Profile: Kallen Engineering manufactures & supplies bit grinding systems. We supply specialized grinding pin equipment and accessories. Grind-o-matic grinding wheels overcome the problem of the zero grinding speed associated with grinding pins. The wheels are individually milled to the finest tolerance and surfaced with a specially selected grade of diamond to ensure a symmetrical grinding area. Using a grinding wheel to resurface a button produces a uniformed and exact shape that is ideal for grinding. These grinding wheels are available as hemispherical and ballistic matrixes in sizes 6mm to 16mm.