I have a bunch of Nicholsons for steel work, I have a bunch of Simmonds that I got a great deal on a box of, they are case hardened crap that bends and dulls quickly, but not as quickly as the Sears Craftsman files, I have a bunch of Sears Craftsman files that I use for filing tang shoulders square against file guides, when they dull on all usable sides I throw them in a box to take back to the store next time I drive by. They are such unimaginable crap that they will dull on mild steel, but Sears exchanges them so I have a pile that just gets rotated. For jewelry work I use Grobet, Valitan, and a german brand that I forget, but those are very fine cut and the Nicholsons work great for steel
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