Welding Tips and Tricks

Hey guys, wonder if anyone could tell me about welding small case hardened parts, which can be then re-case hardened, including the weld/build-up?

I have a number of Winchester rifles that I am looking to restore. They all have one thing in common which needs attention. If I say its a sort of case holder, which has a moving part (case extractor hook) which rubs in a groove. Ummm, well the description isn't that important I guess.
Anyways, the groove has become worn by the action of the “hardened” case extractor hook’s sharp edges.

Okay, I need to build up the groove with metal, then machine it back to tolerance (by milling), then I need to re-case harden the part, specifically the metal that I have added to the groove.

Although I have a fairly decent welding setup, I am new to TIG, and MIG pretty much. I would be grateful of any help in pointing me in the right direction.

Thanks.

Generally I believe that after welding the parts need to be annealed and then hardened.

Do you know what the material is, if not how will you select the filler?

LtBadd wrote:Do you know what the material is, if not how will you select the filler?

It is apparently a low carbon "gun" steel. Vague I know but thats about all I have. The parts were rough forged prior to machining then cyanide solution case hardening.

You need small diameter wire, ER70 works fine. And I mean small diameter, like 0.045 or smaller. Controlling the fill is your greatest trick. As said, after welding build up, anneal it before hardening. This is a job for TIG not MIG.

cj737 wrote:You need small diameter wire, ER70 works fine. And I mean small diameter, like 0.045 or smaller. Controlling the fill is your greatest trick. As said, after welding build up, anneal it before hardening. This is a job for TIG not MIG.

Thanks Weldmonger. I'll give that a try.