and show you how to do something so it's not all in a two-dimensional plane and then just extruded we'll add some features so thanks for watching please like this video give it a thumbs up and hit the subscribe button make sure you hit the notification bell we're expecting to deliver new videos every week so typically try to get them out on saturdays

Channel: Adventures in creation

Views: 30,121

Keywords: FreeCAD, CNC, CAD, CAM, CNC routing, Design, DIY, woodworking, 3D printing, maker, creativity, art, crafts

Id: M_lDwWaB4Jc

Length: 25min 28sec (1528 seconds)

Published: Sat Mar 27 2021