How to Change Discs On a Rotary Grinder. You can find many types of rotary grinders on the market. All grinders have the capability of using different discs for different types of jobs and material. If you own a rotary grinder, it's a good idea to learn to change the discs on the rotary grinder before you find yourself in the middle of a job with no time to waste.
Check the grinder before you begin. The newer discs on rotary grinders have patented buttons that allow you to remove the disc without any tools. You may have one like that. In models like this, there's usually a spot to depress and then remove the disc.
Turn off the grinder before you attempt to remove and change the disc on your rotary grinder. If it's battery powered, put the grinder in lock position so you can't accidentally turn it on. If it's electric, unplug the grinder from the wall.
Look for a nut in the center of the disc. This is a give away that you need to use additional tools. Sometimes the grinder comes with a tool necessary to loosen and remove the nut. Other times you need to use a wrench.
Lock the wheel into place before you begin. You can find a button or switch at the side or back that allows you to do that. When you lock the wheel in place, the disc remains still as you loosen the nut in the center.
Remove the nut in the center with either the tool provided with the grinder or a shop tool and lift the disc off your rotary grinder.
Lift the disc off the rotary grinder. If you have different discs, remember to check for the best fit. Put the nut back on a different way for different discs. Check for a rim and indentation on one side of the nut and a flat side on the other. A visual inspection of the disc for the rotary grinder gives you information about the side to use.