cutting & drilling of carbon and graphite composites

Cutting

Selection of the right tool is critical when cutting and drilling carbon and graphite fiber composites.
Diamond coated tools are the best choice, and carbide tools can be used as well. Steel tools are not recommended as these materials dull steel quickly.

Carbon fiber composites may be cut dry, but this produces a great deal of fine dust so that one should always wear a protective dust mask and use a dust-collecting vacuum. Ideally these materials should be cut wet, which controls the dust, and reduces heating of the tool and part.

Abrasive wheels may be used for cutting or surface grinding composites.

A high tool speed and slow feed rate are recommended, with multiple passes depending on the thickness of the composite.

Routers may be used with carbide bits, with high tool speed and low feed rates.

The feed rate should be adjusted slower for thicker composites depending on cut quality.

Drilling

The same principles apply to drilling as cutting.

Use a high tool speed and low feed rate.

Several drill designs specifically for drilling composites are available from different manufactures.

Solid carbide, brad-point drills work well.

Precautions

1. The dust from cutting carbon fiber composites is electrically conductive so all electrical device in the work area should be shielded and/or sealed.
2. One should always wear a protective dust mask and use a dust collecting vacuum when dry cutting composites
3. Skin contact with this dust may cause mechanical dermatitis so appropriate protective equipment should be worn, however, there are no other known health concerns.