Progenitor of the Weird Knife Wednesday feature column. Is “column” the right word? Anyway, apparently I also coined the Very Specific Object nomenclature now sporadically used in the 3D printing community. Yeah, that was me. This must be how Cory Doctorow feels all the time these days.

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Cake day: July 20th, 2023

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  • I’ve just been using FreeCAD anyway, topo naming be damned. It hasn’t really screwed me on any of my projects once I figured it out, and I reckon that once they have that fixed it’ll just be a nice bonus. The only bugbear is that in its current state FreeCAD really wants you to design parts “its way,” whereupon if you don’t it’ll bite you in the ass later into your project. Some trial and error on my part was involved.

    The things that’ll get you are attaching sketches to faces or parts of your object, and if you reconfigure your object(s) to the point that new edges are created or removed it’ll break your fillets and chamfers. There may be other caveats for people using other workbenches or doing more advanced design than I’m doing, but I have no insight into that.

    For the former issue I just… don’t do that. I’ve never found a real compelling reason to attach a sketch to the geometry of another object versus just placing it separately, and for the latter you just have to do all your fillets and chamfers last, or not at all. Instead, I tend to work them into my sketches and the base geometries of my objects anyway, which is more flexible and in some cases easier (and in some cases not).

    I don’t think anything significant is going to change between the current release and the next one in that regard. All your old workflows will still work, it’s not like they’re going to take any capabilities away from you.


  • Every man has his price at which he’ll abandon any cause. Running a business is hard – It’s a big gamble and full of costs and expenses, you have to warranty the crap you make, source parts, fight with vendors, the whole lot. It’s a pain in the ass. But taking a big cash payout is easy.

    I’ll bet these guys had student loans. And I’ll bet you they don’t anymore.




  • If you want an identical texture from the plate on both sides, you could split your model in two laterally and print both finished faces downwards against the plate, and then glue/screw/pin/otherwise attach the two halves together afterwards.

    Doing this with an inlay for the two colors would be possible, i.e. with a filament change on the same layer. If your colored bit is a separate layer on top of the other stuff that plan won’t be possible.







  • No. It’s a Moto Z4, which is compatible with Motorola’s “Mods” ecosystem which are a variety of accessories you can stick to the back. For data transfer they connect to those pads via pogo pins.

    There are battery extender backs (which I have), a full-on gamepad case (which I also have) and also a 360 degree camera, a backplate that adds wireless charging, a mini projector, a beefed up speaker back, and an entire replacement Hasselblad camera you can stick on it as well. There was going to be a slide out physical keyboard module, too, which unfortunately turned out to be vaporware.




  • Was it actually him? I was under the impression that history did not relate what happened to him afterwards, nor who he was. That’s not to say the CCP did not murder a couple of thousand people during the crackdown regardless, because they did, but I have never seen a verifiable claim that a picture of any particular corpse actually was the Tank Man. There are numerous theories I’ve seen floated over the years alleging what may have happened to him afterwards ranging from him being caught and imprisoned, executed, living anonymously in China, or fleeing to Taiwan. All of them are unverified and, of course, mutually exclusive.

    The tank operators absolutely did attempt to (and succeeded at) avoid running him over. That much is plainly visible in the video. Whatever happened after the video ended is undocumented and pure conjecture. Plenty of well documented atrocities actually were committed that day, before and after that moment, so there’s not much sense in inventing new ones and bickering over details we haven’t actually got.




  • If you have that much warp you either have a temperature gradient problem, i.e. your enclosure is not enclosed, not retaining heat, or is too cold, or in extreme cases you have a part that’s just not going to work with FDM printing in ABS or ASA (or probably nylon or polycarb either, at that rate). I think you were on the right track with your initial assessment.

    Do you have a build chamber heater? My Qidi has one, and I feel like it’s basically cheating. Especially compared to my last printer. It allows me to Just Print with ABS without any of the prior nail-biting or headaches. It feels kind of weird.


  • I put the build plate in place as normal, but with a layer of kapton tape applied to it. (My printer won’t work without the steel build plate installed; my Z home sensor is magnetic.) In my case, I have a smooth backed one that doesn’t have the texture on it. You can apply it over the textured side of your build plate, too, but it gives you a resulting bottom surface that’s kind of weird and lumpy.

    Kapton tape will work in a pinch, but covering your entire build plate with it is a pain in the ass with all the seams between each strip. I get big sheets of the stuff like these ones, and do it all in one shot. You can pretty easily trim them to fit whatever size your printer’s built plate is.

    Remember to readjust your Z offset after you apply the tape because you’ll have to account for its thickness.



  • When I print ABS/ASA, I print it on a kapton sheet with hairspray as an adhesion aid. My printer (X-Max 3) does have an enclosed and heated chamber as well. I have not had an issue with getting parts off after the build plate has cooled. However, the addition of the kapton sheet means that the nuclear option is always available: Peel the sheet off along with the part, and put down a new one.

    They cost like 50 cents each in bulk. The skinflint in me prickles at this, but that’s a lot cheaper than having to replace a borked build plate. I have not had to do this with my current printer, but I did with my old one once.


  • I generally do them by locating the center point, constraining the radius, and then the angle. The angle tool is a little janky specifically on arcs, but it does work. Or if the ends of the arc are fixed to something also immovable, you can just do the radius and angle and use the coincident constraint to stick its endpoints to the ends of other lines and leave the center point alone.

    Yours was an interesting approach. I probably would have used a bezier for the pointy end of the heart.


  • Honestly even at this price point I don’t see much use for a machine like this for hobbyists. Plastic SLS printing only has a few advantages over the significantly cheaper and widely supported FDM machines most of us use. SLS printers can create overhangs and do “print in midair” tricks that FDM can’t because the partially completed part is supported by the unfused powder, and they theoretically produce parts that are isotropic, i.e. there is no difference in layer vs. planar adhesion and they are as strong in the Z axis as they are in the X and Y. This might matter for mechanical parts, but it’s not terribly important for the vast majority of people who are just cranking out low-poly Pikachus and Deadpool busts or whatever.

    Yes, I can definitely foresee this being a mess. You know how people clutch their pearls over microplastics? SLS powder is microplastic, factory made, in a bucket.

    It would be a different story if we could get a metal-sintering SLS machine at this price point. Even if it could only do aluminum, that would change everything.