Este vídeo diz o seguinte:
Here's my Tonson TS-3040C CNC making an EFIS panel for my flight simulator. For the lettering I am using a 0.4mm End Mill and for cutting out I'm using a 1mm End Mill. RPM is 10000 and movement is 300mm / Min. The material is Cast Acrylic which I have given one coat of black paint and two coats of grey paint.
Então, isso é pelo menos um método, mas provavelmente há mais ...