Cutting and machining of cured composites parts can be challenging.  Cured composites can wear cutting blades out very quickly.  They are also very dusty when cut without using cutting fluid.

Many of these problems can be eliminated with the proper equipment.  I found a very interesting video of a fiberglass-reinforced epoxy resin block being cut using a water-cooled ring saw.  This saw is called the Revolution XT and it uses new technology to get a relatively quick and clean cut without making dust.  It looks like it would also allow some good freehand movement to cut curves and angles in composites parts.