• 3 Posts
  • 37 Comments
Joined 10 months ago
cake
Cake day: February 15th, 2024

help-circle
  • You could also probably use Inkscape to get DXF files for both sides of the coin, making sure the size is right and that the path accommodates the width of your letters/strokes. Then, hypothetically, you should be able to import the files as drafts and then convert them to sketches with the press of a button (in reality, this crashes FreeCAD for me lately, but it could be a quirk of my setup). If you’ve already modeled the coin itself and use the new sketches to pocket into the existing solid, IIRC it should work okay. FreeCAD would not extrude a non-contiguous sketch into multiple solids, but I think it’s fine as long as the end result is still a single body.





  • First, a little plug for !cad@lemmy.world because more traffic is welcome. The pinned post there is a fairly comprehensive list of viable 3D mechanical CAD suites. I’m a rank amateur with actual designing, but if you want someone to drone on at length about their business models and licensing terms, I’m your guy. (short version: “Fuck you, fuck you, fuck you, you’re cool, and fuck you.”)

    Now then… I also came from TinkerCAD, and I actually think the grouping and alignment tools lifted from vector art programs are super intuitive, and they almost provide a sort of design history if you use them right, but there are so many things that can’t be done quickly in TinkerCAD, and Autodesk also nerfs it for reasons that are commercially sensible but not technically necessary.

    Almost all parametric tools , and also most “grown up” (for lack of a better term) direct modeling tools can do the Boolean addition and subtraction that is at the heart of TinkerCAD’s “solids’n’holes” paradigm, often in a couple of different ways. For instance, to make your orange part there, I’d draw a 2D silhouette of the vertical view, then extrude (or “pad” or “pull”) to the height. Then I’d draw on that top surface, possibly with a reference plane set up first to avoid having the model too far up its own ass (i.e. the toponaming issue), making the shape that needs to be extracted. Then you can cut or extrude down into your solid. Most tools will know what you mean, but some might make you do use a distionct tool or manually do the boolean “difference”. You can then do the same with your hex grid, setting up a new sketch for that. Later, if (for instance) you wanted to have 12 holes or bigger holes, you’d just edit the one sketch. Your red part would be similar, but doing the back of it would involve extruding out from the new sketch. The power of sketch and extrude is, apart from the ease of implementing a parametric history, doing several things at one that would each have to be a manual hole in TinkerCAD.

    Finally, there’s the simple matter of fillets and chamfers, which TinkerCAD doesn’t support as an independent function. Manually adding them gets tiresome real quick and is the “killer feature” that made me realize I needed to move on. Other tools like loft sealed the deal. TinkerCAD is capable of some really interesting parts, but not efficiently.






  • Per the edit to the main post and in the interest of full disclosure, I had a filament break about 1/3 through, but that’s okay because the partial PLA print was nowhere near strong enough along the layer lines. There are plenty of decent 3D printed keyboards out there that just need some assembly and post-processing, so if this one doesn’t work within the constraints I’ve set, there’s not much point to it.

    Learned some stuff for future designs, though, so we’re all good. 😊


  • Most of my projects lately have been hand-wired keyboards. I like messing around with completely custom layouts and seeing what my home shop can handle. They almost all use the 3D printer somehow, but this is only the second one with a case that’s completely 3D printed. I’ve done one that was just rewiring a board with a broken PCB, three on laser cut aluminum I sent out to have made, then a few more with 3D printed plates or Masonite that my 5W diode could cut without too much trouble. There are plenty of 3D printed orthos and splits out there, as well as several nice 60% and 65% board that you print in multiple pieces, but my (admittedly somewhat arbitrary) goal for this project is to see how close to a “traditional” board you can manage as print-in-place on a garden variety Ender 3 bed.









  • I’m no professional, but it does seem that many of the ways to design around TNI, e.g. defining reference planes for sketches that are associated with geometry via shared variables rather than a face earlier in the tree, are ripe for automation and/or are very sensible to obfuscate under a layer of abstraction. TNI doesn’t strike me as inherent to the way designing a solid object needs to be, but rather that it’s difficult or impossible to avoid based on the code that actually makes a 3D solids kernel work. To my mind, it seems like awareness of its persistence is sufficient if you have a mature set of workarounds and heuristics that make the software act predictably. I suppose it does promote lock-in and precludes a truly complete and portable file format though; the solution is clearly for one of the big 3-4 industrial suites to open-source itself!

    As for that github table, I’m all ears about expanding it or correcting anything that might be wrong with it. The “real” one on wikipedia is rather daunting and necessarily for a broader audience.