FreeCAD for Beginners #5 Lofts and Sweeps

[Music] in this video we're going to look at lofts and sweeps and we're going to run through those in some detail first of all here's my freecad version so you can see i'm on the latest stable release i'm still on version 0.19 i've seen it listed as 0.19 0.19.1 or referred to as that in the builds however the revision number is that 24276 git so to create a loft we are first going to create the part um inside a new file i'm going to save that file save as i'm going to call it lofts and sweeps i already have a file called that so i'm going to select that save overwrite that file create a new part create a new body and then i'm going to create a new sketch inside that body on the xy plane say okay just going to create it with a square i'm going to now remember when you let me do that again i'm just gonna get rid of that square when you select that square if you look at my cursor i still have the square selected if i right click it switches off otherwise you can draw another square so we're going to select this point and this point and the center point and give it a symmetry constraint and we're going to select this line and this line tell it that they are equal and then we are going to dimension a line so i just have to put that down so i can get to my dimensions and dimension that line [Music] also got a little bit more space so dimension that line and now i have a fully constrained sketch and notice again i have the dimension tool is still attached to my cursor so i right click to get rid of that and i can just move that dimension outside here because i'd like my dimensions to be outside so i can see them then we're going to close that one we're going to draw another sketch inside this body so i'm going to take this sketch i'm going to rename it i'm going to call it first sketch now i'm going to create a second sketch again on the x y plane and the sketch has disappeared so to get that sketch back we can go into the model trees i selected the model tab into the model tree click on part hit the space bar and it'll bring our sketch back now i'll go back into my tasks so i can see my sketch here and i'm going to create another square just a smaller square and i'm not really worried about dimensioning these squares all i want to do is to demonstrate how to do a loft so selecting those points again i am using my symmetry select the side and the side make those equal and then i can select a dimension and once again a fully constrained sketch so now to create a loft we have to have an offset between these two sketches so what i'm going to do is i'm going to rename this sketch i'm going to call it second sketch and then what i'm going to do is select in second sketch i'm going to go down here to its attachment to where it hits z position so it's it's under you'll see it like this you can select that down arrow to attachment select the down arrow for position and then in the z or z direction i'm going to go 45 millimeters everything i do is in millimeters but if you work in inches it's the same theory just using different units so now if we want to do a loft and a loft is going to be a taper between those two there it's going to make a model of these two shapes so i'm going to first select my first sketch i'm going to use this loft symbol and it's going to ask me to add a section so i'm going to say add section select that second shape say ok and there is my loft so now i have a loft between two squares and of course you're wondering what would happen if that square was a circle or something else so let's try that we'll go back into our second sketch and to do that we just double click on second sketch down to the middle here and i'm going to draw a circle so i'm going to draw it from that point we'll make it just a little bit bigger then i'm going to delete the original square i've deleted that it looks like my circle is not quite on the origin so i'm going to select the origin select my center of my circle and use this constraint this is a coincident constraint i hit that it will line the two up then i'm going to constrain my dimension which is a diameter and be very careful with that i've showed it in other videos but the this symbol which is block constraint which blocks the selected edge from moving looks very similar to this constraint which is fix the diameter of a circle or dimension it so be aware that there are two very similar symbols there the the difference is if you look at this one um the line extends past the circle plus normally it's set on radius so you'll see it looks like that to start with and then you're going to select the diameter okay so now we have that shape it's fully constrained we're going to close that and voila we now have a loft that goes from a square to a circle and so that's simply that's how you do a loft and they're very useful and powerful when you're creating complex models if you want something to taper up from a square shape or a rectangular shape to a circle that's the way you would achieve it if you have any questions feel free to put comment below and i'll do my best to answer the questions now let's take a look at a sweep what i'm going to do is i'm going to rename this body i'm going to call it loft body so that'll be our loft and we can turn that body off go back in our pop create a new body we're gonna rename this one to sweep body so the difference between a loft and a sweep is the sweep is gonna run along a line so we can cause it not to go directly between one point and another but we can get it to go along a line so what i'm going to do is i'm going to create a sketch of my shape that i want to move along a line so i'm actually going to do it in this plane in there i'm sorry in this plane in the yz plane and for another reason then it just it looks cool that's all and i'm going to take a simple square again because the shapes i'm doing a simple they don't have to be simple but i'm doing that because i'm trying to show you how to do the sweep or the loft i'm not really worried about what the geometry is that i'm sweeping or lofting so you can make it whatever shape you want it to be so i'm going to do the same thing with this square i'm going to make those equal and i'm going to dimension one line now we'll tell you that i have increased the size of my icons up here and i did that because somebody asked me if i could do that or if that would be something that i would consider to make it easier to see for some people i'm interested in others input if let me know what you think if you like having the larger icons if you don't like having the larger icons also with the mouse i've made that larger so it's easier to see what i'm pointing at but if you don't like it let me know or if you really like it let me know that too okay so we've just done a fully constrained square and so again we have a square and now we want another sketch and i'm just going to rename this sketch first i'm going to call this profile sketch and then i am going to create a second sketch now this sketch is going to be of our path and so you can see where my my uh square is i want to make my path on the x y plane and my path is simply going to be a line i can make it a bezier curve which will give us a nice curved line so these these b splines you just it's just very similar to um using the polyline except for the bezier line will make a curve when i when i draw that type of shape so if i go here here here here and here for instance now you see it trying to smooth that line out and then once i've done that i can pull down the points move around the line to get different shapes pull down this point let's get it an interesting shame you can obviously you can dimension that as to how you want it to be so that is going to be my path and i'm going to close that so now you can see i have a in the middle of our screen you can see i have a square and i have a line and now i'm gonna do is i'm gonna rename this sketch to path sketch because that's our path and i'm going to select the profile sketch i'm going to hit sweep and it's going to say we have the profile which is the profile sketch is already selected and then the path to sweep along i'm going to select an object i'll select that guy and you can see already that it has created it so i'm gonna say okay and now exactly what it's done is it's taken that square from here and it's run it to here so when it when it takes that shape it will run that shape along the path and if i turn the path sketch on and you can see that the path is right in the middle there and right in the middle there so what it's done is it's walk that shape along that path but it's keeping the same profile the whole way along now we know with the loft that it's a taper but in this case it's just a straight path we can change that so so what we're going to do is we're going to add a second profile and to do that we're going to add a sketch and we're going to do the sketch in the yz plane that's the same plane that this square is in and we'll say okay and we'll zoom into the middle here we'll draw a reasonable size circle from that point there up to here say close and now what we want to do is to move this circle to somewhere near the end of our path now what we could do obviously is if we had our circle over here already we could then draw the path between those points but again i'm not going to go into all that detail i'm simply going to offset my sketch one more time maybe about 500 in the negative and because i want it to be roughly near the end of that path i'm gonna bring it up a little bit in the x direction just until it looks close enough so that we can demonstrate the effect and then what we do is we go into our additive pipe so where this is called a sweep a selected sketch along a path it actually creates what is called an additive pipe so don't get confused with that and we're just going to double click our additive pipe and then at the bottom of our additive pipe there's a a choice to go with multi-section so it's on it's typically on constant section you're going to select multi-section and then you're going to add a section i'm going to add that circle and now you can see if i close that you can see it's basically transitioning between our original square along our profile line and it transitions to a circle so again these this is a complex modeling technique because getting this absolutely right into what you want it to be can be a little difficult but i just wanted to show you how that sweep works probably when i use it the most i use it is just with a regular profile it goes all the way through i i don't usually transition because the transition is going to be fluid between those who's going to figure out how to go from a square to a circle over that length but not always uh something that you can you can easily calculate or predict so from your point of view i obviously know it's there it's a useful technique and it's something that you're able to use to create complex models again i would mostly use that just one profile come through but you can have multiple profiles through here so i could have a second square another circle and then another circle so eventually making all those parts in one sweep or one additive pipe it's really good if you're doing cables or pipe work stuff like that where you want to you want to model a cable you can just take that circle and run it along that path and then you have a a cable looking model so hopefully that's clear and easy to follow if you have any questions feel free to leave them in the comments below and i'll do my best to answer them so with that done i am going to hide the sweet body by pressing the space bar i'll go to my part just double click it to make sure that is the active part add a new body i'm gonna rename this body we're going to call this one spiral sweep and what we're going to do is this guy here we will be um creating a spiral sweep so the first thing we're going to do is we're going to create a drawing and we can do that on the x y plane say okay bring that draw into the middle and we're just going to do a circle and we're going to create a circle there and give that circle uh dimension oh again we're tiny here so i gotta make it bigger we're gonna make that three millimeters i keep zooming in by mistake so i'm gonna zoom back out and i wanna move my circle over here somewhere and there we go and then we're going to do a dimension from the origin to the center i'm not going to worry about what it is at the moment and we're going to do a dimension from the origin to the center in the vertical direction and now we can decide so if we're going to do a helix or a spiral this guy is going to go around this axis so if i have a three millimeter diameter and i want to have let's say a four millimeter hole in there i need the distance between here and here to be two millimeters because there's going to be another one of these on the other side so if this is one and a half then so one and a half is the radius from that center point to there and i want this to be two so i need this to be three and a half three point five and then i'm going to make this one millimeter above the center point so that is my sketch that simple i'm going to close that and now i'm going to zoom back into there and i'm going to hit the spiral so sweep a selected sketch along a helix so our sketch is selected and actually i'm going to rename my sketch i'm going to call that helix sketch and select that sketch hit that helix hit this button here so it fits in and now you can see it basically made a spring shape i have a four millimeter hole in the middle three millimeter diameter of my spring and then over here this tells me what mode i have in so i have a pitch of 4.6 and a height of only 14 so i'm going to create and make my height 40. so we got a bit more spring i hit enter there so it closed so i just double clicked it to reopen it now you can see a little clearer the pitch and you can see the effect if i lower that pitch i'm gonna have a tighter spun uh spring and it will give you this warning here if the helix might be intersecting or of course it's intersecting if my pitch is only 2.67 so my pitch has to be at least 3.01 to prevent that to prevent that from intersecting and so right now i have it in a pitch and a height mode so i can tell my pitch the pitch is the distance between each coil and the overall height is 40. so i can change that and i can have it pitch and turn sometimes with springs you'll have a pitch and a number of turns on that spring so you might want to have a round number let's go with 15 turns i keep pressing enter and closing that so 15 turns so now i know i have 15 turns with a pitch of 3.01 now i can also change it so i have height and turns so now i can say i want it to have 15 turns on my spring but i also want it to be 45 millimeters tall so those are your options you can increase the pitch by setting it pitch in height or pitching something if i increase the pitch it's going to open up a little bit if i decrease the pitch it's going to get tighter and then finally i can do this clap this cone angle so i can change the angle of it so that it now it's going up at an angle so it's wider at the top than it is at the bottom and i can change that angle and do all kinds of crazy stuff with this so it's that simple to create a helix and typically i'd use this for springs so that's why i showed you a spring but you could use it if you really wanted to [Music] if you really wanted to you could create um a thread with this but i prefer to use the fastener workbench and i'll show you that in a different video but for now that's this is basically the helical sweep if you have any questions on it feel free to leave a comment below and i'll do my best to answer your questions i hope you've enjoyed the video um there is a little bit of bonus at the end i am going to show you how to um constrain the the path that i drew for the other sweep i didn't want to do that in the middle of it all because i thought that might make it seem more complex than it really is but i will constrain that path to show you how to constrain a path and then hopefully you'll consider subscribing if you've enjoyed the video give us a thumbs up and if you're interested in supporting the channel please feel free to subscribe to our patreon uh the link is in the comments below thanks okay so as uh just a little bonus or just just a for completeness i'm going to show you how to constrain the additive pipe path or the sweep path if you remember we did a path sketch i'm just going to turn off that that spring first i'm going to turn back on my sweet body so let's just put that in the middle okay so what we're going to do is we are going to turn off the additive pipe turn on the path sketch remember we do that with the spacebar so it toggles it on and off that's easy to do if you look down here it shows you my space bar is like this little weird symbol so if i press space space you can see it's a weird symbol down the bottom there that that means space okay i want to edit the sketch i'm going to double click it and it's really quite simple to constrain the sketch i'll show you how so we're just going to take some dimensions from here everything's going to go off this origin point so i'm just going to accept whatever the dimensions are because i don't honestly don't care about them and these are all the vertical dimensions so that's it dimension that way then i'm going to switch to the horizontal dimension and we're going to dimension them that way so basically what we're doing is we're constraining these points and that will then stop that curve from being able to move so simply selecting those last one missed it hold on last one and now we have a fully constrained sketch and of course you can drag around your dimensions so you can see what they actually say me personally i when i use these curves like this i'm generally just trying to get a shape so i'm not really all that worried about the dimensions but it is good practice to constrain the sketch so it's constrained now so if i want to move these points i just change these dimensions and that will change that curve but that's how you would constrain the sketch hopefully that makes it clear and i just want to make sure you knew you can constrain the sketch i just didn't do it um actually one of the interesting things if i make that 500 millimeters and then i close that and i turn back on my additive pipe you'll see now that my part has actually changed because i moved the curve and in fact where this curve comes down the bottom here it's all going inside out so it's made a very interesting shape in doing that um so again you would just play with those those dimensions to get what you want to get the shape that you want uh the additive pipe is quite forgiving and he actually comes up with some pretty good shape so hopefully that clears things up makes it easy for you and if you have any questions again feel free to leave them in the comments below you

Channel: Adventures in creation

Views: 29,734

Keywords: FreeCAD, CNC, CAD, CAM, CNC routing, Design, DIY, woodworking, 3D printing, maker, creativity, art, crafts, Blender, Inkscape, Prusa Slicer, OBS

Id: Px1bkazmFH8

Length: 28min 48sec (1728 seconds)

Published: Sat Apr 17 2021