Choosing the Right Bit A 1/4-inch solid carbide O-flute is a great choice for cutting because it has an up-score that will pull out the chips as the cutting occurs. It prevents plastic chips from building up inside the curve of the cut. If you want to engrave acrylic, a 60° engraving bit is perfect for V-carving.

Engraving and milling Plexiglass / acrylic with a CNC Plexiglass has a low melting point of around 80 degrees Celsius, or 175 Fahrenheit. So, it is a good idea to use a minimal lubrication system (mist cooling unit) to avoid the material melting. That way you get better edge quality and extended tool life.