King Arthur’s Tools claims that being able to see what you’re sanding means you’ll work faster because you don’t have to keep removing the tool to see your progress. With their Holey Galahad carving discs, you can actually see through the disc to the surface you’re cutting. The discs can be used on wood, fiberglass, plastic, foam core, soapstone, and other materials.
Made in the USA, the discs will fit most 4-1/2″ and 125mm angle grinders — just be sure to keep the speed under 14,000RPM. The 4″ diameter steel discs have sharp conical tungsten carbide teeth bonded over the cutting surface and can be used on both the face and the edge
King Arthur’s Tools sells six different varieties of Holey Galahad discs: flat or round profile in coarse (90-grit), medium (70-grit), or fine (SSG390). The fine discs cost $70 and the coarse and medium discs run $80. Their universal hex nut may be required to work with their grinder; that’ll run you another $8.