doublegunshop.com - home Forums General Discussion DIY Gunsmithing @ doublegunshop.com Care and cleaning of case colors

What chemicals and cleaners should be used or avoided when caring for case colors? I make the mistake of using full strength Simple Green if softened the case colors on a gun. I've used brake cleaner to remove heavy gummed up oil/grease with no issues. If I have a tight locked up gun that won't budge I'll soak it in 50/50 ATF and acetone. Will that be a problem for case colors?

I'll be interested in the replies to your question, SB. I have read and reread Oscar Gaddy's treatise on case colors many times and I am always left wondering if, and how, any chemical could change the crystalline/prismatic surface which creates the colors and patterns. Of course, RUBBING with any product could do this because any abrasive action alters the prismatic structure. In the same vein, I have always wondered how direct sunlight could fade case colors, as some claim.

Thanks for asking, maybe I'll learn something from it, too.

SRH

I've read that the colored surface is an oxidation reaction. When I hear oxidation I think rust. So that leads me to believe any form of rust remover would chemically remove the colors. I've read toilet bowl cleaner used to remove case colors to get a French Gray finish on guns requiring the case hardening.

Anything acidic will eventually remove the colors, but not the hardness.

Anything that would remove the lacquer/shellac coating normally placed on the case color to protect it would lead to an immediate change in its appearance and through time to expose it to various things to possibly fade it.

I'm not sure anything was applied to the case-hardened area of (vintage) American made doubles at their manufacture. I've never read or heard anything addressing that. However, it is nothing short of amazing how well the colors hold up in the most protected areas. This is the forearm of my Philadelphia made 20 ga. Fox Sterlingworth. These colors are absolutely 100% original. I have refinished the wood. I don't have a picture of the action for a comparison but suffice it to say that there is less than 10% case color remaining on it. Each time I remove the forend I try to imagine what the action looked like when it left Philly with such vibrant colors on it.

Yes, "amazing how well the colors hold up in the most protected areas". I have a 100 year old German single shot with all its colors just as vivid owing to its original coat of lacquer or whatever that is still in place. I suppose a well tended coat of something like Renaissance Wax could preserve any colors left on our guns that weren't protected that way.

Parker Reproductions have notoriously fading case colors.
I put a very lite coat of True Oil on the C C parts.
Works great to protect.
Bob Jurewicz

After complete disassembly I've sprayed Mohawk Clear Satin spray Lacquer to protect case colors.

I believe that some American double gun makers applied some kind of protecting finish over the colors in their guns.

All did. Not just US-Americans. Zapon lacquer, back then.

Carcano

I've asked this question with no results. Has anyone experienced a blacking of case coloring. I had my Smith Trap Grade 10ga. cased. I set it aside and all was fine for a couple of years then it turned black. The coloring is there but it is very muted by the black color. I feel like all it needs is a good cleaning and that will wash away the black? I have removed the protective lacquer in the belief it was the protective coat, it seems to have helped a little but its dark!!

One point is that what is today still is commonly called "zapon lacquer" and marketed as such, has frequently become an acrylate lacquer or varnish. Both may react differently.

Secondly, original old zapon lacquer is prone to yellowing and crackling under the direct influence of UV light, over the decades.

Thirdly, the "case colours" are actually very thin oxide layers, with a thickness of only a few nanometres. The thickness also determines the color (!). Hence, they are rather sensitive to any kind of mechanical influence or wear. The layer thickness of the zapon lacquer cover over them is probably thousandfold.

I don't believe Parker coated their color case hardened frames & parts with anything.
Neither did AH Fox at least when they used Bone/Wood charcoal process on the earlier guns.
The cyanide colored guns , maybe something was put on them.

AH Fox didn't do the cyanide hardening in house. They had (Fred) Heinzelman (sp?) in Carlstadt, NJ do that work for them.
They are still in biz AFAIK. They were a couple of yrs ago at least and would still take in polished firearms parts for the Cyanide CAse Color work.
They had (still have?) an FFL so sending the frame was no problem. Cost was cheap as I recall.
That's where Turnbull sent his Fox work and any other that needed cyanide coloring back when.
Don't know what they do know.

Most everything got 'coated' with a protective something there. All the SxS's that I remember except the Parkers.
Orange shellac was a fav.

Yes the color layer is incredibly thin on the surface.
Depending on how the re-coloring was done, the colors would sometimes start to wear off the high edges
just during reassembly. Especially if you had to take-apart & reassemble a couple times to get that GD SST to work right.

Just some idle thoughts this AM along w/a cup of coffee

That coincides with my assumptions about protective coatings being used at the factories, Kutter. Thanks.

May I ask, what is YOUR opinion on whether or not direct sunlight can eventually cause case-colors to fade away? After I realized through the excellent articles and electron microscope images of the surfaces, in Dr. Oscar Gaddy's articles, that the colors themselves are a by-product of a prismatic effect due the the "crystalline structure" of the case hardened surface, I came to the conclusion that only sunlight (in the absence of handling, such as in a museum setting) alone couldn't alter the surface structure of the steel which causes the colors. I can easily see, however, how handling can wear away the super thin layer and alter it.

I have a simple way of seeing it and am open to other informed ideas about how sunlight could do this.

I've always had my doubts about this also, and for the reason you gave. I don't think sunlight alone could wear down a crystalline structure.

I really would like to hear Jim's opinions on this. I greatly respect his opinions and experience.

Does anyone know if cyanide case colors have the same crystalline structure as charcoal case colors?

I would suppose (rather than merely hope) that Jörg Schilling's doctoral dissertation (Dr.-Ing.) also had covered and examined exactly this very subject.

Carcano

My personal opinion is that sunlight alone doesn't fade casecolors.
Handling the piece, even the slightest wear will do it. Though some pieces are prone to wear much easier from handling than others.
Just the way the individual guns were done.

I have read some reports about sunlight fading case colors on guns in display racks for long periods and not moved around. One side faded where the sun could reach it, The other side not.
I really don't know,,just my opinion.

Getting the colors to appear is not really that difficult. But there are so many variables in the works when that happens, that any number of them can be slightly changed & Colors will still appear. But then you can get what we called 'soft colors',,those that wore off very easily . Or with changes in the variables, colors that withstand the handling and wear better and don't disappear on you in a season of light use.

Some mfg'rs colors just seem to withstand time and handling better than others. Just the particular way they did theirs I guess.
Maybe the steel alloy is involved as well. Again there are dozens of variables that can be 'adjusted' and still get colors. What else is changed when the adjustments are done could be one involving how permanent they are.

Colors can be had with no surface hardening, that's another variable to the whole thing. These seem to wear easier as well.

Cyanide colors always seemed much more resilient to wear than charcoal process colors.
We never did any cyanide work (in spite of what the NYSDEC thought when they came knocking, but that's another story).
But plenty of guns came in with the cyanide hardening and colors on them to be re-done to wood/bone charcoal colors.

Cyanide hardened/colored parts seemed more difficult to anneal.
The technique used was caveman, maybe that had something to do with it !!
But it worked fine for annealing guns that were orig bone/wood charcoal colored.
Cyanide colored parts sometimes had to go through the 'process' a couple times to be assured of a soft surface before I could do any re-cutting on them.

Thanks so much for that reply, Kutter. You never disappoint.

Best to you, SRH

BTW, some years go I did a thorough search for Fred Heinzelman in NJ. I called the listed number numerous time with never an answer. Next, I called the post office there and inquired about the listed address. I was told by them that the address was vacated, so I gave up.

SRH

We still haven't gotten to the "method" of cleaning tarnish from real case colors on old Parkers. Three pages and no help.

Ultrasound.

Never heard of him or his dissertation. Who is he? Any further information?

His dissertation is from 2003. Unfortunately for me, it was written in German. If that is what you referred to, it appears to be about microscopy techniques, not chemical structure, per se.

On my Perazzis I disassemble, thoroughly clean with acetone, and spray a couple heavy coats of Rustoleum clear poly. That will get it as clean as it's going to get with zero damage, and protect it better than any lacquer on the planet. I do it every 2-3 years on the ones used all the time. Colors have not degraded beyond what might have transpired before I got them.
The oldest is an early 70's gun and I've had it 30years or so. Colors were not too good then but are no worse now and it was out with me every week for nearly 25years.