Mounted Points are extensively used in the Investment Casting industry, other foundry applications, tool & die, general deburring applications, and many maintenance operations.

A mounted point is a grinding wheel that is permanently fastened to a steel mandrel. 

Mounted points are classified in groups . . . A, B & W.  “A” shapes are generally designed for offhand grinding, but may also be used in precision grinding applications.  “B” shaped mounted points are widely used throughout the Investment Casting industry, tool & die, etc.

All shapes can be found in our online catalog.  Hard copies are also available at no charge.

We supply a Safety Guide with each box of mounted points.  The maximum operating speed tables for A, B and W shapes with various overhangs are from the ANSI B7.1 Safe Guide for the Use, Care and Protection of Abrasive Wheels.  Copies of ANSI B7.1 may be ordered from the Unified Abrasive Manufacturers’ Association,

• Dimensions of the wheel
• Diameter of the mandrel
• Distance from support to base of wheel (Overhang)

Reducing the size of the wheel (diameter or thickness) will generally raise the maximum speed.  Increasing the diameter of the mandrel will raise the maximum speed.  Reducing the overhang will raise the maximum speed.

The maximum speed is not measurably affected by the type or style of machine used.  The condition of the machine spindle and bearings may modify the maximum speed.  Worn chucks and lack of care in mounting may result in run-out and cause mandrel failure or wheel breakage.  Check the collet or chuck and replace if necessary.  Run-out and out-of-balance of the wheel will decrease the maximum safe speed.

The maximum speed for the common wheel/overhang combination can be read directly from the tables in ANSI B7.1 or the Safety Guide we supply with each box of mounted points.  The speed for intermediate wheel/mandrel/overhang combinations not shown can be estimated accurately enough by interpolation.

Excessive work pressure may cause bending or fracture of the mandrel even at speeds below the maximum.  If the mounted point runs smoothly without load, but not under load, excessive pressure may be the cause.  With reduced pressure a softer wheel grading may be necessary.  If the problem persists a heavier mandrel may be necessary.

Mounted wheels on threaded mandrels usually have no overhang and the maximum speed is the same as for 1/2 inch overhang unthreaded mandrels of the same diameter.

Sandusky-Chicago Abrasive Wheel Co. has a solid reputation with Investment Casting mounted points, as we are the true “originator” in this field.