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Formula for Zinc Parkerizing

March 25, 2009

I have looked for details about zinc parkerizing on the web, but unfortunately, even though there is a lot of hints, the technical nitty gritty is missing.
What I am looking for is a real formula naming specific chemicals ( and not drain-cleaners, automobile products, and "XX" jello, cat litter de-hydrator or whatever.

I understand that the chemistry involved should be rather elementary ( zinc phosphate /Fe) , but the devil is usually in the details; Do you start out with adding zinc metal to Phosphoric acid solution or with manganese phosphate ?

I am also particularly interested in the post parkerizing, passivation and sealing process;
Here, I saw mention of "Chromatizing", and wondered if this involved Chromic acid pickling.

It would be neat to settle the question of formula, temperatures etc in a nice definitive, scientific kind of manner, if only to avoid messing with jello and catlitter :-)

I look forward with thanks in advance for your kind, expert assistance.

Vincent Borg
Gunsmithing - Malta Europe

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My best advice is to use a commercial product. There's lots of little tricks used in making commercial products that will make your life easier.

If you're dead set on brewing your own, check out "The Chemical Formulary." It's a series of volumes (I think they're up to about 40 by now) containing public domain formulas for just about everything, including what you're looking for.

I do not think you will have much luck on the web. This kind of information doesn't tend to be very accessible on line.

Dave Wichern
Consultant - The Bronx, New York
May 17, 2009

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May 22, 2009

Exact description of process is in old Angiers book Firearm Blueing and Browning [on eBay , Amazon, AbeBooks] (10-20$+postage).Hope it helps and good luck!

Goran Budija
- Cerovski vrh Croatia