Methods For Making Holes And Cutouts In Non-metallic Enclosures
There is a range of nonmetallic materials, just as there is a range of metals. Cutting, milling, drilling, tapping, machining, sanding of polycarbonate, fiberglass and acrylic have individual nuance, just as steel, aluminum, stainless each have individual machining considerations.
This page is not a tutorial on machining techniques. The intent is to draw attention to the differences in non-metallic material surfaces and why there is not a singular technique that works universally on all materials
Generally speaking, the ability to accurately drill holes or machine any material starts with sharpened bits, cutters & blades, as well as the user’s skill and patience. Polycarbonate is an easier material to work with because it is a uniform build-up of resin to form a pre-determined thickness. By contrast, fiberglass is a complex material made up of random glass strands in a polyester resin. The random complexity is a strength factor but it affects the way a cutting tool or drill bit passes through it.
The ability to accurately drill holes in composite fiberglass material has been the subject of numerous articles and how-to demonstrations. Composites offer the benefits of part integration and minimization along with substantial savings in weight. Along with this is a reduction in the requirements for machining operations that need to be performed to complete an assembly. However all drilling and cutting operations cannot be avoided completely in most cases. Most of these operations are similar to metal removal techniques but there are some differences that need to be addressed in order to make clean, high quality holes and cutouts in composites.