Tools & Trades History Society

Mystery Tools

Niagara grinder query

A query for the engineers here from Anthony Evans. 

Do you know if the bushing and flange of this Niagara hand-cranked grinder can be removed? I bought a hand grinder recently with a view to fitting a modern grinding wheel to it. The bushing and flange currently attached to the arbor is skewed, so I think it needs to be replaced. All the other parts of the grinder (case screws, crank arm, wheel nut, etc) have all been removed with minimal effort but the bushing and flange aren't coming away at all. I'm unsure if they are designed to be removed from the arbor. The arbor is 5/8" where the threaded section is. The gear side is wider. The flange is attached to the bushing and the bushing itself is like a hollow cup that is attached to the arbor near the threaded section and floats over the arbor towards the gear section. All I've done so far is spray WD-40 between the bushing and the flange and apply some gentle taps on the arbor thinking that the flange and bushing will slide off towards the screw side (away from the gear and the case). But there wasn't any movement, so I stopped and thought I'd ask for advice before applying anymore force. Please find attached several images that try to show how the bushing and flange is attached to the arbor. N.B. I can't find any evidence of welding or soldering between the arbor and bushing. Any advice you could give me on how to remove the bushing (or even if it can be removed) will be gratefully received.

wheelarbor bushing flange plan