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Has anyone have good success using AI generated CAD parts? I’ve been trying but it’s always 95% there, but with all hardware, you need 100% right. It’s often quicker and cheaper for me to do it by hand (but I was a mechanical design engineer for about a decade prior)

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Just this morning I used OpenSCAD for the first time. I got Gemini (just the chatbot, no harness or MCP) to help me design a water-bowl holder for our senior dog (she kept knocking it over).

It was probably an easy model to get right, since the only "critical" dimension was the radius of the interior. But I was able to tweak the numbers on the support length & some other details relatively easily, and I had a working solution 2 hours of print time later.

(I had a CAD class in highschool, but haven't used it since).

I suspect this may be another case of "LLMs are mainly good at things you're bad at."

assemblies and tolerances are where AI generation quickly gets hard. but, for simpler things, it can be surprisingly good, especially for people who has no CAD knowledge. it certainly might feel a bit like brute-forcing through the LLM - but this also applies to vibe-coding..

A screw can't be 99.9 percent correct—it has to be 100 percent correct. Microns matter.

Claude Code: Oops, I am sorry but I was wrong.

As you say it is quicker to do it by hand. Now.

I certainly wouldn’t entrust this job to a general-purpose (universal) tool that gets it 99.9 percent right.

But a domain-specific harness? Maybe it could work.

Hardware and engineering dont tolerate hallucinations, trust-me-bro numbers, deviations.

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