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Joined 1 year ago
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Cake day: June 22nd, 2023

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  • It’s all with respect to humans. Humans aren’t making the bird nests, so they’re natural, not man-made. Our houses don’t over naturally, we build them.

    From the bird’s perspective, sure, nests might be bird-made and humans are part of nature. But at humans, we’ve also done a ton to shape the world and separate ourselves from nature. If your house were a fire-heated lean-to in the woods, there might be less a distinction between it and “out in nature,” but if you’re living in a city or town, your immediate surroundings probably have been heavily constructed and modified by humans.










  • Oh boy, I keep a page just for this!.

    I need to update it (for example, Arachne perimeters in PrusaSlicer now let you print extra thin perimeters), but it’s useful to have a reference for common tolerances/dimensions like screw holes.

    But a couple of my little additional pet peeves:

    • Don’t put fillets on the underside of prints (against the bed). The nearly-flat angle always droops and looks bad. Use a chamfer instead, or make a fillet that actually starts at 30° from horizontal.
    • The weakest direction is between layers. Design your part such that you can print it in an orientation where the thin/weak parts aren’t printed where the layer lines can snap (eg, print it flat vs vertical)
    • Just like the straight lines inside screw head holes, thinking ahead in your design can prevent/minimize the need for support material. The earlier you start thinking about this in you design, the easier it will be. For example, can a part be designed with a 30° slope on an underside instead of being flat? Can you think about your print orientation early in the design process to avoid overhangs?
    • Chamfer of fillet inside corners, if it’s a structural part. This will greatly reduce stress concentrations.

    Personally, I don’t use 3 perimeters on most of my prints. On my prusa, they look totally fine with 2 perimeters. I only switch to 3 if I need the strength (which also almost always means I’m printing in PETG, rather than PLA, FWIW).





  • I’m also team onshape. I have a powerful desktop, but I still end up doing CAD from the couch on my 6-year-old Chromebook, so onshape is a champ for that. It’s also nice for collaborating, which I do when working on bigger projects with my fiancee.

    I got started with it entirely from the tutorials provided by Onshape itself. The learning curve was a lot less steep than I expected.




  • What kind of curling issue, and did the Hilbert curve help with that?

    I’ve found that I’m rarely doing something where my top layer lines matter. Usually, I get my finished surface by printing things face down on a textured sheet. This works for probably 95% of the things I print whereki care about finish. The others I’ll turn on ironing, but that’s probably way slower than the Hilbert curve.