Today I went to buy a file---and---man---

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Does anyone have a comment on, or experience with, the old technique of sharpening files by soaking then in acid? I seem to recall it was phosphoric. I have never tried it myself. At today's prices, it might be worth looking into. Years ago I bought files from the Boeing surplus store. they appeared to have had this treatment, a dull grey surface finish.
My grandfather used vinegar to sharpen files I also use vinegar.
I think Phosphoric acid will work faster. It also produces rust. I leave a file in 20% vinegar for 8 hours. Household vinegar is
5% but still should work even if it takes longer.
mike
 

OrangeAlpine

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Does anyone have a comment on, or experience with, the old technique of sharpening files by soaking then in acid? I seem to recall it was phosphoric. I have never tried it myself. At today's prices, it might be worth looking into. Years ago I bought files from the Boeing surplus store. they appeared to have had this treatment, a dull grey surface finish.
Never tried it, but the preferred acid is sulfuric. Quicker acting and does not have the fumes of muratic.

My favorite file is labeled "farmer". It is flat and square, no taper at all. One side is coarse, the other is medium fine. Handle is shaped from the files parent material. Very handy to have laying around the shop, as it is often all that is required of the job at hand.
Bill
 

Brian Rupnow

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Inflight--I live in Ontario, Canada. The shipping back and forth to California costs more than new files do.---Brian
 

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