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Comment by Brian_K_White | Hacker News Reader

It's a lot of work to make models that are useful in real life, but for some things it's worth it because it's sooo nice having 2k of plain text that describes an entire object, and it's even fully parametric, and it even comes with a customizer panel for the parameters, so every model isn't just a model, it's a model generator app, and even has meaningful diffs in git.

The same model in freecad is like 6 megs of zipped xml and realistically not nearly as usefully parametric.

That couple-k of plain text is such a huge deal that it makes all the other difficulty worth it for mechanical/functional stuff.

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OpenSCAD is the only CAD tool I use. I can'd figure out how to operate a graphical 3D software with a 2D GUI so it's just easier to describe things mathematically.

I just wish it had operations for subtractively chamfering, rounding, etc. as doing minkowski() with cones and spheres to achieve that result can be unwieldy.

Do you know about BOSL2? It can do rounding or chamfering very easily.

cuboid([20, 20, 30], chamfer=5);

A few years ago I made a little module rounded_cube that generates a cube by drawing 1/8 spheres wrapped in hull, andnsince then I've been using that for everything, making inside fillets by using a rounded cube as a cut shape. Since it can generate a hollow box with a desired wall thickness, you have the shell of an enclosure box in a single call.

Over time I added other things like a single linear fillet, a single radial fillet, both interior and exterior, convenience things built out of those like a screw post with a fillet base etc. But really I always end up just using mirror_copy and rounded_cube a lot.

There is a scifi book series aboit a programmer who gets zapped into a fantasy world that has magic, and he becomes the most powerful wizard in the world because he applies the coding concept of reusable components and building big things out of smaller things and automation, which none of the other wizards ever thought of.

openscad is like that. To get anywhere you first have to build a library of useful higher level things out of the low level things. Like forth or assembly, or really all programming I guess.

I find that I'm often making one-offs. I take a part I designed and I need a slight modification for it for some reason.

Fusion is great for that as long as there's not too many parts. But sometimes I'll want a new variant or a series of new variants.

And reaching for python makes that easy.

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