Bench Grinders

Bench grinders are found in almost every shop. When the gaps aren’t set right, work gets pulled between the wheel and the rest, and wheels can shatter.

• General Industry
• Construction

Set-up requirements

• Work rest: no more than 1/8 inch from the wheel
• Tongue guard (adjustable upper guard): no more than 1/4 inch from the wheel
• Side guards cover the spindle, nut and flange
• Grinder bolted to the bench or stand
• Wheel RPM rating equal to or higher than the grinder’s speed
• Eye shields in place (and still wear safety glasses plus a face shield)

Readjust the gaps as the wheel wears down.

Ring test before mounting a new wheel

Tap a clean, dry vitrified wheel lightly with a non-metallic object (like a screwdriver handle). A good wheel gives a clear ring. A dull thud means it may be cracked. Don’t use it.

Using the grinder

• Stand to the side when starting it and let it run for about a minute.
• Grind on the face of the wheel, not the side (unless the wheel is designed for it).
• Hold small parts with locking pliers or a holder.
• Dress the wheel when it’s glazed or out of round.

• Don’t wear gloves near the wheel (wire wheels especially). They can get caught.
• Don’t grind aluminum or other soft metals on a wheel meant for steel. It loads the wheel and can make it burst.

Last updated: October 2, 2026