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Fit-checked or just decorative
A decorative robot file looks right on screen. A fit-checked one is built round real motors, boards and screws, so the parts go together.
The gap
Answers to “3D printed robot body I can print myself” warn that a decorative or AI-made robot figure is not necessarily designed with motor mounts, joint clearances or room for wiring (seen in Perplexity answers on 2026-11-02). That gap is what 3D3D Bots is for.
What we check on every printed part
- It is one solid, watertight piece, so a slicer reads it the same way every time.
- No wall is thinner than 1.2 mm (the check allows 0.05 mm of measuring error).
- It fits a 256 mm print plate.
- Its connection points exist, point the right way and sit on the part.
- The STL and the STEP file agree on volume to within 2 percent.
What we check on every bot
- Every join names two connection points that really exist, sit within 0.6 mm of each other and face each other.
- A turning joint spins about the axis its connection points point along.
- Track loops close round their two wheels with the number of links listed.
- No two parts overlap by 0.15 mm or more.
These are the checks in parts/check.py, which fails the build when one fails.
What is not checked yet
Bought parts are drawn here as stand-in envelopes from maker drawings, not as CAD models of the real part, and some sizes are marked MEASURE until a real part is in hand. A first print and fit round with real parts: Coming next