Thread: Restoring with minimum loss

It's difficult to know the exact situation without seeing pictures, but do you mean there is engraving or gilding on the large surfaces of the blade? Adhesive tape can protect these pretty well, so that you use a polishing compound around them.

There is a self-adhesive copper tape sold for making reproduction Tiffany-style lampshades. It is common in many sizes on eBay. As it is meant to be stuck around panels of glass and soft-soldered together to imitate leaded panes, it clearly can't fall off at the first traces of frictional heat.