A CNC machine cuts with rotating tools, and that simple fact shapes how parts should be designed. Features that ignore how a tool reaches and moves can be expensive or impossible to make.
Respect the tool
Internal corners cannot be perfectly sharp, because a round tool leaves a radius, so design internal corners with a fillet that suits a standard tool size. Avoid very deep, narrow pockets, since long thin tools flex and chatter.
Keep features accessible from sensible directions to limit the number of setups, as every re-fixturing adds cost.
- Add radii to internal corners rather than expecting sharp ones.
- Avoid deep, narrow cavities that need long, fragile tools.
- Keep wall thickness sensible so parts do not flex during cutting.
- Limit the number of faces that need machining where you can.
Design it with us
Send your drawings or model through and we will flag anything that will drive up cost, then suggest tweaks that keep your CNC part accurate and economical.