Conventional Machining Principles
Apply to Composites.

Call us for information on tooling specifications for machining composites.

Complete Machining to Precise Specifications

Most of the composite structures manufactured by Amalga Composites are machined to final engineering tolerances. Our machining capabilities allow us to deliver your part finished and ready to assemble – whether you need piston lead-in chamfers, milled snap ring grooves or other secondary machining. Ask us for a competitive quotation.

Beveling & Drilling

Depending on the size of the production run, cut-offs are beveled with hand files, shape block sander or an 8,000 rpm air motor equipped with a carbide burr.

Grinding, Milling and Turning

Standard metal-working lathes and milling machines are sufficient for machining thermoset composites. High-speed steel tools can be used if their sharpness is maintained, but carbide or diamond-tipped tools will be more economical on large production runs. Composite structures can be finished to close tolerances by sanding and/or grinding.


Fiberglass-reinforced thermoset composites can be cut with hand saws, band saws and circular saws.

Critical Production Details

At Amalga, we are proud to offer the very best finishing to complete your project, including: beveling, drilling, cutting, custom paint, grinding, milling and turning. We are experienced and skilled, but also recognize some companies prefer to finish their product in-house. In order to maintain the quality of each product we manufacture, we suggest the following: 

  • The best results are achieved using Forstner drill bits designed for composites.
  • Drill bits with specific helix angles, wide-polished flutes and point angle for fiberglass-reinforced thermosets limits chip packing and overheating.
  • Helix angles of 10 to 50 degrees, clearance of 9 to 20 degrees and point angles of 60 to 120 degrees are required.
  • Vary drill speed with the size and depth of hole.
  • Carbide and diamond-tipped tools will produce a smoother finish and are more responsive when operating at higher speeds and slower feeds.
  • A bit that is approximately .002″ oversize is recommended.
  • Support the backside of laminate with wood or plastic to prevent delamination and splintering.