How to case harden a part.....

[RightWinger]

I am very happy I was able to bob the hammer myself and polish it, but the hammer was on a 686-4 and I liked the original case hardened look, and have read on the internet different ways to case harden parts with a torch, a steel box of crushed charcoal and room temperature water....has anyone tried this method or does anyone have a better way? I have heard some people just put bluing on it and it looks close to case hardened, but I would prefer to actually case harden the hammer back to its original hardness and color. any help would be appreciated!

 

[Spotteddog]

You'd need to know what method was used initially, in order to duplicate it exactly? FWIW, the area the spur is being mowed off from is in a non-stress, low impact location. The real question would be, whether the appearance could be duplicated precisely even though fresh "raw" previously un-treated material was being newly exposed and heat treated? I'm no expert in that area, but I'd tend to doubt it?

 

[Milton]

I have used Kasenit to case harden eye talian revolver parts but could get little to no color.The best thing to do is find a professional who does this and let them finish it.It will not be cheap but you will be happier in the long run!

 

[Pisgah]

As the spot where the spur was is not a wear area, casehardening is not necessary, in a practical sense. If you hit that spot with a bit of cold blue solution, you may be surprised how well it blends in to the rest of the hammer finish. Color casehardening is not something an amateur with a propane torch and a bag of Kingsford charcoal can accomplish.

 

[Scrapper]

I have case hardened parts before. I remember in order to get the swirly blue and green finish on a workpiece I would fill a 5 gallon bucket 2/3's the way full with water, then would put enough motor oil in to cover the surface of the water, the oil would of course float then after you heat your work piece to temp. dip in case hardening compound, heat again, then quench, when quenching slowly and steadily dip the part in below the surface of the oily water and hold, obviously do this outdoors, your working with flammables and noxious fumes here (poisonous fumes if you will).

I'm sure there are other variations to this but it's what I've done many times over with success.

Important Reminder: I used this process for parts that do not take considerable loads (High Pressure, etc.) as I rarely had access to a hardness tester so I used the old technique of testing (used a file to see if the surface hardened to the level I wanted). Generally for Machine tools (for Aesthetics). Keep in mind that knowledge of metallurgy is important to the strength and reliability of any homemade or altered parts.

 

[RightWinger]

I really appreciate everyone's advice, and I figured I would hear several people tell me that the area where the spur use to be is not a high impact area and it does not need to be heat treated, this I know however I just think it would look better if the bobbed portion of the hammer matched the trigger......and if it was possible to do in my own home I always enjoy learning a new process. Here is a question, does anyone have any idea what type of SS S&W used on their forged hammers? The reason I ask is that I would like to try some various methods on some practice scraps of SS I have out in my welding shop. It would be interesting to see what methods worked the best and I could post some pictures of my various results.

 

[dfariswheel]

S&W only used actual stainless steel hammers and triggers on the very early Model 60 and 66 revolvers.
They were not satisfied with how the parts wore, so they quickly discontinued the stainless parts.

What they did was install standard color case hardened hammers and triggers on which they applied a coat of hard chrome. This was to prevent rust and make the parts more closely match the stainless of the rest of the gun.

In the 1990's, S&W stopped putting the hard chrome on as a cost savings and the later forged models were the standard color case hardened parts as used on the blued guns.

So, most "stainless" S&W hammers and triggers are actually hard chrome plated.
S&W still believes that stainless steel is unsuitable for their design revolvers.

 

[Scrapper]

Hey very interesting dfariswheel thanks for that info....I really didn't know the history on that.