Changing Wheels on a buffer/grinder.

[RonBiffle]

What is the proper technique for changing wheels on a buffer/grinder. Some have a flat spot on the shank for holding with a wrench, but how do you correctly do it on a machine without a way of holding the shank ....... don't like using vise grips!
Ron

[mrpeter]

Some have a hole to put a bar in which then locks the shaft or may I suggest a screwdriver to lock it in place . If all else fails then you can only hold the stone itself or buffer whilst tightening ensuring that the machine is switched off. It is surprising how tight you can fix the wheels by just holding the stone.