Phenolic is a thermoset plastic and is made by applying heat and pressure to layers of paper or fabric impregnated with a special synthetic resin. Phenolic is an exceptionally versatile material since it is lightweight, dense, strong and moisture resistant. One of the most common uses are black pick guards as used on vintage and re-issue Telecasters. I like spraying lacquer on the re-issue pick guards to make them look like the real thing. There are several types of Phenolic and each have different applications.

Paper Base: General purpose electrical grade. Used as panels for switchboards and instruments, for circuit breaker arms, and many other electrical applications. Best for all around use. Good machinability. I use this a lot for making bobbin prototypes, fixtures and bobbin assembly jigs. This comes in a variety of grades and surfaces.

Linen Base: Best electrical and mechanical properties combined. Excellent moisture resistance, superior machinability. Used as terminal blocks, panels and high humidity applications. This is good for making body templates and jigs.

Canvas Base: Tough with excellent impact strength. Used for prototype bobbins and routing templates. Has a wide variety of mechanical applications and good machinability.

Glass Epoxy: Has the highest temperature grade with outstanding mechanical, physical and electrical properties. This material works well for jigs and fixtures but it pretty expensive when compared to paper but machines well.

Phenolic comes in rods and sheets. The Phenolic rod can be used for side dots on a guitar neck and sheets can be punched out to make position markers on fingerboards. I have used Phenolic for all kinds of pickup applications. It is easily machined, threaded, drilled and tapped using standard tools.