Glass fibre pencil

A glass fibre pencil is abrasive and is mainly used to sand surfaces were you can't use sand paper. Again in tight spaces or where good control is needed. It does excellent service when removing superfluous soldering material. Glass fibre is brittle and it breaks off during operation. Make sure you wear safety goggles when working with it. Also the broken off fibres can be very nasty when they penetrate your skin.