I don't know how bad a key covered in soot is for a lock, but WOW can you see the marks. The little scratches in the key look like brass colored LED lights against a black velvet background. Unfortunately, its a real PITA.
Soot the key
Slowly insert key
Run file over shiny parts
Repeat until madness sets in or lock opens.
I think the magnifying glass will speed things up.
Theortically, I'm only putting a small amount of soot on the key pins (and then only the point). But the soot is actually greasy and I don't know how damaging it would be. It's a crappy practice lock, just curious if this is worse for the lock than I would think.
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