Evidently, I screwed up in a first attempt at sharpening a chisel. The 3/4"
chisel had a good 1/16" missing from the corner. I switched to an much more
agressive grit after 10+ minutes of not-much-progress at 220.

The nick is gone, but now I've got and put a radius over the width of the
tip. It drops off by about a 1/32".

I don't have a grinder (maybe this is why the Lord invented Harbor
Freight?) - and have two questions:
a) How did I put the radius on there? Was I inadvertently applying to much
pressure to one side? A sort of roll effect as I was sharpening?
b) How do I get it out?

Thank you!