Turning Guidelines Turning is a common method for machining plastics. In this process, a plastic piece is held in place on a lathe and rotated against a cutting tool. Below are guidelines for turning several performance plastics. Fine, C-2 grade carbide inserts are recommended for turning. Polished top surfaces will help to reduce material build-up, allowing for better surface finishes. Cutting edges should have generous relief angles and negative back rake to minimize any rubbing action. Rough cuts should be run at a feed rate of 0.015 IPR and finish cuts should be run at a feed rate of 0.005 IPR or less. See our Plastic Machining Guidelines for more information. Need help turning plastic? Ask a Plastics Expert. Special Measures: █ Preheat material to 250°F █ Caution when using coolants, susceptible to stress cracking █ Use carbide-tipped tools The nose radius r must be at least 0.5mm Material α Clearance Angle (°) ϒ Rake Angle (°) X Side Angle (°) V Cutting Speed (ft/min) S Feed (mils/rev) ABS 5 - 15 25 - 30 15 650 - 1640 0.008 - 0.020 Acetal (copolymer) 6 - 8 0 - 5 45 - 60 980 - 1960 0.004 - 0.015 Acetal (homopolymer) 6 - 8 0 - 5 45 - 60 980 - 1960 0.004 - 0.015 Noryl 5 - 10 6 - 8 45 - 60 980 0.004 - 0.020 Nylon 6 6 - 10 0 - 5 45 - 60 920 - 1640 0.004 - 0.020 PAI 2 - 5 0 - 5 7 - 10 320 - 390 0.002 - 0.003 PBT 5 - 10 0 - 5 45 - 60 980 - 1300 0.008 - 0.015 PEEK 6 - 8 0 - 5 45 - 60 920 - 1640 0.004 - 0.020 PET 5 - 10 0 - 5 45 - 60 980 - 1300 0.008 - 0.015 Polycarbonate 5 - 10 6 - 8 45 - 60 980 0.004 - 0.020 Polyethylene 6 - 10 0 - 5 45 - 60 920 - 1640 0.004 - 0.20 Polyproylene (homopolymer) 6 - 10 0 - 5 45 - 60 920 - 1640 0.004 - 0.020 Polysulfone 6 0 45 - 60 1140 - 1300 0.004 - 0.012 PPS 6 - 8 0 - 5 45 - 60 920 - 1640 0.004 - 0.020 PTFE 10 5 - 8 10 490 - 1640 0.004 - 0.012 PVDF 10 5 - 8 10 490 - 1640 0.004 - 0.012 PPSU (Radel® R) 6 0 45 - 60 1140 - 1300 0.004 - 0.012 Ultem® 6 0 45 - 60 1140 - 1300 0.004 - 0.012 DuPont™ Vespel® Polyimide 2 - 5 0 - 5 7 - 10 320 - 390 0.0200 - 0.010 Explore Other Machining Methods Plastic Milling Machining Guidelines Both CNC and manual mills are used for plastics. Review guidelines for milling several performance plastics. Plastic Drilling Machining Guidelines Machining guidelines to help avoid breaking, tearing, overheating, or dimensional deviations when drilling plastic parts. Plastic Sawing Machining Guidelines Machining guidelines for cutting plastic parts using multi-axis CNC saws, band saws, or circular saws.