FreeCAD for Beginners | Design a Marble Maze

hi there this is irv shapiro with the dr vaxx channel and today i'm going to teach you how to build what might be the most complex model i've ever created no it's not a replacement part for my automobile no it's not an elaborate new mechanical device it's a toy and in fact it's a very simple toy it's a marble maze where the goal is to manipulate the marble into the center now what's interesting about this design that i'm going to produce in pre free cad is it's almost completely parametrically driven you can go into the design and enter a new value for the size of the marble and the design will properly scale in order to do that i need to teach you some more about using spreadsheets in freecad some additional types of constraints about how to position sketches on a plane not at the origin and why when sketching centering your model around the origin and tying dimensions to the origin will make your life easier so if you're interested in creating fun new toys then stay tuned and let's learn something together now i'm going to take my glasses off so i can see the computer a bit more clearly but before we continue with the lesson i want to urge you to subscribe to the channel because that helps me out with youtube in addition i need to give a shout out to one of the drvax.forum.com users a very active user that goes by the name of g-e-i-t which is his nickname i believe it's pronounced geit it's a german nickname that comes from the german word for guide and guit showed me some very interesting techniques when i uploaded an early version of this model and really pushed me to include a bit more material in this video so i'd like to give him a shout out now if you don't know what forum.drvax.com is it's a user community of about a thousand really helpful and kind people that help each other out with various maker challenges really remarkable group of people it's completely free provided as part of the benefit of the dr vaxx community which is once again why subscribing helps us out because when you subscribe youtube will show more of my videos which helps me support pay for hosting of things like forum.drvax.com if we look here on the screen i'm going to start by doing something i do at the beginning of each video because it helps my users out a lot i'm using 0.19 the .19 version of freecad but every version of freecad looks a little bit different when you first load it up depending on the version and on your computer so the first thing i always do is arrange my toolbars so i can see the things that are most important to me so i'm going to go here and select the part design workbench now another important point this shouldn't be your first free cat video there's a whole series of videos that i've linked up above on this channel that will help you get started in freecad so i'm going to rearrange my toolbars by going to the thicker dots you'll see they're thinner dots might be hard to see in the video and thicker dots where there are thicker dots you can drag a toolbar around now once again if i was back on the start workbench a workbench being a collection of tools you won't see all the icons so i need to go to the part design workbench and then i want to make sure all of these icons are visible and these icons right here are part of the part design workbench i'll create a new document by clicking here then i'll create a body this is all old stuff the people that have been using freecad for a long time i'll create a sketch on my xy on this plane but before i start modeling i want to do something a little different i want to define all of the critical positions in this toy what's the size of the marble what's the size of the hole that the marble will fall through how far apart are these walls what this what's the thickness of the walls and in fact all of these dimensions are tied to the size of the marble if i use a ball bearing instead of a marble or maybe a bb i want these to be closer together now there are a couple different places you could store these values these parameters i like to use a spreadsheet so to create a spreadsheet i'm going to close this model go back to the model tab and up here i'm going to select the spreadsheet workbench click on this icon to create a new spreadsheet now i'm going to double click in there and you'll see the spreadsheet here so the first thing we need is we need the ball size okay well mine is 15 millimeters okay simple enough in order to use a cell from a spreadsheet in your model you need to right click on that cell go to properties and create an alias so we'll call this ball diameter because 15 millimeters is the diameter not the radius now when you define circles or spheres or other shapes the round shapes in freecad you can define them based on a radius or based on a diameter we're going to use a diameter right now now i need some space on the sides of this ball so that it will work its way around properly so i'm going to set that space as the ball gap and we're going to make that 2.5 millimeters once again i'm going to define an alias and we'll call that ball [Music] gap now i need to start defining the actual geometry of the toy so we have this first center wall and so we're going to call that center wall so we'll make that 30 millimeters now that's going to be the inside of this wall then we'll need a width to get to the outside so we'll need a wall with and we'll make the wall with two millimeters once again we need to define aliases now we need to define this space here how big is the track so we're going to call that track width and let's think about that for a moment it's the size of the ball the size of the gap so we're going to define that using a formula in here we can actually type the aliases we've already defined so we have the ball diameter plus the ball gap so that's going to be 17.5 properties here and we're going to call that track with so now we can go ahead and define the positions of the other walls so we could call this wall one and wall one once again is going to be a formula and that's going to be from the center wall plus one wall width because the center wall dimension is the inside of this edge not the outside plus wall with plus track width let me bring up a version of the spreadsheet that i've already produced so file open and let's see here we'll bring up this one and let's look at the spreadsheet here so we have the ball diameter and if i miles over these it will actually give me the name we have the center wall the ball gap the hole size we're going to need to know how large we want these holes to be so the ball will fill through fall through and that's going to be about the size of the track width maybe slightly smaller we're going to need a height for the wall so the wall height well with we can see here the track diameter and then each of the additional wall positions now let's look at one of these formulas so we have the center wall plus the track diameter and in this case the track diameter i included all both the ball the gap and the wall width now why is it multiplied by two well because i'm going to define these circles using diameters not radius and the width of the track if we look at one width here that's only on one side you have the same width on the other side so you have to add those together in order to get the correct value what are these numbers down here well if we look at one of these we'll see it's the center wall plus track diameter this one is wall one plus the track diameter wall 2 plus the track diameter etc and i wanted to make sure that they're all the same that i didn't have an arithmetic error so i created a check variable i subtracted one wall from the next one to make sure the sizing is all the same now let's go back and start drawing our model so i'm going to create a body create a sketch put it on the x y on the flat plane and you'll see here the origin this is really important i'm going to do all of my modeling around the origin and you'll see later that'll make constraints very easy so we're going to start by putting defining the first wall so that is the inside of the wall now we'll go back to the origin again and that's the outside of the wall and now let's dimension these so i'm going to go to the constraint for a circle and i'm going to select constrained diameter and here i'm not going to type in a value i'm going to click on the fx and i'm going to say spreadsheet i can just select that dot center wall okay okay and you can see we have our 20 millimeter and we can move this dimension around by just clicking on it 20 millimeter inside wall so how big is this one well let's dimension that one now constrain the diameter click on the fx spreadsheet dot center wall plus spreadsheet click it here dot wall with okay okay and now we have our first two walls defined right here so i could come out of this right now i could close this model it's fully constrained i could say pad and on the pad instead of manually typing a value i could click on fx and i could say spreadsheet dot wall height okay okay and we have the center structure now i don't have the connecting bridge i don't have the gap yet but we'll get there now because this is a parametric modeling environment i can always go back and continue to add to my sketch so i double clicked on the sketch here and now we're going to add some more walls so it's as easy as selecting the wall tool selecting the next one there selecting the wall tool going from the origin selecting the next one there that's the second one okay now let's take a look at all of the concentric circles we've created and understand the purposes of these connecting walls are they there just to make the game more interesting or are they a requirement of a successful model let's see so if we return to the screen we'll see we have our circles here i'm going to select an edge of the model i'm going to go to tasks there we go i'm going to go to tasks and create and click on pad and attempt to pad this model and i receive an error what's the cause of this air failed to validate broken face in free cad when you have a sketch all of the lines need to touch another line the sketch has to be contiguous in essence or enclosed within a contiguous area so when you then go to pad if your pad is going to create multiple bodies multiple separate parts it's going to fail the error message will depend on the specific sketch but in this case our concentric circles two circles would work that'll create a cylinder but you cannot create a cylinder within a cylinder that's two separate bodies so let's fix this i'm going to cancel this pad i'm going to go back to the model double click on the sketch and you can see here i have a sketch with all of the circles and all of the dimensions if we look at one of these dimensions and click on fx you'll see here it's using the spreadsheet the wall four plus wall width etc now how do i connect these together well the way i'm going to connect these together is by adding these internal sort of walls or bridges so i'm going to do is click on the line segment tool then click on a edge of one of the circles click on an edge of the second circle then i'm going to do that a second time one of the circles edge of the second circle now these are not constrained at all and i'm going to want to make them a certain width so how do i do that well the first thing i'm going to do is i'm going to click on both of these line segments and i'm going to add a parallel constraint so now they will remain parallel one to the other before i move them closer together while they're still far apart i need to remove the segments of the circles inside those bridges so to speak so there's a tool up here it's called the trim tool trim and edge with respect to the pick position you can see that also if you go to sketch geometries trim edge so i'm going to select that tool and now i'm going to click on this edge and this edge and then right click to deselect the tool let me zoom in so you can see that so now you can see that the inside circle has been removed what i've in essence done is create one of these bridges but this in this model i printed here these are different sizes let's make them all same size so i'm going to take and use a constraint that we haven't used before two of the constraints that we use very often are horizontal distance and vertical distance but you also have a constraint which is just an absolute distance between two points or two lines select this point command or control in the case of windows select this point and now how far apart do i want those well this is just a wall so let's click on fx spreadsheet dot wall with okay okay and now i'll right click to dismiss that tool pull this out and we'll see that's now two millimeters now i need to do this for each of these individual circles so let me do one more just to give you the idea so i'm going to do this a little quicker here we'll do this edge and oops that edge there and this edge and that edge there we're going to make them parallel we're going to use the trim tool to remove the inside there we go there and there let me click on this point here whoops this point here and command in this point here and add a dimension to it and i'm going to make that spreadsheet dot wall with ok ok and now i can move this around anywhere i want on here and we can make them perpendicular and we could put additional constraints in to constrain that these are perpendicular and that they're a particular place on the rotation and i'll show you an example that as we start putting holes in walls because the same technique would apply but for right now we'll leave that as that and i have one that we can open up that has all of the walls already defined in it and you'll notice that this one is extruded this one is padded because the pad will work successfully now because this is a completely contained sketch which only creates one body it's a single body because their place is touching everywhere in the body okay now that we have the walls i'm going to put a base on this now when you watch this you'll see that perhaps i should put the base on later when it's all finished it would make things a little easier but i'm going to put the base on now because i want to show you about attachment point about when you have a plane how you put a sketch somewhere higher above that plane and so let's put the base on first and then we're going to cut holes in the walls without cutting holes in the plane by using an attachment point so very simply here i'm going to go to this body i'm going to go to task i'm going to create a new sketch on the x y plane so that sketch is in essence on the bottom in essence underneath this diagram i'm going to have this sketch be a circle i'm going to give it a dimension and we're going to give it a dimension using a formula so that we can change it parametrically so spreadsheet dot wall four and uh let's ask add one millimeter so it's just a little bit outside the um existing dimension now you'll notice when i just added plus one there's a unit mismatch and that's because in the spreadsheet i've defined the units as millimeters so here i have to say one millimeter okay okay i can now close this i can go back to our model i can select this sketch but to see that i'm going to click on pad walls and hit the space bar to make that not visible so let's select this right here and we're going to go to tasks and we're going to do a pan and we'll make the base one millimeter should be enough okay this is starting to look like a maze but once again we need to now be able to get from this track to this track to this track how do we move from one to the other well you use a tool to cut an opening in the wall what is a tool it's just a shape we have a tool that's the right size that's the dimension of a hole to do this i need another sketch i need a sketch that basically i can use to create these new shapes that i'm going to use to cut out these openings so i'm going to click on the body i'm going to go to tasks create a sketch on the same base plane whoops i'm losing my marbles here on the same base plane so now we're underneath this let me go over here to model once again and turn off this pad but i'm going to turn on the wall sketch by selecting it and clicking space on it i'm going to make sure that sketch is on and now i can add some cutouts here so how do i add a cutout well i'm going to take and create a circle and we'll just put one right there and i could have let's say a cutout right there and a cutout right there so now the ball could go in here then in here then in here and now we need one more cutout and let's put it right there now how wide do we need these to be well we have that dimension already set because i can go here to constrain diameter and i can put in spreadsheet dot whole bang now i can also select this circle this one this one and this one and i can say they're all equal and now they're all dimensioned so let me go to tasks now and close those and i have those selected so let's select one of those edges of that one as an example go to tasks and create a pocket hmm i don't see anything here what's going on well let me try reversing it oh now creates a hole underneath so it seemed like it was okay but it's probably not the right dimension so we're going to make it spreadsheet dot wall height okay and now it is properly cutting out but it's also cutting out the bottom well we want the hole to be going up not down so we clicked on reversed and but it's too low so let's click ok for right now and see if we can figure out a way to move it up so let's go back to that sketch and you'll notice down here there's an area called attachment so it's attached to the x y plane it's right at the bottom we have the base also attached at the bottom extruded a millimeter up so it's cutting through the base so we need to move it above the base by one millimeter so we're gonna click on position z we'll move it one millimeter up click out of there and now you'll see it's no longer cutting through the bottom we can zoom in here and you'll see it's properly cutting out the walls using our circle but not cutting through the bottom okay now how do i go though and i define exactly where those circles are going to be because it's sort of important if i scale this thing up or down i don't want those moving around before i do that let me demonstrate this is actually parametric right now so i could go back to spreadsheet i could say the ball diameter is now 20 instead oops 20 millimeters so clearly that's bigger now and you'll notice that the center is not proport in any way defined by the wall so let's fix that so the center wall diameter is defined right now as the wall ball plus five millimeters okay so let's instead say it's the ball times 1.20 we'll make it 20 bigger than the ball we'll see if that works better so now let's go back to our model and that works a little bit better so now let's put this back at the ball diameter let's set it back to 15 millimeters return and there we're back at our original sketch so we have a parametric sketch here we have a sketch to where we can change parameters and the sketch will scale properly but what about the location of these guys because if i go here and i click here these guys um sort of can move all over so we need to do a couple things the first thing we need to do is position them in this direction these holes so i'm going to take and click here and click command here and put a dimension on that a length and once again we want to use a parameter spreadsheet that's wall center one two three dot wall three but we don't want it centered on the outside of the wall we want it centered on the spot halfway inside the wall width so we could make that plus spreadsheet dot wall width divided by two and that will position it exactly in the center of the wall so let's click ok whoops now why didn't that work well the wall dimensions are diameters diameter is the dimension across the full circle we want we're going from the origin not the opposite side so we have to divide by two in essence we want a radius so let me take this dimension here go back to our formula put this whole thing in parentheses and divide it by 2. there we go now this is staying locked in there it still can move around the arc what if we want to fix the position in the ark well we can do that also because we can define an angle so let's actually draw a line between this point and this circle here but let's actually extend it out here just to make it a little easier now how do i take this and i can strain it to this line well for that i use a fix a point onto an object this item here i don't use a tangent constraint that's a little different so we do that there and now that line is going to stay locked there and the length doesn't really matter so now i can define the angle between this line and this axis so i can click on this axis and this line and i can put an angle constraint on it let's make it 150. now i could put this in the spreadsheet i probably should for right now we'll just type a number in there we go so let's find that 150 here sometimes hard to see um and that you'll see it's 150 degrees from here to here and i could change that to let's say 30 and it moves it over there i could change it to 60 it'll move it up here somewhere let's actually make it over 90. so let's make it 100 and there we have it right there this circle the circle now is green why it's fully constrained so i can't move it in any direction but if i close this we'll see there's an air mark failed to create a face from a wire in a sketch wow these are really complicated error messages what that basically means is we broke our sketch because we have this line going off into the middle of nowhere and the pad operation doesn't know what to do with that so how can we fix that we'll go back to our sketch and we'll take this line that we used and let me move this over here so we can see it a little bit better we'll take this line that we're using for the purposes of just defining the angle and we're going to change it into a construction line a construction line is a line used for modeling purposes for dimension purposes but it doesn't affect the geometry so i'm going to select this line here and i'm going to go over here i always have trouble finding uh construction lines let's see which one it is here nope that's copy here we go toggle the toolbar or selected geometry to from construction mode now it's a construction line close and that pocket is now working properly so we've now fully dimensioned one of our openings and we could do that for all of our openings okay now let's go and put the holes in the bottom so that this puzzle is a little more exciting we want holes going through the bottom well to do that i'm going to click on body again i'm going to go to task i'm going to create a new sketch also on my x y plane and we know how to make holes already and this time we're not going to move the attachment point up we're going to leave it right where it is so let me go back to my model let me turn off this feature but i do want to leave on this feature because i want to know where those are so when i make my holes for things to fall through they're in reasonable places if i put them in the wrong places i might never be able to get between the walls so all we need to do here now is define some more holes we'll define one there and let's see here we'll define one here [Music] and maybe we'll define one here we have to think about this a little bit so the ball starts in this one it comes in this one it goes to this one it goes to this one okay when it goes to this one why don't we move this to down here and i'm going to move this one up to over here so it comes in here if you go the wrong way you're going to fall out and we'll move this one over here now how big should those be well we can dimension the circle using the whole dimension so let's take and click on one of those circles and do a diameter dimension and it's going to be spreadsheet that hole perfect and now we can dimension the distance from here just like we did before using the wall in this case we want to subtract half of the track size to get it in the right position for right now i'm just going to make these equal and do it by eye just so we can go ahead and finish up this model so we're going to make those equal and then i'm going to eyeball that a little bit there a little bit there that looks good so now we're going to close that sketch select one of the items in that sketch go to tasks do a pocket and make it reversed and we can see this one is over a little bit too far but you get the idea okay you can see here the final model this is almost 100 parametrically driven i can change the ball size and the maze will get bigger or smaller and if i take the time to dimension all of the angles that position the holes and the breaks in the wall then those will also stay in the same relative positions folks i hope you learned a lot here if you did give me a thumbs up recommend the channel and i really want to recommend you go to forum.drvax.com because there's an active discussion about this model on the forum there are almost a thousand people on that forum that are actively helping each other um and a couple thousand more people um participate by viewing the forum each month thanks again and let's continue to learn things together

Channel: Make With Tech (MakeWithTech)

Views: 22,669

Keywords: 3d modeling, 3d modeling for 3d printing, 3d modeling for beginners, 3d modeling software, 3d printing, 3d printing for beginners, free cad software download, freecad 0.19 tutorials for beginners, freecad 3d printing, freecad part design tutorial, freecad tutorial, freecad tutorials for beginners 0.18, freecad tutorials for beginners 2020, fusion 360 tutorial, pad and pocket, Freecad spreadsheets, freecad constraints tutorial, freecad tutorials for beginners, FreeCAD

Id: 0C4TjrTPCHY

Length: 40min 45sec (2445 seconds)

Published: Fri Feb 05 2021