Machining Guide

Basic Machining Tips for Engineering Plastics

  • Keep heat to a minimum and ensure heat build-up in the part is avoided
  • Keep tools sharp at all times
  • Ensure that only the cutting edge contacts the material
  • Apply coolants (per guidelines) where heat is generated
  • The lower rigidity of plastics may require support or plugging to avoid deflection in thin walled sections
  • Cutting tools should be high speed steel or carbide tipped for production runs, especially on graphite or glass filled materials
  • Matching tolerances are much higher than for metals
  • Watch stress relieving where a large body of material is removed
  • Thermal conditioning may be required after pre-machining on some parts
  • Allow a tolerance of 0.1-0.2% of nominal size
  • Be aware of thermal expansion in larger parts or panels where fixings are required
  • Minimum tolerance for small dimensions 0.05mm

For more detailed information, Dotmar is pleased to provide comprehensive technical guides courtesy of our supplier Rochling.

Please contact your local Dotmar branch on 0800 650 750 for more information or assistance.