# Color Casehardening: A photo and video tutorial



## 44-henry

I dont know if this process has been covered here before, but here is a description of how I do it. Many of us have heard of casehardening, the process of adding carbon to the surface of low carbon steels providing a hard exterior shell around a soft inner core. This is a process that has been practiced for hundreds of years and still continues to be a valuable process for many present day manufacturing companies. Though casehardening can be accomplished in a number of ways, Kasenit is perhaps the most common and does provide, at least, a thin hardened shell on small parts. It does not, however, provide any colors and the surface is instead a dead gray color. Below are some examples of the colors produced by the bone and wood charcoal pack process described here.







[imghttp://img.photobucket.com/albums/v733/44-henry/ColorCasedCylinders.jpg]http://[/img]

















Color casehardening is not all that difficult to do; however, it does require a source of high heat such as a kiln, forge, or oven and an accurate way of measuring the temperature. It is possible to get colors when using casehardening compounds containing potassium cyanide and supposedly they can be used much like Kasenite; however, the dangers associated with working with this form of cyanide has prevented me from experimenting with it and also the colors produced in this process are inferior, in my opinion, to the colors obtained by the much safer pack hardening process using wood and bone charcoals. For this reason, this is the process that I will describe.

Currently I use an electric heat treat oven that was purchased from www.brownells.com which has two elements and a chamber capacity of about two square feet. The electric furnaces are more easy to control; however, they do have the disadvantage of reduced element life and using charcoals that are not chemically clean will definitely shorten the life of the elements. Some have had very good luck with gas kilns and this is something I would like to experiment with in the future. I have also used a smaller Neycraft oven that was also purchased from Brownells that works well for smaller articles and it is much less expensive. Here is a picture of the smaller furnace.






One of the secrets of good color case hardening is the type of charcoal used. Throughout history no doubt many different compounds were tried in a quest to improve the process and perhaps obtain better colors. Most early formulas mentioned in gunsmithing texts do suggest that the use of bone, wood, and leather charcoal was common. Others also mention the use of more exotic elements such as salt, fruit pits (charred), and potassium cyanide. Though I have experimented with the leather charcoal and salt, the other items (especially the cyanide) I have not tried. I suspect the fruit pits might have some promise as some pits contain trace amounts of cyanide. 

The charcoal that I have had the most success with has been obtained from www.brownells.com and is wood and bone charcoal. These two charcoal types have proved successful in creating colors that match the original colors that one sees on fine old guns such as Colt, Winchester, LC Smith, Parker, Remington, and many others. Below are some examples of the colors that can be obtained.

To be successful in this process you must understand some peculiarities about this process. Normal casehardening involves nothing more than immersing a low carbon steel object inside a carbon rich atmosphere and than heating to above critical temperature. The longer the object remains in the pack surrounded by the carbon the deeper the resulting case will be. Temperature also plays a role in this as the absorption of carbon is quickened by the higher temperature ranges. The parts can simply be taken out of the pack and quenched and the casehardening will be successful as long as the part is quenched before it cools to below critical temperature. 

Color casehardening requires more care. In color casehardening the parts need to be immersed in the carbon material in a sealed container and the temperature is critical for if it is too high the colors will be poor and washed out. Few people know it, but it is actually possible to get very good colors under the critical range; however, if this is done you are not really casehardening, just coloring. I have found that temperatures should be close to the 1400 degree F mark. When the temperature climbs much over 1450 the colors seem to be rather poor. Just as important is the process used to quench the parts. If air contaminates the parts before they hit the quench the colors will be spoiled. For this reason it is very important to make sure that a method is devised to allow the parts to be moved directly from the crucible to the quench as quickly as possible. For this reason I have devised the following crucible seen in the photograph below.






This crucible makes use of a length of 3 diameter steel pipe (stainless would be much better) with a cap welded on one end. The other end remains open. A pipe nipple is welded to the middle to allow gripping with a pair of tongs. The crucible is loaded with the polished, degreased parts, and packed with the chosen ratio of wood to bone charcoal. We have used different ratios, but most of the time I have settled on a 1:1 mix of wood to bone. It is important to keep the parts from touching the sides of the crucible by about ½. Add the charcoal in layers, tapping the crucible at regular intervals to settle the charcoal but do not tamp as this can pack the parts into the crucible so tightly that they can hang-up during the quench process. Make sure the charcoal is all the way to the top and then level of with a flat bar or stick. Next the crucible is inverted on a stainless steel carrier and any extra charcoal packed around the sides of the crucible. You can see this clearly in the above photograph. 

The crucible is than placed inside the furnace 
	

	
	
		
		

		
		
	


	




 and the temperature is allowed to climb until the crucibles internal temperature reaches 1400 degrees Fahrenheit. Since the internal temperature is difficult to measure I just allow 30 minutes to 1 hour to compensate if the furnace is already pre-heated. If you start from a cold furnace I generally dont worry about it and just start the clock when the pyrometer reads 1400 F. Once the temperature is reached allow about 2 hours of cooking time.

Meanwhile you should prepare the quench. I generally just use plane water that is as cold as I can easily get it. I shoot for a water temperature of 35-40 degrees F. I generally accomplish this by putting a block of ice into the water a couple hours before I start the oven. At this time I also supply air to the tank via an airline that runs into the bottom of the 32 gallon barrel that I use for quenching. See the photograph below for a picture of an older tank that we used to use. Some texts suggest placing Potassium Nitrate into the water to increase the colors obtained. I have experimented with this and have found that it does indeed provide more blues, but more experimentation is needed in this area. Basically I think there are two main variables that are important here. Water temperature is one and oxygenation of the water is the other. I think that is far more important to run the airline into the water before the quench than it is during. At some point I will obtain an oxygen monitor to measure the oxygen content of the water as I think this could provide some interesting answers.

If you pay attention to the quench tank in the photo and also the video clip you will notice a lid on it. The lid has an opening in the center along with a steel lip welded to the top just before the hole. In use the carrier with the crucible in tow is removed from the furnace and placed on the steel lid. The carrier is than positioned to butt up against the steel lip. At this point the operator changes the position of the tongs to the crucible and slides the crucible over the hole in the tank. Since the water level is right at the top of the lid the drop is almost instantaneous. The following photos demonstrate the sequence of events.


























Lastly here is the video clip that I took of one of my students doing this process on one of the baseplates for their steam engines.

http://smg.photobucket.com/albums/v733/44-henry/?action=view&current=ColorCaseVideo.mp4

 I think the drop distance does have some impact in the colors obtained, at least according to Dr. Oscar Gaddy who did an excellent article on the process in the Double Gun Journal some years back. In the future this is an area that I will explore further. 

My observations on the process to date suggest the following:

The parts need to be clean and well polished. We clean are parts with rubbing alcohol or TSP solution that the parts are boiled in for 30 minutes (followed by boiling for 10 minutes in clean water). The parts also need to be polished to at least 320 grit. The better the polish the more brilliant the colors will be. The polishing should be done with sandpaper with a proper backing to preserve flat surfaces and prevent rounded corners and dished out holes. Buffing does not yield good results and even seems to reduce the effectiveness of the process for some reason. In any event I dont feel buffing has much of a place in fine polishing as it tends to round corners and dish out screw holes.

The longer the charcoal mixture can be kept in contact with the parts to be hardened the better the colors will be. Shields, blocking, wire wraps, etc. all seem to improve the dramatic display of colors. Note: my students often wrap the parts that they harden with several layers of thin iron wire which should also be degreased. The wire makes a huge difference in the colors that can be obtained.

Parts will warp if left unsupported. If you try casehardening a thin strip of metal you can expect it to bend if it is not supported with some form of blocking. 

The colors will be improved by a post tempering operation in the oven at temperatures up to 450 degrees F. This also reduces the risk of excessive brittleness if you happen to have casehardened a high carbon piece of steel or have thin sections in your low carbon parts that might have been penetrated by carbon all the way through. Skip this step if you do not want to reduce the hardness of the surface. 

Wash the parts after the quench in hot water to remove residue and then oil or lacquer to protect the colors. Note: the colors can wear off easily so some form of protection is desirable. Many feel that the colors are also UV sensitive; however, I have never seen any definitive evidence to support this.

If you have any additional questions please dont hesitate to ask. I am far from an expert in this field, but I continue to learn each time I, or my students, participate in this process. Please share your knowledge if you choose to experiment with the process as that is the only way to keep this dying art alive.

Regards,
Alex Johnson


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## 90LX_Notch

Alex,

Thank you for posting this. I've always liked this look on Starrett tools. This is something that I would like to try sometime in the future.

Bob


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## RobWilson

Thanks Alex , for sharing ,very informative post ,think i may dig out my small electric furnace and give it ago
Rob


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## PhillyVa

Alex,

I often wondered how that was done (the case hardening that is). I never looked into it in detail...Thanks for sharing, that was very interesting....you deserve a :bow: point :bow: for that. woohoo1

Regards

Philly


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## GrahamC

Alex,

Thanks for posting that, very informative.

I really don't have the space to set up to do something like this. Any casehardening or hardening in general I do is on a smaller and simpler scale.

I had read someplace (forget where) that you could caseharden by quenching in house hold ammonia. Tried it, didn't work but I did get a very nice "blue" colour over most of the part. I have repeated my experiment and it seems to be somewhat repeatable although I have never pursued it. One variation I have thought of trying is to use Casenit to caseharden but to quench in household ammonia rather than water. Like pottasium nitrate, ammonia is rich in nitrogen which is helping to impart the blue color. Ammonia is a pretty strong alkyly (spelling?) and rather odiferous (strong smell) - so for anyone conisdering trying this, use only outdoors with plenty of freshair and do where appropriate face and body protection.

cheers, Graham in Ottawa Canada


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## 44-henry

I have no idea about the ammonia, but it sounds interesting---and very smelly. There are some chemicals that can be used to provide artificial colors that can be useful in creating a faux finish (or touchup to an existing color case job).


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## JackKnife

Thank you very much for all the info ! I am a knife maker and i dable a bit with some gunsmithing ! I intend trying some casehardening in the near future ! I want to see what it does for spring steel ( 5160 high carbon steel ) and also a rifle action in a low carbon steel ! 


I do have one question though < can the quench be done in a high quality quenching oil ? Has anyone tried it and if so what were the results ? 
I intend playing a bit and will post pics if the results are good ! 8)


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## michal1138

Alex, Good article, I have one question?.....Can I color case harden a shotgun barrel with shell chamber without it warping< I have an older SW eastfield riot gun 12 guage 18" barrel and it is pretty worn, and I would like to pretty it up so to say and add some strength to the chamber. I would be most gratefull to know as I don't want to ruin the barrel. I inherited it from my brother who was a Sheriffs deputy and died in an auto accident.
Thanks for the article and your time, if I don't see a post my mail is [email protected]
Michal


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## 44-henry

Michal, 
You definitely do not want to do that. Warping would be the least of your problems as you could very easily make the barrel brittle especially in the vicinity of the chamber. I have never seen a modern firearm with a color casehardened barrel and for very good reason. If the gun were mine I would double check to make sure the barrel is, in fact, legal length (18" is bare minimum) and than assuming everything was OK clean and oil the gun and keep it as a memento. Most of my gun work is with muzzle loaders and if you want to get into this type of work these are good places to start.


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## TravisT

I love the look of the color casehardened parts. Is that color and finish permanent or could it rub off over time? Does it depend on the thickness of the casehardening?


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## maverick

The colors or colored layer is very thin and is susceptable to wear, usually by moving the parts like hammers 
 and levers on rifles or holster wear on revolvers. Prolonged direct sunlight can also fade the color.
 A thin coat of lacquer or equivalent is sometime applied to protect or enhance the color.

Mike


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## 44-henry

The colors will wear off, but are not as fragile as some would think. There is considerable debate about whether they are susceptible to sunlight and I do not know of any definitive proof of this. You can use a coating like lacquer to protect the colors, but I prefer to just protect the finish with a light coat of oil.


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## BigHat

This is very interesting and thanks to those that shared info. 

I have a question though. Turnbull is doing a CCH frame treatment on a 1911 pistol for me. I understand Turnbull does spray a coat of lacquer on its CCH surfaces. I'm just wondering if the pistol frame is weakened by the process. I understand CCH used to surface harden low carbon steel of years past, but what impact does it have on a modern carbon steel gun frame?

Thanks


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## 44-henry

I do not know what kind of steel would be used on your particular 1911. It is possible to color case harden high carbon steel parts and I have done this in the past in a few special circumstances, but I try to avoid it if possible. Turnbull makes this his business and I have no doubt if he is doing it it will be done correctly and I would only be guessing at the approach he will be taking. 

A couple things that I have found is that you can temper casehardened parts just the same as you do with high carbon tool steel. As long as you keep your tempering to under 450 degrees F you won't impact the colors negatively, in fact I often do this anyways as the colors are actually enhanced by this tempering process. It is also possible to get very nice colors under critical temperature. In these instances the parts won't be hardened to any significant degree. Some people actually advocate this as they feel that there is less danger of warpage at these lower temperaturs and they are probably correct, but I the process is no longer color case hardening at this point, it is just case coloring. Nothing wrong with this if you don't need hard surfaces, but I am skeptical of its use in firearms parts where the color is generally secondary to the importance of having a good hard wearing surface.

Hopefully that helps answer a few questions.


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## BigHat

Thanks Henry. Very good info.


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## kvom

video clip asks for a password ???


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## 44-henry

Sorry, it does look like that link is not working. I believe that I fixed the problem, but here it is again just in case:

http://smg.photobucket.com/albums/v733/44-henry/?action=view&current=ColorCaseVideo.mp4

If it prompts you for a password enter: casehardening


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## 500_A-Square_Mag

Henry,
Thank's for the great article and video. I have a question regarding CCH on the receiver of an older Ruger No.1. The Receiver is made of through hardened 4140 or 4340. I have been told that it may not be a good idea to CCH this material. I am really looking for the color, not the case hardness. is it possible to do this process at the lower temperature you talked about in the artcle? if so what is the lowest temperature that you have seen good color? 
Thanks,
Brad


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## dwade7551

This is great information. I have a chance to buy one of the smaller Neycraft furnaces for a very good price. The inner chamber is 9"x9"x6.5". What did you find the limitations to be in practical terms? Also, what have you found to be the lowest temp that you can produce colors at? I'm more interested in producing colors in alloy steels rather than hardening and am very concerned about warpage.


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## NitroExpress

Hello Henry,
Do you find that the use of Barbeque charcoal in case hardening is acceptable, or is this a modern synthetic substitute for willow charcoal, also what size "lumps" do you break the charcoal into? I am sure the size must make a difference to the colours obtained, I am about to use a 50/50 Wood, Bone charcoal mix, held close by wire wraps. I have tried to contact you via your old University E-mail address to no avail.
Regards,
Chris Buckingham.
France.


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## 44-henry

NitroExpress said:


> Hello Henry,
> Do you find that the use of Barbeque charcoal in case hardening is acceptable, or is this a modern synthetic substitute for willow charcoal, also what size "lumps" do you break the charcoal into? I am sure the size must make a difference to the colours obtained, I am about to use a 50/50 Wood, Bone charcoal mix, held close by wire wraps. I have tried to contact you via your old University E-mail address to no avail.
> Regards,
> Chris Buckingham.
> France.


 
Sorry, I haven't been around for awhile, so forgive the late response. I have recently updated my profile with current info; however, I am still at the University. I have not personally attempted the use of briquettes, but I highly doubt they would work well due to the use of binders. My best results have come with the use of chemically pure charcoal. Brownells sells it, and so do some other companies. I have made charcoal in the past from wood, leather, fruit pits, and some other stuff I won't even mention, it works, but it is much less trouble to just buy the stuff from one of the above sources. It really isn't that expensive for the quantity that you will use. We use a fair amount at the lab, but for normal usage a couple buckets worth will last you a long time. I have even reclaimed it from the bottom of the tanks and, once dried, it works just fine and gives great colors. 

The size is important, Brownells lists the bone as 10x28 sieve size and the wood charcoal is #6 mesh. The wire wrap is a good idea, and your 50/50 mix is a good place to start.


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## 44-henry

dwade7551 said:


> This is great information. I have a chance to buy one of the smaller Neycraft furnaces for a very good price. The inner chamber is 9"x9"x6.5". What did you find the limitations to be in practical terms? Also, what have you found to be the lowest temp that you can produce colors at? I'm more interested in producing colors in alloy steels rather than hardening and am very concerned about warpage.


 

I have got some really impressive colors in the 1200 degree F range, but at that temp I wouldn't exactly call it color case hardening. The Neycraft is a good furnace. The chamber is a bit on the small side, but if you can fit it in there it will do just fine. The downside is that the elements will eventually have to be replaced just due to the dirty nature of the process. My preference is really a gas oven, but these are a bit more difficult to find and can be difficult to regulate precisely. The furnace I currently am using is a Johnson Tripple Treat that has been fitted with Honeywell digital controllers. Great furnace, but it costs more than a lot of SUV's. The equivalent could be built for much less however. 

Warpage is certainly an issue that you need to think about. It is less likely to occur at the lower temperature ranges, but can and does still occur. I generally block anything I am really concerned with and this can take a lot of time. Even so, some refitting is often required after everything is said and done.


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## 44-henry

500_A-Square_Mag said:


> Henry,
> Thank's for the great article and video. I have a question regarding CCH on the receiver of an older Ruger No.1. The Receiver is made of through hardened 4140 or 4340. I have been told that it may not be a good idea to CCH this material. I am really looking for the color, not the case hardness. is it possible to do this process at the lower temperature you talked about in the artcle? if so what is the lowest temperature that you have seen good color?
> Thanks,
> Brad


 

I cannot really speak towards the casehardening of an action like the Ruger #1. All of the work that I have done at the university has been non-gun related for obvious reasons. Anything that I do that is firearms oriented takes place in my well equipped home shop.

As for the #1,  I have seen them done like you speak, and even handled them, but I wouldn't go out on a limb and tell you how to do it. When you get involved with casehardening a receiver that is going to be used with high pressure cartridges, you really need to know exactly what you are getting into, and there are a lot of factors that need to be considered that you have not mentioned above. 

Experts like Doug Turnbull would be my choice for something like you are proposing, and, FYI, the last #1 that I handled that had been casehardened had been done by them.


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## awander

I don't understand how the wrapping with iron wire works-do you wrap a layer of charcoal up against the parts? Or something else?


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## 44-henry

The wire is used first and than the part is packed in charcoal as usual. On small parts I try to make a grid of about 1/4" square with the iron wire, sometimes I just wrap it in one direction. One of the keys to getting good colors is to keep the bone charcoal in close contact with the part for as long as possible and the wire helps to do this. It also likely works to disrupt the water during the quench which helps with the colors. I used to use an air stream in the quench tank much like you see others recommending, but the wire pretty much accomplishes the same thing and is more consistent, at least for me and the students that I have taught.


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## awander

Thanks for the info on the wire. Is the wire wrapped tightly around the part, or loosely?

Another question: Do you not find it necessary to seal the pipe to the stainless carrier during soaking? Does the loose charcoal around the base of the pipe take care of this?


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## 44-henry

I wrap the wire fairly tightly around the parts, sometimes it is used to secure blocking to the parts to help prevent/reduce warpage during the quench. The fit of the crucible to the steel carrier (stainless is nice but not necessary) should be close, but air tight is not required or even desirable. 

During the process the charcoal gasses off to create both carbon monoxide and carbon dioxide which should prevent oxygen from getting in. The charcoal on the outside probably helps burn off oxygen present immediately around the opening, but it really isn't necessary. If you are using an electric furnace I wouldn't do it at all because it will definitely shorten the life of your heating elements. Some knife makers do burn charcoal or other organic materials in their electric furnaces during a heat treatment cycle to reduce oxygen inside the furnace and help reduce scaling on the parts, but they also have problems with the life of heating elements doing this. 

I personally prefer gas furnaces for this and other reasons, but I have successfully done color case hardening with electric furnaces also.

Hope that helps.

Regards,

Alex Johnson


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## awander

Thanks, Alex, I appreciate the effort you take to pass on this knowledge.

I am gearing up to try CCH soon, and your article was one of the best sources of info I have found.


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## gocy

Just finished Tubal Cain's Hardening, Tempering and Heat Treatment.
Very interesting!!!!


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## 44-henry

Thought some of you might be interested in this. This is a large throwing knife made out of 3/8 inch mild steel plate that I color case hardened using the same process that I described at the beginning of this thread. The knife measures about 14 inches long and just one ounce shy of 2 pounds and is going to be used by a gentleman that participates in knife throwing competition at local muzzleloader matches. I was trying for something that was a bit unusual and more traditional in appearance than some of the other ones out there. 

















It is a bit different color case hardening something this size in my home workshop and having it come out of the quench tank with no warpage, but the basic principles are still the same.


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## NitroExpress

Well Henry, I reckon you have got just about the perfect English Sporting Gun colour there, I think the spread of colours is about as good as I have ever seen with none of the modern bright blues. Can you tell us what mix you used to achieve this ?
 I would be a very happy man if I could get colours like this.
 Chris,
 France.


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## 44-henry

Thank you. The mix in this instance was about a 50/50 ratio of wood to bone. Changing the proportions of the mix will have some impact, but how you introduce the contents of the crucible to the quench and how they are prepared makes a huge difference also. 

One thing that I do is to wrap the parts in soft iron wire before I place them in the crucible, the other thing is to make sure that the surfaces are properly prepared. I generally polish to at least 320 grit by hand before starting the case hardening operation, rougher surfaces will produce more muted colors. Knife blades like this and others that I do also have to be properly blocked to help prevent warpage which generally will occur on thin sections without prior planning. 

The following picture was a small letter opener that I just finished this evening and it shows a higher concentration of blue which was achieved in part by a higher concentration of wood in the pack. The photos aren't the best, but it should give you some idea of the colors.


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## NitroExpress

Well 44 Henry,
 That is fantastic! I am not normally a great fan of the intense blues, they look much too modern when used on an early English gun but in this application it looks really nice, I always block any thin section that I intend to quench, but I think a great deal on effort is required in "presenting" the piece to the water at the right angle on thin sections, or they will have tensions set up within which can cause distortion , we have all fund that out the hard way!
 Chris ,
 France.


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## 44-henry

This is an example of a type of crucible that I use. I am not at home at the moment, but put this sketch together so you can see. Introducing the parts to the quench is critical, but sometimes it is nice to be able to displace the water and than have it crash around the parts from the sides uniformally. I do this by creating a three part crucible where the body is free to fall into the quench water and it has the parts attached to a central rod either directly, or with blocking. Sometimes it is useful to place a shield (roof) on top of the rod that covers the parts but this is a bit more involved. This style of crucible must be handled a bit differently in that the parts need to be attached to the rod and the main body of the pipe placed over the assembly. The pipe must be a free (read loose) fit on the base so that it falls freely. Sometimes after a number of cycles the end must be ground down to allow a smooth fit. Once the body is placed inside the base the charcoal mix is placed in through the top, being careful to tap frequently to settle the charcoal in all the crevices. At this point the cap is placed on the body and the three bolts tightened to secure it. Once this is accomplished I generally place the whole assembly in the the standard carrier shown at the beginning of the thread and proceed in exactly the same fashion. I do on occasion place the whole crucible on its side in the furnace and than need to creatively lift it out of the oven without letting the base fall free and tip it onto the quench tank lid. This is a bit difficult and can be dangerous if not done correctly, but sometimes the parts that I am doing do not fit height wise in my home furnace. If you have questions please let me know.


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## NitroExpress

Hello 44 Henry,
 I would imagine that the base cap plunging into the quench will cause some kind of cavitation giving an air/water quench to the part being CCH, a very interesting departure, and one which I will certainly try, I think that the range of colours obtained must be a product of very local temperature variations, just the thing you could get with this turbulent plunge method, very interesting, many thanks for passing this knowledge on !
 Chris,
 France.


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## 44-henry

Hello,
My experience has been that the best colors seem to happen when the water displaces and than comes crashing around the part at all sides, you are correct that the cap does have this effect. I have also found anyway that you can keep the charcoal in contact with the part longer will help the process. I have several students casehardening parts this afternoon and we have actually fastened a mesh steel cage that traps some charcoal next to the workpieces, the whole cage goes into the tank from the crucible and the colors we are getting look very good.

Here is one of my latest projects using the cage technique.






Here is a shot of another side


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## NitroExpress

Hello Alex,
I think you have got a really nice colour balance here with fantastic blues, and really nice red hues, it would be an interesting experiment to try this formular/heat cycle, on an object with different sections, I still find I have problems around the edges of holes, maybe I should lodge a large lump of charcoal in the hole.Realy impressed with this project.
Has your new Paper been published yet?
Regards,
Chris,
France.


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## 44-henry

Hello,
Thank you for the compliments. I submitted my paper recently to the International Journal of Modern Engineering (IJME). It will need to go through the peer review process before any word is given on possible acceptance, but it is an open access journal so it will be available if published.  I hope it is the start of much more research in this area.

Regards,

Alex Johnson


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## KentShootwell

Brand new here and must thank Henry 44 for his fine thread. I have picked up a few ideas reading all this and would like to add a bit. For the fellows that want to do a small item you can with a half a tea spoon of Kasenite or a cup of bone charcoal mixed with quart volume of natural lump charcoal broken to about pea size. Place the polished part in a steel container with a cap over the top and this is placed in a good camp fire for an hour or two. Quench in a 5 gallon bucket of water that has been poured form one bucket to the other a few times just before dumping the part in. Use all the tips posted here and you will get something like this.


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## KentShootwell

Did this action with used charcoal as was mentioned in this thread. Worked fine good color and hardness.


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## NitroExpress

Kent Shootwell,
That is an excellent job! Did you block the thin sections ? You have a very nice colour range on this, and that is somewhat of a lottery as you never know what colours will come out from the steel type and of course the way the quench water flows, what bone/wood charcoal ratio did you use for this?Is this an original Sharps action, or one you have made ? It looks very nice! Congratulations.
Chris,
France.


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## KentShootwell

Thanks Chris, This Sharps shows all the blocking I use. Warpage has been very minor and easily dealt with. The mix is 1 bone to 4 wood charcoal. This one was done with fresh mix. Both are new made actions of 8620 and lock and trigger plates of 1117 steel.


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## NitroExpress

Kent,
That looks very nice, I notice you get the light coloured rings around the holes, that sets the blued screws off nicely, the colour you have achieved on both actions is a really nice balance, so many turn out to be very patchy in colour, but you have a very nice spread of colour, just like an old Sharps, did you use rainwater for quench or was there an additive in the water? Chris.


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## KentShootwell

I use city tap water with nothing but air bubbles from an aquarium aerator. The edges generally are lighter due to the quicker cooling I believe. This is a replica pistol I completely refinished with added fancy wood for the grip. And yes I know I miss labeled it.


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## 44-henry

Your colors came out very nice, I particularly like the first Sharps shown, who did the engraving?

I do feel as the one who started this thread several years ago that has now received close to 70,000 hits, that a word of caution is in order. I have studied this process for several years and done many non-firearms related applications with it at the University of North Dakota, and while I have done firearms related projects with it in my home workshop the process of color case hardening any type of firearm action is something that should only be done by someone who completely understands the process. The least of your worries is that you will destroy an expensive action as warping and cracks can occur, but at the extreme it is possible to create something that is dangerous to operate and there is a huge liability that exists at that point.  With the last posts I have no doubt about the competency of Kent who does very nice work by the way, but over the years I have received a number of requests from people that want to start out CCH'ing firearms of various types that I do not have that same level of confidence in.


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## NitroExpress

44 Henry,
You are spot on here with your words of caution, I did read in your enquiries within this section, of a person wanting to CC harden the barrels of a shotgun!!!! I can only think that would end in one of the major disasters of which you speak. The problem is that outside of Europe there seems to be no restriction on what you can do on a firearm, in UK and most of Europe, any alteration to the pressure bearing components of a firearm require  it to go through re proof, most people tend to accept that and not work on those areas, so there is a very low "blow up" of firearms due to inexperienced tinkerers , but your words of caution are very wise.
Chris, France.


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## KentShootwell

44Henrys warning are valid! I'm a retired machinist with a number of years of experience as a custom gunsmith. Even with the training I restrict my self to double shotguns and black powder fire arms. My samples are to show the results of my color case work not to encourage the untrained to apply this treatment at random. We can share our knowledge but we each should not attemp to work outside of our skill sets. 
Nitro, Hearing how it is in the extreme east makes me happy I'm in the Wild West!


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## NitroExpress

Kent,
As a machinist you well understand the strength of materials, not everyone that I see posting on the Internet seems to be aware of these limits, you are very wise to restrict your hardening work to relatively low pressure calibers, I think that as we enter the 21st Century there are less people that have a first hand knowledge of these old trades, it is essential that we keep the knowledge going, too many old skills have been lost because of "trade secrets" but we also have to be mindful of the fact that there are less than intelligent people out there that will try anything.
The situation here is not as bad as the media portray it, at least in the rural areas, I have not seen a dusky face since I have lived here, (7 years).I think the journalist write these things after a lunchtime session in the bar!


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## KentShootwell

Henry that engraver is Martin Rabeno of Durango Colorado.


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## 44-henry

KentShootwell said:


> Henry that engraver is Martin Rabeno of Durango Colorado.



That is very nice work, I am partial to the Sharps action and own a couple Shiloh's. I would be nice to see the completed rifle.


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## KentShootwell

The finished Sharps after the color was polished off to show the engraving.


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## 44-henry

I have had some people request that the broken Photobucket links be fixed on this old thread, seems like everything is now working. Hope it helps someone.

Regards,

Alex Johnson


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