doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Annealing Problem - Help and Advice requested!

Hi, folks,

It appears that my kiln, irritatingly, dropped its power I saw this when it had gone from 820 to 750 degrees mid way through the "hold" process of 1 hour of the annealing time.

I've now ended up with a hard crust (Which I assume is the old hardened metal" on the outside of each of the parts I have annealed.

It's probably an irrecoverable disaster but I wanted to check to see if anyone might advise on how I can remove this. I've taken a photo of one of the side plates that I have cleaned up next to one yet to be cleaned and you can see the mess the other one is in. I can of course clean the hammers and the side plates in the same way. My problem is the action.



Now clearly I'll have to get the gun re-faced which is irritating (I think I will anyway) because the surface I remove on the action face will be enough to create a gap. But how the heck am I going to get this layer off the inner parts of the action? Does anyone know of a chemical that might just take off the crusty metal??

Any help much appreciated!!

PS I followed Oscar Gaddy's piece from the journal a few years ago.

Regards,
Tony

Nitric acid will clean it like a new piece of metal in minutes. Be very careful with nitric acid and read all the warnings and heed them to the letter. You may also try some Naval Jelly rust remover.

What I think I see may be the result of air intrusion into your crucible. You did use a crucible packed with charcoal dust, correct? Or a vacuum furnace would be even better.

I have no idea but i certainly hope it comes out ok.

Didn't you say in an earlier post that you used aluminum foil to exclude the air? And that the foil had melted and disintegrated? If that's the case I fear you may have done irreversable harm to those parts.

The old toolmaker method of foiling in a heat treat oven employs stainless steel foil, tightly sealed over the part which is wrapped in newspaper. The foil must be sealed air tight. I've seen my friend literally TIG weld the foil shut to ensure this. The newspaper burns and consumes the oxygen. This is a time tested method.

Hi Hammer, yes I did and I didn't it appears use a completely air tight box either. I can get any of the foil off with some elbow grease so I don't think that has done too much damage.

I can't get nitric acid here as an individual and frankly I don't fancy playing with that stuff. I could try the rust remover but I'm not sure that will work will it? it's more like a hard but removable serface. If I gently tap the surface it comes off like a crust.

T

Muriatic acid (HCL) is much safer and easier to get at any hardware store. Mix it 50/50 with water and immerse the degreased parts until clean. After cleaning, rinse the parts well with baking soda/ water solution to neutralize acid. Apply WD-40 or some other water displacer immediately as the metal is chemically clean and will rust in a heartbeat.

OB

Guys, something like this worth a try?

Thing is it's quite a hard shell not really rust or will it still work??

http://www.halfords.com/webapp/wcs/store...yId_165594#tab3

If you are successful in salvaging your parts, perhaps it is time to practice on an old action, or various junk parts before you try to case harden that lovely old Greener. I've never been keen on re-casing old guns. I know it can be done without damage by expert craftsmen, but those fellows have had years to perfect the process. Some things are best left to the experts. Good luck and keep us informed.

Hammergun, lesson learned I say but I think I can recover it.

OB, this seem right stuff?

http://www.mistralni.co.uk/details.php?id=70