On Fri, 11 May 2012 12:15:50 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

I've been learning on the Darex E90.

The stone I received was an aluminum oxide cup, and the type 11 cups they
use are cheap in Al2O3 (about $30 for the same size and rim thickness as
the Darex stock wheel).
LLoyd

What size grit and what letter of hardness do they use in their
aluminum oxide wheels?