A model that looks perfect on screen can still print badly. These rules cover most of the problems we fix before printing.
The rules of thumb
- Walls: at least 1.2 mm thick (three nozzle widths). 2 mm or more for parts that take load.
- Overhangs: up to about 45° prints without support. Steeper faces need supports, which leave marks.
- Bridges: short flat spans between two points print cleanly; long ones sag.
- Clearance: leave 0.2–0.3 mm between parts that slide or snap together, more for print-in-place hinges.
- Holes: small holes print slightly undersize; design them 0.2 mm larger or drill them out.
- Text: raised or engraved text should be at least about 5 mm tall and 0.6 mm deep to read clearly.
Orientation decides strength
FDM parts are weakest between layers. A hook printed lying on its side is much stronger than one printed standing up, because the load runs along the layers rather than prying them apart. We choose the orientation for you, but it helps to tell us where the force goes.
Layer height
0.2 mm is the everyday standard. Finer layers (around 0.08–0.12 mm) look smoother on figures and curved surfaces but take two to three times longer.
Common questions
Can you check my design before printing?
Yes. We review every file and tell you if something is likely to fail, with a suggested fix.
What software should I use?
Tinkercad is free and easy for simple shapes. Fusion and Onshape suit mechanical parts. Blender suits organic shapes.