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Show HN: 3D printing giant things with a Python jigsaw generator

by naggie on 1/23/25, 1:35 PM with 47 comments

  • by lucasoshiro on 1/27/25, 4:02 AM

    I'm really happy to see OpenSCAD stuff here in HN. Of course it has some downsides (not being able to measure an object is the main one...), but it is an underrated tool.

    I'm using it as my main 3D modeling tool for three years, and I even gave I course about it last year. No regrets, and I never felt that I needed to learn Fusion or similar

  • by jgoewert on 1/27/25, 2:29 PM

    This came up at pretty much the perfect time for me to try out.

    I started learning OpenSCAD over the weekend to try out an idea to 3d print a 70" dome to make my own Star Wars Battlepod after seeing that video on making the replica Space War cabinet.

    One guy got an acrylic forming shop to make him one about 10 years ago for $700, but I was calculating in how much it would cost to 3d print and stich a dome screen together. My test sample that I started used a sort of ribbed dome that I was trying to figure out how to split the file and bolt it together - https://www.reddit.com/r/openscad/comments/1i922ed/trying_to...

    I started playing around with thickness because at 1/2 inch, it was looking like about $200 in filament. But if I can reduce the thickness because of having the jigsaw edging to make it easier to align, it might get cheaper.

    Currently tried running this in Windows and it isn't happy. I'll make a Linux VM and give it a go again.

    >>WARNING: Too many unnamed arguments supplied in file in.scad, line 6 Geometries in cache: 20 Geometry cache size in bytes: 3802608 CGAL Polyhedrons in cache: 182 CGAL cache size in bytes: 0 Total rendering time: 0:00:01.063 Top level object is a 3D object (manifold): Status: NoError Genus: 1 Vertices: 39078 Facets: 78156 Num. beds: 0

  • by almog on 1/27/25, 12:30 AM

    > "The strength comes from the tightening/wedging effect when pulling the join apart. If the dovetail is tapered, the join can also tighten when it aligns too – this is highly desirable for gluing, as it means the glue will not be scraped away."

    While true, dovetail and other traditional woodworking joints borrow their strength from using the wood grain to support the joint.

    I don't know a lot about 3D printing but I'm guessing a lot of the assumptions about woodworking joints strength aren't applicable.

  • by nejsjsjsbsb on 1/27/25, 12:58 AM

    I been thinking an openscad->cura pipeline would be cool. This post is very similar and inspiring.

    Imagine running a custom action or pipeline and getting a physical object pop out in the shed. Pretty awesome.

    I also like the idea as git as the way to share and remix 3d printing instead of (as well as) the various STL sites.

  • by ramboldio on 1/26/25, 11:15 PM

    A big advantage of this technique is that the assembled model is 'isotropic'. If it was printed in one piece, it would be easy to split along the layer lines.

    But when printing the plates separately, every face is equally strong.

    Great project!

  • by nine_k on 1/27/25, 12:30 AM

    This is cool. This is also massive. I wonder how much e.g. the arcade machine housing costs just in the filament used, and how many hours did it take to print.

  • by CharlesW on 1/27/25, 1:20 AM

    A linked-to inspiration for this — printing an arcade cabinet for Atari's Space Race (1973) — is a great watch too: https://www.youtube.com/watch?v=SONO6LTHuR8

  • by tda on 1/27/25, 6:17 AM

    In similar vain, but the with cadquery and Jupyter notebook is the screwdriver stand I once made:

    https://github.com/tdamsma/Screwdriver-rack

  • by camel_gopher on 1/27/25, 4:15 AM

    I 3d printed puzzle pieces using Go to generate the join sections. Figuring out the right tolerance takes some trial and error.

  • by batch12 on 1/27/25, 12:55 PM

    I wonder if leaving some of the base intact would help with the artifact issue. Instead of cutting the teeth all the way through the whole section, leave a few mm solid on each side and reduce the height of the teeth to compensate the opposing base layer. It might add a bonus of hiding the teeth, too.

  • by MisterTea on 1/27/25, 4:28 PM

    While this is nice for things like the speaker enclosure I cant help but recoil in horror from the 3d printed arcade cabinet - so much plastic. I get how this enables shapes and other niceties but between aesthetic and the environment I'll take boring and recyclable any day.

  • by ashoeafoot on 1/27/25, 6:35 AM

    Skipping teeth? Why not scale the whole series of dove tails for detected cases?

  • by SSilver2k2 on 1/27/25, 9:31 PM

    Take a look at Luban3D. It does a lot of the automated mesh cutting.

    https://www.luban3d.com/

  • by ajolly on 1/27/25, 4:14 PM

    This is great I'm going to have to try this out. I've got my own openscad dovetail joint scripts, but this seems more refined.

  • by DonHopkins on 1/27/25, 1:46 AM

    Oh man, now I totally want to 3d print a full sized interlocking Han Solo in Carbonite with embedded magnets to stick on the front of my refrigerator!

    Maybe I'll have to get huge commercial refrigerator for the proper effect, but it will be worth it.

    3d printed life size Han Solo in Carbonite replica Part 1:

    https://www.youtube.com/watch?v=lOj3yZ-iMjM