Ribs and fillets: improve strength through geometry
A part does not need to be solid to become stiffer or stronger. Ribs can support thin walls efficiently, while fillets can reduce stress concentrations where geometry changes abruptly. For functional parts, better geometry is often more efficient than simply adding infill.
Why sharp inside corners are critical
At a sharp internal corner, geometry and load path change abruptly. This can create local stress concentration. A radius creates a smoother transition.
Where fillets are useful
- hook roots
- brackets
- handle transitions
- ribs
- screw bosses
- tabs
Ribs
A rib connects a loaded panel or arm to a supporting wall. It can:
- reduce bending
- increase stiffness
- use material efficiently
Do not make everything massive
Oversized ribs can waste material, increase print time and alter local shrinkage. Size geometry for the application.
- waste material
- increase print time
- alter local shrinkage
Keep printability in mind
Design ribs so that:
- overhangs remain manageable
- unnecessary support is avoided
- layer paths remain sensible