Machining composites can be a difficult process. Unlike metal, where the grade and properties are standard and well known, composite materials are extremely different from one another.
For example, different fiber reinforcement and resins have different abilities to be machined. A carbon fiber composite will require different tools and machining feed speeds then a fiberglass composite.
Additionally, the orientation of the fiber and the manufacturing process of the composte will also effect the ability to be machined. Incorrect tools or methods can cause the composite to splinter or delaminate.
Machining and drilling composites is generally considered a grinding process, instead of a cutting process. For this reason, diamond coated machine tools and bits are used to abrasively remove material. Most commonly, water is used in conjunction to cool and prevent overheating in this frictional cutting of the composite.
Machining composites is a trial and error process. By optimizing speeds, clean cuts and holes can be produced. Additionally, talking to a tool manufacturer can provide a great deal of insight. They often have years of experience and are willing to pass on this knowledge.
