Damaged Parallel: Fix or Toss?

[JackF]

Spro, you got me again and I know I'm dense but what is dieing NF?



Jack.

[Frank Ford]

I assume it's a pun on cutting fine threads with a die and, you know, "croaking."
Spelling choice can be tricky with thinly stretched puns.

Now, if somebody could single-point the way outa here. . .

[JackF]

Yep, consider it done.

Jack.

P.S. Did I mention I was dense!!

[tornitore45]

The consensus here is that stoning hardened tools will remove a burr, yet remove less than a femto-inch from the base metal. I have considerable experience in filing and can attest to how laborious is to remove 0.001" with a smooth file on mild steel under precision filing.
(spent 5 years in trade school making object graded with 0.01mm comparators)
Obviously this does not apply when using a mill file.
So stone away without regrets.

[Marty Feldman]

These things are always a matter of the tolerances you want to hold. Stoning, by definition, removes metal. The same stoning operation can return a parallel to perfectly good service for one operation but not for another that requires very tight tolerances. If after stoning to reestablish what you like for flat, and then micing for parallelism, and if for the work you do you are satisfied with the reliability and degree of precision of your micrometer readout, then fine, keep the parallel. Personally, what I do isn't to watchmaker's standards of tolerance, and I stone parallels frequently.