Annealing/normalizing case hardened steel.

[Dulltool]

Hey guys,
I have a old Remington rolling block No.4 (.22 LR) that has a case hardened frame. Can I normalize it by using a propane torch?..... if so what color should I be looking for? I am not worried about scaling on this particular part.

Right now it's like trying to engrave glass with a wooden popsicle stick.
Any and all comments will be very much appreciated.

THANKS,

 

[Tim Wells]

I believe I'd use a kiln to heat it evenly rather than a torch which you can't use to get the whole thing at the same temp at the same time. You don't want it warping and that uneven heating will cause it. Generally, heating steel to red and letting it air cool with no quench will anneal it but that depends on the particular alloy too so your mileage may vary.

Different alloys require different and specific annealing/heat treating procedures, target temperatures and timed cool down so I'd do all the research I could before going forward. I'd ask Turnbull or the like to get some info. Even when done properly, it can still warp just for spite...

 

[Barry Lee Hands]

To answer your questions, the torch will not bring the whole action up to the needed temp for annealing without a container, or box, essentially making a furnace, to retain the heat, which could be done, but is probably a lot of trouble to make, if you dont understand the concept to begin with.
What you are doing with annealing is actually tempering. The piece was hardened when it was colored, and now needs to be drawn back, in other words, tempered, or annealed.
A hardened piece of carbon stelel when brought to straw color, is drawn to about File temper, when heated to blue draws to spring temper, and when heated past that to grey becomes softer again.
After heating to grey however, it needs to cool slow and even to stay soft and minimize warpage.
If I were you, and had access to a self cleaning oven, I would set the action in a bred loaf pan, cover it with clean sand, set it in the oven and put the oven on a 4 hour clean cycle, and leave the part in the oven till the next day.
This will draw it back to spring temper or so, and that should be a great improvement over the present situation.

 

[fegarex]

Barry beat me to this but I never thought about using sand. I will use that the next time! I've wrapped non-critical parts in foil and did the oven clean thing and it usually makes a nasty part tolerable.
I guess if this was my personal rolling block I wouldn't worry about getting it case hardened again but if it was a customer's I would make sure to cover your rear and get it hardened again.

 

[Dulltool]

Thanks for all the input guys...

I am now looking into picking up a small electric kiln (900 degrees) to add to my collection of stuff. I checked with my wife and our oven is not a self cleaner. I also like the sand idea.
I've paid a gunsmith in the past 100 bucks a pop for doing SAA frames.... the kiln will pay for it's self very fast.

Thanks again for all the help,

 

[JJ Roberts]

annealing

Im glad Dennis ask this question I have a Remington Rolling Block pistol made by Naval Arms,but the color is done with cyanide.After I crank off the barrel what do I do the get the cyanide finish off?:heat up: J.J.

 

[Mike Bissell]

I've used the method that Barry Lee Hands described and it does work.

Mike

 

[DakotaDocMartin]

Thanks for all the input guys...

I am now looking into picking up a small electric kiln (900 degrees) to add to my collection of stuff.

I wonder if 900 degrees is enough? From what I've been told, a Ruger loading gate (for example) needs 1500F for about 90 minutes to anneal it. I know my Neycraft Fiber Furnace kiln has a range of 300F to 2000F. I wonder if 900F max would limit you too much?

I was shocked to see that Brownell's now sells them for $1,079.99! When I bought mine it was about $375.00 But, I guess it was a bunch of years ago too.

Update: Duh!... I just noticed you are located in a country that probably is using the Celsius scale. So, 900 ºC = 1652 ºF. That should do it OK.

 

[Dulltool]

JJ..... I use phosphoric acid for the hardware store (Home Depot)... It's in the paint department. I use it to French grey, removing bluing and chemical case coloring removal.

Doc..... Although it sometimes feels like another country... but Orcas Island is located on the Canadian border in Washington state......We are Americans here!

 

[DakotaDocMartin]

We are Americans here!

Must be all the meds I'm on for the new hip I just had installed. I can't say it's made me the sharpest knife in the drawer.

 

[JJ Roberts]

Cyanide

Dennis,Thanks for that information about removing the cyanide color from the pistol frame.J.J. :thumbs up: