 So for those of you who've been sort of in a maker space and kind of eyeing the 3d printer, but don't really know what to do with it and would kind of like to try to figure out but have no idea where to start, this is the kind of talk for you. Nils Pickert is a model railway enthusiast but he also plays with the big heritage trains and he's a physicist and he described himself as a standard nerd. So I guess that's something we can all agree on that we all are. He spent some time getting to know FreeCAD and will let us know about the ins and outs and what to do and what not to do. Nils, please go ahead. Thank you. So thank you for the nice introduction. I would like to share you just my, the summary of my first few months with FreeCAD and I'm by no way an expert. So please be patient when I'm telling stuff which you think is completely wrong. It might be completely wrong. What's FreeCAD? So FreeCAD is open source. It's a CAD program. It can do parametric modeling. It can do basically everything. There are finite element simulations and ship building modules and everything. So this is a very, very powerful program of which I just touched very, very little of the surface. But this very little of the surface is sufficient to do what I need to do for model railway stuff. So we'll do a workshop after this talk. So I answer questions and of course we can do construction in FreeCAD together. And so just let's dive in the talk. So what do I do with the FreeCAD software? I'm basically constructing stuff for my model railway. There's some larger structures. So there's the module basework, which is wood or something, what's medium dense fiberboard to hold the tracks. And I'm also doing some stuff for 3D printing to print these little locomotives, for example. They are modeled after, this one is modeled after a Portuguese prototype, but I also do some German prototype modeling. And the manufacturing is laser cutting for the baseboards and 3D printing for the modeled stuff. My cut experience is very little. So in 1992 I did a school internship for two weeks and I had some contact with AutoCut. Back in the good old days with floppy disks and it already had a graphic tablet and a big monitor, but I think it was everything black and white as it was in the 90s. Then in the also early 90s we had this autosketch, which was a very rudimentary cut thingy which ran on the PC. And then later on I did some stuff in Inkscape and Tinkercut and as I ran into limits with what Inkscape and Tinkercut can do, I started using FreeCut a couple of months ago. So two caveats. So first I'm not a really expert in CAD and second I'm very old and might not be up to date on how to use modern software. So why did I choose FreeCut? Basically all this Tinkercut Fusion 360 and everything cloud-based, web-based is quite nice, but you don't have full access to your data. So if you save something, it's in the cloud and if Fusion decides you don't have any access to it anymore, then it's gone. So I don't have any control about my data. Second point is Fusion 360 used to have a free model and then it was a free model if you register every year and then it turned into a subscription-based model. And now I think you have to pay something like 200 something euros per year to use Fusion 360. And if I have to pay 200, 300 euros for just printing one model engine per year, I can also buy a model engine per year or something like that. So this is also kind of no-go. There are two open-source cut systems which are very easy to find. So one is OpenSCut, which is more programming-like. This looked a bit scary and even for somebody who's doing his slides with Tec, I think I really like to do clicky stuff. So I choose to use FreeCut. FreeCut is also free open-source everything and you can do programming somehow, but most of your user interaction is by mouse. Okay, to get FreeCut, FreeCut.org has the latest builds as binaries. You can also get the source code there and just install it for all major operating systems. We can run it on Linux, Mac and Windows and probably something else as well. I've been running it on Mac and Windows and so far no difference is in stability and everything. So it's really working well. There's one thing you need to take care of. So I first installed FreeCut 0.18, which was half a year ago or so. And then immediately after I installed it, 0.19 appeared and I installed 0.19 as well. And at least on Windows I had two versions in parallel. So it didn't remove the old version, you had two versions in parallel. I ended up in sometimes using 0.18, sometimes using 0.19 and then sometimes my files didn't work in one version without any apparent reason until I figured out this 0.18 is still on the PC and I still had a problem with this old version. So when you install the new version and you don't need the old version for anything, just make sure that you clean it up. Okay, where to learn FreeCut? So FreeCut when you first look at it, it's complicated and huge and it's very overwhelming. And it also is not the most intuitive software, which is because it's a CAD program. CAD programs are not really intuitive. So there's the FreeCut documentation and also a spelling error, which I haven't seen. Even I looked at it five times. So the FreeCut documentation, Wiki, FreeCut, or getting started, it's pretty good. It's huge and you mostly have the problem, you don't know where to start. What I really liked was Flowey's Corner. It's a guy called Florian on YouTube. He's doing really good tutorials in German for version 18, version 19 and also some other CAD programs. He's a professional CAD instructor and basically everything I learned, I started learning on this channel and then worked from that on. If you prefer English, there's the FreeCut Academy on YouTube, where some of these tutorials from Flowey and a lot of other tutorials are on it. Easy to remember all, but the slides are in the talk description, so you can click on that link in the PDF. And of course your friendly Volkshochschule might have a training on FreeCut. So for example, this guy here, Martin Hasner, is a colleague of mine. He's doing FreeCut trainings at the Volkshochschule 4th in January and February. And you might have in your local Volkshochschule, at least in Germany, some of these trainings available as well. Okay, so let's have a look at the cut itself. So this is what it looks like when you started the first time trying to move there. So you start up with this screen. I already loaded a couple of files and you have tons of buttons and you don't know what to do with it. So the first thing you notice is you usually start in this start workbench, where you can't really do a lot of stuff. Workbenches are one of the basic concepts for FreeCut. So workbenches are basically like a real workbench, it's sorting of tools. So you have a specific task to do and you do that in your workbench. For my stuff, I use the part design workbench, the part workbench, the mesh design workbench and the tech draw workbench. You see there are a lot of others. There's finite elements, there's image, there's points and ray tracing and so on. I have no idea what they're doing. So far I haven't used them. The first thing you will do with any part you design is you start with a sketch. Sketches are the basic building blocks. They are 2D sketch and from these 2D sketch you can pet this 2D sketch up. The sketching up means you just add depth to the sketch and then you can create Boolean operations and modifications of that basic shape. So first you do a 2D shape, then you turn it 3D and then you have something like a sheet metal part or a sheet of wood part and then you can drill holes and chamfer edges and do stuff like that. Sketching is done in a specific coordinate plane. So when you start from scratch, you have the basic coordinate planes in the XY plane, the XZ and YZ plane like your normal coordinate system. And as soon as you have something in your sketch, you can also choose a face of that part or something relative to that part as a base plane for your sketch. But normally you can go with the coordinate planes and then translate the part later as well. There are some problems with sketches or problems with some things to take care of. So you can only create a continuous body from your sketch. So you cannot create two cubes from one sketch. You can only create something which has a continuous surface. It can have holes but you cannot create something which is two bodies in one sketch. So as an example, I just go here to the start new file, then go to the party sign workbench. This is what I need to do to start any new part. Create a body, create a sketch and then select one of the planes where I want to have my basic, my base set. For example, I create a circle and this I cannot pad because for some reason the circle wasn't drawn. Okay, now it's drawn and I can pad it up. I don't know why it's tortued but you get the idea basically. So you draw something and then you extend it to the third dimension. If I change that sketch now to have two circles, so another one here for example, the padding doesn't work anymore. So it's still showing the first one but not the second one. And this might create all kind of funny effects. So if you have holes, holes are fine but if you have something which is overlapping, you have one circle which is extending over the border of another circle for example, then you get really funky effects. Okay, sketches. Sketches need to be constrained. Constraint means everything needs to have a measurement to it. So if I go back here, create a new body, create a new sketch and then choose this plane. And I draw, for example, again a circle. The problem right now is you know it's a circle but you don't know anything about that circle. So to define that circle you need to put measurements on it. And measurements are these red things here. First we can put it, give it a radius, so let's give it 20 millimeter radius. I need to turn off caps lock. And then I need to define where it is relative to the origin. And I can do that by putting horizontal measurement to that. If I manage to click on the points, so I have now 30 millimeters from vertical and measurement and then I do another horizontal measurement. So one part you see already it's hitting the points is sometimes a bit hard because I was this point and this point. Here we go, 30. And now the circle turns green, which means all the measurements are done and it's well defined and FreeCAD knows where it is on the drawing. So it's also completely constrained sketch here. And then I can do new sketches or I can also pad it up. I extend it for 10 millimeters and now I have a disk. With this constraining, if you get complicated shapes then you might run into trouble sometimes that either for one measurement there are two solutions. So something if you just give, for example, a distance this line is 5 millimeters to this line it can be on both sides of the original line. And sometimes FreeCAD gets a bit confused and sometimes your line jumps over to the other side of the line you measured it to and you cannot really get it back with moving it or by adding other constraints so then safest part is delete the constraints again and start from scratch and measure again. Okay, this is constraint. So constraints sometimes gives you two solutions. Sometimes I also had some parts where it went completely bonkers. I have no idea why or what. So the easiest, the only thing I could do was delete the sketch and start again. So be prepared if you do something complicated. If it gets too complicated a mathematics might go into your way and FreeCAD sometimes goes strange. It didn't happen with 0.19 that often but with 0.18 it was quite often. The next important concept is this model tree. So when you create parts you have on the left and a model tree. So you have bodies, you have pads and pockets and stuff like that and below that you have sketches. This tree is kind of your history. So you create a body. A body is something, it's a grouping of 3D objects. I think it doesn't need to be continuous but you can also have multiple stuff sitting next to each other but it's basically something which has one coordinate system and is grouped together. Under this body you start with a sketch, you pad it up and then you do whatever you do to your padded up thing so you can create pockets which are creating holes into this object or you can chamfer it which means instead of a sharp edge you round it off and this is kind of your history. So this chamfer here for example is the latest action I did to this body here and if I need to change something before if I say this needs now to be 5mm longer I can go to that sketch, change that sketch and then it transmits the changes through the whole chain and also the chamfer is then moved to the place where I want to have it. So this is kind of a history thing of your model but also kind of a hierarchy of the model where you can have multiple bodies which are independent of each other so then you can create separate parts of your model which you model independently. So just let me do an example so I have now this pad here and I create a new sketch so for example I can create that sketch now on this surface to make my life easier I create this sketch so I select the surface, I select new sketch and now I put another circle in here measure it so it gets a radius of 5mm and it's measured to the horizontal and also to the vertical also 35 for example done and now I want to not to add some volume to it but to use that to create a hole so I say okay now punch a hole through it and this hole should be 5mm deep and now you see we have a 5mm cutout and you have here in the history of the original pad which I now decide I want not 20mm but 25mm and it turns bigger but the hole stayed where it was now I can do all kind of fancy stuff so I can select this edge here and I say okay now this edge should be chamfered by 2mm and so on and you see this operation adds to that history so if I chamfer the outside now or make it round it's added here and if I want to change the chamfer from 2mm to 1mm I can go back and just do it now I see the fillet here is gone because the chamfer is now the active state and to get the fillet back I need to activate the fillet again which is just by double clicking and then we're done okay this tree is quite helpful but there's also problems the internal data structure of freecut everything is relational or relative to something else so for example this fillet is saying okay this fillet is added to the edge I don't know which number it has edge 25 and then this action applies to edge 25 if I now do something weird and delete an edge or create new edges inside the earlier stages freecut is doing quite a good job to keep up to date but sometimes might not and this is really funky so when you have multiple things in your history here and then you go to the first sketch and add a line to that sketch or cut out something sometimes things go horribly wrong so my suggestion here is don't try to go back too often so if you do something complicated try to do it right from the beginning it's I know it's hard but it helps if you start here already with your final result in mind also helpful save intermediate steps as separate files so if you mess something up you still have your backup from sometime earlier basically the further you go back in the model history the higher the probability that you mess up something there's also something some operations are more robust than others so sketching and padding is quite okay holds like I did this one here for example this subtraction and addition is also okay but fillets and chamfers for example they can go easily wrong so if I would have created a more complicated part which has more pockets and more additions create this chamfers and fillets only at the very last step so I noticed if you do them too early then you'll run into these problems that it doesn't really know which edge you meant and stuff goes crazy when you have designed your part and want to use it more times you can clone it or you can copy it copying is just like you would copy with ctrl c, ctrl v or ctrl c, ctrl v on the Mac this copies everything including the dependencies and coordinate systems and everything so I've now copied it, added it and I now have something called body 001 which is the same body so let's just move it move it is done by placement, position and then you can move it along the different axis move it 5 now I have two disks and this is just a copy so if I change this part for example if I add another chamfer to this edge it doesn't show up on the other I need to make that body active to work on it double click on it select the edge chamfer it doesn't show on this one if I take this body and create a clone that's this one looks the same it says body 02 so let's just move that in the other direction minus 15 but this one is an exact copy so if I add an end for example 5mm for this chamfer it also applies to this body and you only see that when you go one level deeper in the tree so this is a clone this is a copy of everything to do this you can do that in the part design bench you can also do it in the part work bench which has a bit more options to copy and clone and boolean operations and so on so play around with this part work bench as well okay there is also a translating and mirror ring so if I want to create a mirror object of that for example I can mirror this one I cannot mirror this one because only additive and subjective feature not clones can be mirrored so I need to go to this one I did the clone go I only mirrored the chamfer I need to mirror the body okay so I cannot add a mirror complete body I can mirror some features of that body and you don't see it because it's already symmetrical so you see there's all kind of weird stuff which I haven't really used so I go with copy and clone and rotate and most of the stuff I can do with that also this is something which you should do at the very last step because due to this relational data you can mess up stuff very easy if you have multiple copies and then change something in the original one and then something in the relations goes missing on the way copy clone moving as a last step when you design some stuff this is also something which I learned through pain think about the symmetry and where you need the final part in your model so for example for this locomotive I designed it's choosing if you pad up in this axis or in this axis is sometimes interesting or for the engine hood here it's probably easy because you always want to pad it up along the axis of the locomotive because that's where the symmetry is but for example here for this for the house here for the cabin, the engineers cabin you can do it this way or this way and depending on which way you do it you should do where subtraction where shapes or easy shapes also here for this for these ventilator thingies here it was very helpful to place the engine that the central symmetry axis is on one of the coordinate system axis so the basic which Y plane I think it is is going through this mirror symmetry axis of the engine so I could just mirror these parts and need to move it quite a lot of times also try to model that you don't have too many dependencies so it's easier to have lots of little parts than adding everything to a big part the bigger the part the more dependencies you have and the more chances you have to mess up so each of these ventilator thingies is a separate part this is a part, this is a part, this is a part so you end up with a lot of parts and a lot of copies of these parts so if you look at these for example these are all the individual parts for 3D printing it's not so critical because I merged the mesh afterwards but for the construction it's really nice to have simple parts which don't have too many dependencies now you have your construction you want to get it into your laser cutter or into your 3D printer and there's a workbench for it for laser cutting it's relatively easy you just do a technical drawing where you need so you have your 3D model you need to choose the projection you want like this you select the part and then you add it to the drawing workbench which looks like this and then you add this part in your viewing in a one-to-one scale and you're done I don't show that yet because we're getting short on time I think we have some time for questions and then I can show that in the Q&A afterwards then you can export it as DXF or SVG file laser cutter and it should work if you go for 3D print there is the mesh workbench and this is also not really complicated so you select your mesh workbench where is it mesh design select the parts you want so for example I select everything I go to meshes and say create meshes from shape and then it creates for each of these parts a mesh so if I turn this on for example then you see this is one of these ventilator thingies as a mesh let's turn this all off so these are all individual meshes the main one was just select them all and merge them into a big mesh which you can do just select all these meshes and where is it somewhere there was a mesh yet merged the complete mesh and then when you have that mesh export as STL and you are done let's export here we go you can mesh it as an STL file you can go in mesh lab and clean it up a bit but so far it worked directly from FreeCAD couple of things FreeCAD is not a perfect photorealistic modeling thingy so if you need something like a thread like helix FreeCAD is doing this as a normal cut drawing so it's basically a hole which has a note on it and saying this is an M5 thread or something like that so you don't have the actual helix in that thread if you need to model that helix there's a helix tool to do it but this also has some limitations and you can also only do full turns of the helix and you might create a lot more problems with that so if you need to print that thread or the helix for the thread or screw this might get complicated so I haven't tried it, so anything I needed only had through holes so no threaded holes but there's a problem that you cannot create every detail as you would like it Summary, extremely powerful can do a lot of stuff, has a learning curve but the good thing is it's actively developed it's free, so there's lots of stuff coming on so if you follow FreeCAD news on Twitter so every day or two there's a post on a new module on some new functionality they're heavily working on the UI to make it more user friendly so there's a lot of stuff ongoing so it reaches 1.0, it will be really awesome so far I've only touched the very very surface of it and I still run into all kind of trouble so it has a learning curve the only negative thing is this relational data model which I mentioned that sometimes stuff goes weird when you delete an edge this definitely needs some work before 1.0 but this is also something where big commercial CAD systems have problems so there are if you go to NXCAD or something they also had these problems in the beginning and this is nothing bad against the FreeCAD community or the FreeCAD programmers, it's just that this is the really really super hard part and it's quite amazing already how stable FreeCAD is, to be honest okay then I would be done with my talk I hope you're still awake and would be open for questions Perfect, thank you so much, thank you also for the very technical presentation I think that's always fantastic when we actually get to see what's going on we do have some questions from the SignalAnal the first question we actually had is whether you've had any experience of 3D scanning with a cheap stereo camera in connection with FreeCAD stereo camera not, I tried some photogrammetry I measurably failed the problem with this stuff is you create meshes you can edit meshes in FreeCAD but I think there are better tools for it so if you look at this for example these are, I don't know how many vertices so I have no idea how to edit these actually I think you can edit them but I'm not sure if you want to edit them I would try Blender or something which is more mesh oriented understood, I think that hopefully answers the question the second question we had was can FreeCAD import step files and save models as step files import, yes export, good question I need to choose something before export never tried it step with colors so yes, it's possible I don't know if it's working well or not there are a couple of formats for different CAD formats so I should try that I don't have it on my laptop here but on my work laptop I have an XCAD and could try to import the step there but there is interface in both directions to various CAD formats okay, perfect, I mean I guess that answers the question anyone who wants to try it, feel free what's your best non-technical tip for someone who is just starting out with 3D printing and CAD design non-technical tip for patients so this is this is something I think construction is painful and there's a reason why engineers have to study so long for it I'm a physicist so I'm also just an amateur on that there are a couple of things where you need to take care with 3D printing thinking that you're always adding some stuff to layers and layers and layers so if you have something which would float in air when you create these layers then this is something you need to take care of but I think the best thing is just try it be patient and try it so you will mess up, you will create horrible spaghetti stuff out of your 3D printer or horrible mess of what you call this liquid stuff of acrylic but you can clean it up and start again that's part of the fun don't let it run unattended overnight if you do it the first time sit next to it we have a question about 2D architectural plans can I do something like DWG files, DXF files DXF yes DWG as well DXF I already tried there is also architecture model workbench there is a special this ARC workbench which has special building and drawing features but I also haven't tried it so there is create a building, create a layer of that building this is very powerful I haven't tried it but when you follow FreeCAD news on twitter they post a lot of building projects done with FreeCAD very definitely possible thank you so much for your time thank you for the presentation here for the actual doing it see you there in a minute