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An Important Note about spindle sizes and
grinding wheel bushes

Please read carefully before selecting wheel bushes to suit your grinder/wheel combination

Many manufacturers appear to try to 'simplify' the dimensions of grinder spindles when printing their packaging and instruction manuals. This is both patronising to users, who are treated as technical incompetents, and potentially dangerous. Chinese manufacturers are particularly prone to this errant behaviour and their errors are rarely corrected by the irresponsible manufacturers who purchase their products and brand them as their own, usually British, products.

Most 6 inch (150mm) wheel diameter grinders have 1/2 inch diameter shafts. Most 8 inch (200mm) wheel diameter grinders have 5/8 inch diameter shafts. Unfortunately these dimensions are erroneously described by these irresponsible manufacturers as being 13mm and 16mm diameter respectively. These are NOT equivalent sizes:

1/2" = 12.7mm NOT 13mm
5/8" = 15.88mm NOT 16mm

Fitting an oversize bush is both potentially dangerous and will lead to poor grinder performance. The only way to be 100% sure of ordering the correct size of bush is to remove a wheel and to measure the shaft diameter accurately, using a micrometer (Or, at the very least, a high precision digital calliper capable of measuring to +/- 0.01mm). Near enough is definitely NOT good enough.

If in doubt, seek expert advice.

1997-2007 P. Hemsley.  The information on this website is the copyright property of Peter Hemsley.  Coeur du Bois and The ToolPost are trading styles of Peter Hemsley.  Whilst reasonable efforts are made to ensure the accuracy of information presented, no liability can be accepted for errors in this information nor for contingencies arising therefrom.  If you are inexperienced in any aspect of woodworking, we would strongly counsel that you take a course of formal instruction before commencing to practice