The "other" grinder blade.

Originally Posted by Bear

I've been trying to find cutoff blades for my little grinder. Thought it was a 4 1/2" grinder (7/8" arbor), but turns out it's only a 4" (5/8" arbor), so I finally got the right size blades to use, but!, when I started to put one on ( they're thinner than the grinding wheel that goes on it), the chuck won't tighten all the way to grab it (stops about the time it would grab the thicker grinding wheel) leaving the thin cutoff wheel loose. Now I'll have to get some 5/8" washers to fill up the space so it will snug up to the blade.

Take another look at the "bushing" the wheel would tighten against. Does it come off? I had the same issue you're having and it's designed to flip it around to use with a thin blade.