Mounted points are small abrasive heads on a steel shank, used in die grinders and flexible shaft tools for grinding in locations a full-size wheel cannot reach: inside tubes, in corners, in slots and on castings.
Head shape follows the geometry of the work — cylindrical for flat and edge work, ball for concave surfaces and holes, tree for radii and confined areas, cone and inverted cone for angled edges and back-side work, and taper for narrow slots.
Abrasive type and grade must match the material. Aluminium oxide in a range of grades covers general steel work; silicon carbide is used for cast iron, non-ferrous and carbide; zirconia and ceramic grades cut faster on stainless and hard alloys. Softer grades are used on hard materials and harder grades on soft materials — the reverse of what most people expect, because a soft grade on hard material keeps fresh grain exposed.
Shank diameter and length must match the tool and the reach. 1/4 in shanks fit standard die grinders; 1/8 in shanks fit pencil grinders. Speed rating matters — mounted points run at high RPM and a point rated below the tool speed can burst.
