Tormek Blackstone Silicon has been developed to shape and sharpen HSS and other high-alloy steel qualities. It can also sharpen carbide where the tool already has the correct shape. The SB-250 does not sharpen regular carbon steel faster than the Tormek Original grindstone.
The combination of the hardness, shape, and size of the grinding grains allows the stone to work efficiently at the low speeds of the Tormek machine. The stone's higher grinding ability is especially valuable when shaping tools with a large grinding surface, where the grinding pressure is low, e.g., machine planer blades and chisels for wood turning.
The grain size is 220, which is the same as on the Tormek Original grindstone. The stone can be adjusted to provide a surface equivalent to a 1000-grit stone, using the stone grader SP-650. Thanks to its sharp and relatively small grains, Blackstone Silicon grinds effectively even at low grinding pressures. Blackstone Silicon also has a very long lifespan.
Suitable for Tormek T-8, Tormek T-7, and previous Tormek models with a 250 mm stone.