Color case hardening

P

Pipefighter

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Can anyone tell me how to get the color in steel. We are playing around in the shop trying to color some pipe for a bosses project. We have a torch and oil from the threading machine. I heated it and dipped it but didn't get what I am looking for. Can someone give me some advice on how to get the color. Thanks.
 
CCH are oxide colors. A nice job is an art developed by years of trying ! Check gunsmithing books , maybe You tube .bring lots of patience.
Most of it is done by pack carburizing with some organic material included ,bone ,leather for example
 
Coloring of steel can be done with a torch or with some mild acids, but there will be no actual hardening. The method described by Mete works, but requires some skill. Most industrial color case hardening today is done by using a hot cyanide salt bath, definitely not something recommended for a home or small shop environment.

Jim
 
It is quite complicated. First you have to know what kind of steel you are using. You need a furnace that you can have some control over holding a set temperature. You need some type of recepticle that you can seal the steel in while in the furnace. As mentioned already, you need something with carbon to pack the steel in. This part alone is a lot of work if you go the old way. You need a large container to hold water to quench the steel in. It is not necessary, but I used to induce oxygen into the quench water. So a compressor would be nice.
If you only want to case harden without the color using a torch, buy some Kasenite. MSC and other supply houses carry it.
 
I guess I thought it wouldn't be to complicated. All I was looking for is color. I heated to a dull red then dipped it in some threading machine oil. As it cooled some color came in it. A pink salmon and a little blue. I noticed there were places where I waved the torch and held it too long and it left white lines in it. It also made any grinding marks stand out. Also I was using A53 pipe.
 
To color using a torch, just polish the steel. Then with the torch set to a blue flame about an inch long, hold it to the item in spots or brush it slowly on the metal. That will color the steel, but with no actual hardening. Practice on some scrap steel and see how it comes out.

Jim
 
Yes, bone and leather work, but you have to burn and crush down a lot of it to pack. Some bone fertilizer will work. If you don't care about hardness, you could try rolling the steel around in that stuff with a torch. I don't know, I never tried to color with out hardening. I tried adding all kinds of stuff and some did seem to change the color patterns. The really popular method the last few years is bone and charcoal, but from what I have seen, it does not bring out the bright yellow and gold colors very much. As mentioned earlier, cyanide is probably the best for color variation, but extremely dangerous to work with.
 
Was it Brad Angier wrote a book on coloring etc,of metals?
Clyde Baker's book covered it,too.(Theseare OLD books,may be hard to find)
Oh,one more thing.

If you DO decide to try pack hardening with bone,charcoal,leather scraps,and maybe some salt or lime,for the colors....
You put it in a sealed box,and heat it up to carburizing temp,etc.

What you don't want to do is seal it all up in a vessel,like a pipe with two caps,where it will hold pressure.

Think about moisture,steam,and the pipe blowing up.
 
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"...Traditional recipe included: Ground bone. Burnt leather..." Yep and literally baking the steel in that.
Doubt you'll get anything pretty with the steel in a pipe using heat. I'd find something to distract the Boss until he forgets the idea. snicker.
However, cold bluing will colour pipe steel though. And there are lots of formulas in Machinery's Handbook for colouring metals. All of which involve nasty acids and chemicals.
 
I did not say "Stick it in a pipe and screw a cap on it". You have to be able to dump the whole mess into water. A clay seal around your "Lid" is fine.
 
Gunplummer,did not mean to imply you did.
I just recalled a horrible accident back in the 60's in high school.Shop kidswanted to bend some pipe.Filled it with sand and capped it,then put it in the forge.It blew,put steel in the kids head.Sand was not dry.
 
Pass

I would think the cheapest and most sure fire way to get good results would be to carefully wrap it up but it in a good box and send it to a professional who is experienced and has a shop set up to do that kind of work. From all I have read its not a home do it yourself type job
bb
 
This is how the project turned out. You can on the end of the feet where I ground the capped ends. That was what I wanted to color. This goes in a man cave gun room. Don't blame me for the design.
 
Color case hardening

I have a box of tempt sticks, that would be close to 46 tubes of what look like crayons. Does the OP want case hardening or color case hardening?

F. Guffey
 
True bone and wood charcoal color case hardening is not all that difficult if you have the right equipment. I routinely do it and have for years used it as a class project in one of my introductory manufacturing processes courses at UND. Though there are a lot of variables that come into play, this is our basic procedure.

Parts are polished to at least 320 grit by hand and than cleaned using denatured alcohol and allowed to dry. Meanwhile a 50/50 mix of wood and bone charcoal are combined. We use the charcoal purchased from Brownells, though there are other sources. We often wrap our parts with degreased black iron wire which can help with the patterns achieved.

My parts are packed in an inverted pipe crucible that sits on a steel carrier. I take care to make sure none of the parts are contacting the sides of the crucible and that the charcoal mixture is well packed. The parts are placed in the furnace and held at a temperature of about 1450F for at least two hours. Following this they are taken out of the furnace and dropped directly in the quench tank. Any air exposure will ruin the colors. This is an example of a project I did some time ago for a customer who wanted a really heavy throwing knife for hunting hogs. The casehardening actually isn't a bad heat treatment for such a knife.

RandallandJohnsonBowie1.jpg


One thing that people need to now is that if any of this is being used for a firearm you better have a good understanding of what you are doing. Improperly done you might end up with some really nice colors and a really dangerous, or wrecked firearms.
 
What type of steel is that? That is really yellow for charcoal and wood. I used to induce air into the quench barrel. Stick an air hose in the bottom of the barrel with a bunch of holes drilled in a plug. I put it below the catch basket. This will help to give you more of a splotchy effect. I agree. Since Brownell's introduced their color case system, there are way to many people doing receivers that should not be.
 
The yellow is more from the photo than the actual part. Though it does have a good display of colors. The steel is just 1018 mild, though I have worked with other alloys. I don't go out of my way to add air to the water, but do add some water right before I quench which helps to oxygenate it a bit. I prefer the process of wrapping the parts in iron wire before packing because this greatly enhances the pattern and is much more consistent than airlines in the tank in my experience. I suspect some of the older color case hardening formulas actually added cyanide to the charcoal pack and this no doubt brought out some of the red colors.
 
I tried adding seeds from apples, apricots, peaches, almonds, and all kinds of stuff that supposedly had cyanide in it. Did not seem to do much. I talked to one guy that was going to add some type of rat posien. I don't know if he ever did or not.
 
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