quote{This is a real gray area for safety !! }
Nah, its gonna be a Red area soon.....
Hell, never take a guard off a grinder & never use a disc thats too big for the grinder, the centrifugal forces are pretty big & add up exponentially with a too large a disc.
Also, as you noted the gyroscopic forces add up pretty quickly, the revs are far too high.
That & no guard is asking for a accident, grinder disc accidents are really bad, they never heal well & leave a lot of scar tissue.
I make use of the guard as a lever so I can maintain a steady pressure on the grinders motor.
You can use worn down discs on a smaller grinder, ie a 9 inch disc thats been worn down to 5 inches in a 5 inch grinder is Ok.
Actually I have a small mark on my 9 inch grinders guard. So that when its won down to that mark I take it off & put it on the 5 inch dia grinder disc stack on the wall, on a nail.
The disc is most efficient at its top revs, so let the grinder get up to top speed before touching the disc to the work peice.
I think the OP's found disc may be a worn down asphalt slitter disc. Or for stainless steel. They work real well.
Bookmarks