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the edge heats up a LOT faster than the part that you're holding will though. lots of people that are new to razor restores often don't realize this. (note the big amount of blue-lined razors on ebay)

belt..sander... dremel?
be EXTREMELY careful doing this not to heat up the blade. use a slow belt speed if you can regulate it, and regularly dunk the razor in water. you can't do it too often.
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