Using an engraver to remove hardened rust?

[EFG]

Has anyone ever tried using an engraver to remove the hardened rust that electrolysis won't remove? I'm talking about the really stubborn black crust that's left over and has to be taken off mechanically. It's mentioned in the metal detecting world article on electrolysis but searches don't reveal it being done anywhere else. I'm wondering if anyone uses this method and could tell me what machine and tips to get, technique to use, etc?

Many thanks.

[Danmark]

What is the item you are trying to restore? .... you dont want to use a sledgehammer to crack an egg ( as it were)

[Grimebox]

I would suggest that an engraver would damage the surface of the metal. By its very design its meant to make a mark in whatever it’s pressed against

[BlackCat1982]

If electrolysis hasn’t worked then you could try oxalic acid or white vinegar. An engraver or dentist drill might be a bit extreme as already said.

[GlennAgain]

I suggest a Dremel with a Sanding-Wheel...

[EFG]

What is the item you are trying to restore? .... you dont want to use a sledgehammer to crack an egg ( as it were)

A ground dug F1, so nothing fancy and already quite rough. I've been using steel picks to try to remove some but it's time consuming. I then use a copper scourer to try to remove any remaining crust. This process has been fairly effective but not perfect. There's a bucket load of other assorted bits in bad to fair condition to be done this summer so looking to save time as well as some local history.