On Sat, 02 Mar 2013 18:16:51 -0500, BQ340
wrote:

On 3/1/2013 8:56 AM, Ed Huntress wrote:


Nitric is much better for sharpening files. Yes, I've used both.
Nitric takes a faster bite, and seems to be less inclined to
preferentially round the cutting edge. It bites everywhere.

I hate having nitric anywhere in my house. I keep it in the garage.


They will be sharper after an acid bath, but they won't cut flat anymore.

MikeB

Right. It's a last-ditch procedure to give them a little more life for
rough work.

I haven't done it for 30 years, since I inherited a pile of new,
unused files.

--
Ed Huntress