A great guide to CAD/CAM by lcamtuf. Includes advice on choosing and setting up a CNC mill, CAD, resin casting, mold making, work safety and many other things. I especially liked the existential CAD advice section, but there’s many great information throughout.

Here are a few images of parts lcamtuf made for a robot.

CNC-machined master, a negative mold made out of silicone, and the final parts:

All parts:

One of the wheels on a chassis:

via @jprogers