Plastic Turning Machining Guidelines

Turned plastic parts are held in place on a lathe and rotated against a cutting tool

turning diagramTurning 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 best practices 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.

For more information, view the turning information below for each performance plastic.

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 PLASTIC MACHINING METHODS

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