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Wtk: Best Cold Blueing/parkerizing Formula


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#1 leid

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Posted 30 August 2004 - 08:34 AM

Hi guys,
What is the best cold blue formula and method of application for touchup of WW2 TSMG, BAR, & MP40 small parts and mags. Brownells lists "OXPHO-BLUE" and "DICROPAN T-4" as their toughest & best cold bluing formulas. Anybody have a preference between these 2 products or know of something better?
Also what is the best touchup formula for parkerized parts of the same vintage?
THANKS
Carey
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#2 john

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Posted 30 August 2004 - 09:54 PM

Hey Carey!
I've used both quite extensively and here's what I can tell you.

OXPHO BLUE works best on "in the white" finishes. It needs to be applied several times (coats) to achieve a really beep blue finish, but will come out looking more like hot blue than anything else I've seen. It works great for touching up scratches if you take care and don't slop it around too much. Feather it into the scratch with the broken end of a toothpick rubbing back and forth several times, then wipe. Oil, and let it sit awhile. Then degrease and go for coat #2, 3, 4, etc until the scratch disappears. It seems like a lot of farting around but with a little practice on some scratched mags, you can feel confident enough to tackle that scratch on the receiver!! wink.gif

DICHROPAN works best for quick touchups. It will give you a deep black color with a single application.....degrease and apply, rubbing around for a minute or so with a cotton swab (or a broken end of a toothpick), wipe and oil. That's it.
Some real hard steels (lotsa chrome, like early Bridgeport A.O. guns) will need a couple coats to blacken completely.
Dichropan also works really well for touching up scratches in gray or black phosphates (Parkerizing). For this simply degrease and if finish is black, apply until scratch is blackened completely. If finish is gray, apply quickly with a cotton swab and wipe off immediately. This will leave a gray finish in the scratch. You may have to hit it twice until you match the gray, and it won't fill in the scratch as phosphate will, but it will certainly make it real hard to see if one is not looking for it!!

Birchwood Casey makes Cold Blue that smells like same chemical as Oxpho Blue, but I've had a quart of each of the Brownells products for years. They never go bad and you'll have them when you need them.

Hope this helps and Good Luck!! smile.gif

john
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#3 leid

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Posted 31 August 2004 - 08:58 AM

Hi John,
Thanks for the info! I'll get both products and experiment with them.
Carey






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#4 JTinIN

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Posted 31 August 2004 - 09:22 AM

Brownells News Letter on Cold Blue

and a link to the catalog page for Brownells T4 Dicropan

Edited by JTinIN, 31 August 2004 - 09:23 AM.

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#5 leid

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Posted 31 August 2004 - 05:22 PM

Very useful info! I was curious about Formula 44/40.
THANKS
Carey
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#6 john

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Posted 01 September 2004 - 07:28 PM

I've tried 44/40 also. Seems to be basically the same mixture (based on smell and results) as Oxpho Blue.
I had a bottle that I used up before I bought the Oxpho.

If there is any difference, it MAYBE darkens metal just a wee bit faster than Oxpho?? (Might take a coat or two less??) but it's been 15 some odd years since I used it last.... huh.gif

Seems to me that I saw it recently at a show and it was over 6 bucks for a 2 ounce bottle. The last bottle of Oxpho Blue I bought was a full pint for around $11.00.....

Depends on how much blueing you need to do, but it's nice to have around. I scratch a mag, it takes me 15 seconds to make the scratch disappear. wink.gif

Hope this all helps!

john
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