Checklist: export in millimeters, keep walls at least 1.2 mm thick, make sure the model is one closed solid, and send STEP if you have it, otherwise 3MF or STL.
Which file format to send
- STEP (.step, .stp): best for engineering parts. It keeps exact geometry and true circles.
- 3MF: a modern mesh format that keeps units and can carry colors.
- STL: the most common format. It has no units, so the size can come in wrong if it was exported in inches.
1. Check the units
The number one problem we see is a part that arrives 25.4 times too small or too big because it was drawn in inches and read as millimeters. After you upload, check the size shown on the order page against your drawing. If it is off, use the file units setting to fix it.
2. Keep walls thick enough
Walls thinner than about 1.2 mm can print weak or not at all. For parts that take force, 2 to 3 mm walls are a good start.
3. Make it one closed solid
Meshes with holes, flipped faces or overlapping bodies confuse slicing software. Most CAD programs export a clean solid by default. If you made the model in a sculpting app, run a repair or make-solid tool first.
4. Leave room for fits
If two printed parts go together, leave clearance. About 0.2 to 0.4 mm per side is typical. Holes also tend to print slightly small. Read designing 3D printed parts that fit.
5. Think about orientation and overhangs
We pick the print orientation, but it helps to know that steep overhangs need supports, which leave marks. Flat bottoms and 45 degree chamfers instead of flat ceilings print cleanest.
No CAD file at all?
That is fine. Send photos, a sketch or the broken part and we will model it. Design my part.
Ready to go? Upload your file and you will see the price and ship date before you pay.