Nylon 6, also referred to as cast nylon or polyamide, is a polymer, thermoplastic resin. Typically, parts from cast nylon are produced by molding (casting), but in some cases, there is a need to machine this type of material. As a general rule, there are no problems in milling cast nylon, although at times difficulties may arise such as overheating, chip evacuation, and deformation of a part after machining due to the elasticity of cast nylon.
In milling, a typical initial cutting speed is estimated at 400-470 m/min. (1300-1550 sfm) for milling cutters with indexable inserts, and 450-530 m/min. (1480-1750 sfm) for solid carbide endmills and endmills with exchangeable carbide heads. Next, according to the results, the cutting speed can be increased up to 900-1000 m/min (2950-3300 sfm). The greater values may cause overheating, and therefore, are not recommended. Pinpointed air coolant, especially through a cutter body is highly recommended, if not to say necessary.