Touching up a Charcoal Blue finish?

[Revolvr]

Hi all,

Is there any cold blue solution available I can use to touch up the Charcola Blue finish on a Cimarron piece? This is a lighter blue than I have seen any cold blue available for. My model P has quite a bit of wear along the backstrap and trigger guard.

Alternatively does Cimarron or someone else offer re-bluing services?

Thanks,

-- Clay

[Virginia Gentleman]

What Cimarron and Uberti call Charcoal Blue is really Nitre or Fire Blue which is done by heating Potassium Nitrate salts until molten at 600F then putting the polished parts in the salts until they reach the right color.  The parts are then rinsed with very hot water, dried and oiled before being put onto the gun.  It is a very fragile finish and I think you will make it look worse by trying to touch it up with cold blue.  You could try it, but you might not like the results.  If you are going to get it re blued, I would recommend for durability going with hot blue, but if you want the Nitre Blue restored, Ford's Custom is the only place I know that will Nitre Blue large parts like barrels and back straps. It is more expensive than regular hot blue too.  Other options you might consider are Belgian or Rust blue as they look more like 19th century blue than modern hot blue, but again they are more expensive.  You could also just let the gun wear and age so it will start to look old.

[Big Hext]

Howdy,

That finish is designed to wear into a patina.. so if you're not crazy about the look, you might want to trade with someone who is looking for a gun that will age.  Different courses for horses, ain't nobody wrong.

Adios,

[Revolvr]

Thanks for your replies. I get the picture now.

The patina around the trigger guard and the backstrap actually looks good, except for one thing. As the finish wears it turns dark brown just before the metal shows through. On one place there is a fingerprint embedded in the remains of the finish. I guess eventually it will go away, but I was suprised to see this finish was so suceptable to oils in your hand.

The other area I wanted to touch up was some scratches on the top of the backstrap and on top of the barrel. Guess I'll let it wear naturally. Overall I'm pleased with the looks. The other wear points are where one would expect from a holster.

Final question though, how authentic is this nitrite finish? Was it actually used at the time?

thx

-- Clay

[Virginia Gentleman]

Nitre bluing did exist in the 19th century, but usually as a decorative finish for small parts as it is used today. 

[Revolvr]

I have a book "Colt an American Legend" by R. L. Wilson. Long on large color photographs of Colts most of us will only drool over, but short on text.

Anyway, many of the color photos appear to show the trigger and 3 frame screws as a brighter blue than anything else. Looks like the small parts were often blued with this method.

-- Clay

[Virginia Gentleman]

Clay, it wouldn't surprise me that some of the smaller parts may have been nitre blued since it is such a quick and easy process if set up to do it.  Charcoal or rust bluing back then as it is now is a more time consuming process.  BTW, hot salt blue, the modern process was started by Mauser Waffenfabrik in 1931, but did not catch on in the United States until the late 1930s with Dulite Bluing salts first marketed then, with Winchester being one of the first to use it.

[Dakota Widowmaker]

I have found one product that matches the charcoal bluing quite nicely.

http://www.bluewonder.us/

[Virginia Gentleman]

I would try a small area that is in the white and see how it matches.  The Blue Wonder I saw in person looked more like a blue/black than a fire blue, but if it works go for it.

[Revolvr]

I sent Cimarron an e-mail asking this, and they sent the following:

"you can touch up by using brownells dicropan t-4 touchup
its not perfect but looks better than the scratch"

I think Dicropan is much darker too so I'm a bit skeptical.

-- Clay

[Trooper Lennox]

Howdy'

Read your question about charcoal blue.  I'll give you a method that I have used for years.  It's easy to use on triggerguards and backstraps, but more difficult to use on barrels, as you will understand after I've described it to you.  I read about it in American Rifleman back in the 60's.  It's the same method that Springfield Armory (the original Springfield Armory) used back in the late 1800's.

The part that you want to blue is removed from the gun and degreased.  Then you rub a very thin coating of boiled linseed oil on the surface of the part.  Not thick or runny, but a nice even thin coat.  The next step is to dust a coating of HARDWOOD ash over the entire surface.  I keep a coffee can of ash from my fireplace in the shop for this purpose.  You want to make sure that the ash is very, very fine, about like talcum powder.  Anyway, dust the ash on.  Hang the part on a piece of coathanger or heavy wire.  Use a propane torch to slowly heat the part.  You will be able to see the part change color from straw to purple to light blue to full blue.  After it reaches full blue, it will get light again and then go through the colors again.  When it reaches full blue the second time, remove the heat and let the part cool.  Do NOT let the part get red.  Dust off the part and apply some oil.  Let it sit over night to let the blue harden.  Blueing is an oxide and is a little fragile when it is new.  If you have an old copy of Machinery"s Handbook, the process is similarly described there.  It also lists the various colors associated with different tempuratures.  You want to keep the temp below the critical  temperature where the steel is compromised.  Anything below the red color is ok.  Springfield armory used ovens to control the heat, but I didn't have one that went to the right temperature.  Try the process on some scrap steel first to get the hang of it.  Remember, the higher the polish, the better the blue.  As I also said earlier, this is difficult to do on a barrel, because the frame acts as a heat sink and you will not get an even blue.  This finish is very durable as is witnessed by the finish on any of the old trapdoor Springfields.  Good luck.