Hi Gene,
Sorry for the late answer, and merry Christmas to you all – while I still remember it

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I don’t know if it is a Dremel 511, on the thing is says Dremel Multi, so I suppose that is what it is

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I used abrasive buffs fine 512 S – but before you start I would recommend that you get a handful of these abrasive buffs as the steel is very hard, and the buffs relatively soft in order not to scratch the blade.
Jens
PS I have not read all the mails, so should I have answered the question, the merry Christmas still stands.