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Aye.

So you'd have to go slow, and alternate the sides a lot in order to wear down boths sides with the same amount. It won't be a trivial task. I just wanted to indicate that it is possible.

Actually, you can grind blades like this on a belt grinder.
Once you have the primary hollow, you switch to a contact wheel with a smaller radius, and make it more hollow.

It is not as easy...