. Commstones should be twice as long as the width of the longest flat spot and as long as will work freely between adjacent brush sets.2 in X 1 in X 8 in, Grades F/P, Commstone, Pocket Combination When compared to turning tools commstones are easier to use, more time effective, and remove less copper.
Our Brush Seaters come in 5 grades: ES EX tra Soft, FH Fine Hard, MS Medium Soft-our most popular, FS Fine Soft, and MH Medium HardBrush Seaters are used to easily and accurately seat commutator and slip ring brushes of any material.