Serious Education ... plus the most fun you can have in metal finishing.
Re-Finishing Zinc Pot Metal replica guns
An ongoing discussion from 2003 through 2015 . . .(2003)
Q. I collect Japanese replica gun models from the 1960's - 1980's which were made (I believe) using zinc or what they also term as "pot metal"...
Many of the replicas are in bad shape and need to be refinished and I'm wondering if anyone can give a suggestion on how to treat the zinc to give it that original "gun blue" look without simply painting them.
On real firearms blueing liquid is used which actually corrodes the metal to darken it however I'm told that this technique won't work on zinc because it's a non-ferrous metal.
I and my collection would be extremely grateful for any and all suggestions.
- New York, New York
A. I don't know much about gunmetal finishing but I know from a friend that for your application electroless will work fine. Notice, I'd like to know about all these methods (bluing, blacking, parkerising, etc.) by following your dialogs.
Good luck.Ahmad Semir Bizri
A. Regarding finishing replica guns. I too was told that gun-blueing liquids and creams do not work on non-ferrous metals. Most of these replicas are made from a frangible zinc alloy, most notably mazak. I had a poorly finished Thompson SMG replica that had a factory finish that looked like licorice. It just didn't look right. After disassembling it, I removed the toffee-like black and polished the metal (it took a long time). I degreased the whole thing and placed all parts in really hot water. I removed the parts one by one and dried them with paper towels and hair dryer to retain the heat. I then applied a cold blue liquid (any will do) with wads of cotton wool (I wore rubber protective gloves [linked by editor to product info at Amazon] ). I obtained a finish that I considered better than the original. Try it, what have you got to lose apart from about $8. I had tried cold blueing on cold replicas but the zinc alloy took better when hot.Jan Saunders-Singer
jeep tours - Minehead, Somerset, England
December 2, 2009
A. The heat method definitely works. I tried it a few days ago and it's definitely the key to bluing pot metal. Has to be clean, polished, put into boiled water; dry it. Get a hair dryer to keep it hot, then coat it with bluing agent -- a small paint brush is best, and put plenty on! Work it in and recoat. Keep the heat on, into hot water (helps the process), gently brush it down while it is under water -- and it should be ready to polish! Have done three non-guns with this method and it is the only way, so good luck.jamie round
refinishers. - gloucestershire, U.K.
January 8, 2015
A. Wire wool down the surface and use 'Birchwood Casey Perma Blue' =>
It's a cold bluing process that will, after removing the factory protection metal coating, turn the cast or pot metal black just like a real firearm. We treated four Denix replica Winchester rifles and they look exactly like the real thing. You may need one or two coats depending on how dark you want it.
Rigar - Glasgow Scotland UK
October 27, 2016
Q. I'm interested in bluing some pot metal Japanese model replicas, but it has a gold, bright finish. Does anybody know of a technique that strips the plating from pot metal substrates?Curt Aumiller
- San Jose, California, US
A. Hi Curt. I guess there are three obvious ways of removing a finish, namely burning it off, abrading it off in some way, or chemically dissolving it. Burning it off doesn't sound do-able and, unfortunately, the question of how to chemically dissolve an unknown finish without dissolving the pot metal isn't answerable. We can hope that some reader is so familiar with these items that he is fairly certain what the finish probably is ... or you can try to figure it out yourself and then give us some further info. Good luck.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
October 27, 2016
Q. Thanks for the rapid response. I'm enclosing a picture to see if anybody has any idea on the type of plating I'm dealing with.
There's a small flat piece that I can use for testing. Thanks.Curt Aumiller [returning]
- San Jose, California, US
December 31, 2016
A. Hi, regarding the gold-finished pistol (Broomhandle Mauser) I think I would play safe and re-paint. I use a high temperature satin black spray, several light coats; and once fully dried I rub down with black lead grate polish to create a realistic metal appearance.Ed Church
Living Historian - Feltwell, Norfolk, UK.