Hey everyone, I’ve been printing functional mechanical parts (brackets, enclosures, press-fit joints) for a hardware prototype, and dimensional accuracy has been the single biggest headache. I’m not talking about aesthetics; I mean parts that need to actually fit together.
After a lot of trial and error, I’ve noticed a few things that seem to matter more than I expected:
- Orientation matters a lot — the Z axis on SLA is far more accurate than XY on my setup. Orienting critical dimensions vertically has helped more than any slicer setting.
- Resin temperature is underrated — I didn’t pay attention to this early on. Printing in a cold workshop (~18°C) versus a temperature-controlled room (~24°C) made a measurable difference in shrinkage.
- Post-cure time affects final dimensions too — I’ve been over-curing and parts were coming out slightly smaller than expected.
Curious what others have found. Are there specific settings in PreForm or resin choices that have made a real difference for you? Especially for press-fit tolerances, I’m currently adding ~0.15mm clearance on all mating parts but would love to tighten that up.
Also interested if anyone has done systematic testing (printing calibration cubes, calipers, etc.) and has actual numbers to share rather than just intuition.