Case hardening help

[RAT]

I'm about to try my first attempt at color case hardening. I'm building an 1860's period Gemmer style Hawken rifle. I'm a little worried about some parts warping. Can anyone offer advice on the long trigger plate, trigger guard, and tang? Do I need to construct bracing for these parts? I had thought about packing the trigger plate and trigger guard assembled as a unit, but I'm pretty sure that's not the way to go. I'm about 2-3 weeks away from this attempt. I may try to post some photos.

[Bob Roller]

I'm about to try my first attempt at color case hardening. I'm building an 1860's period Gemmer style Hawken rifle. I'm a little worried about some parts warping. Can anyone offer advice on the long trigger plate, trigger guard, and tang? Do I need to construct bracing for these parts? I had thought about packing the trigger plate and trigger guard assembled as a unit, but I'm pretty sure that's not the way to go. I'm about 2-3 weeks away from this attempt. I may try to post some photos.

Case harden only the triggers and not the bar.The bar will have to be drilled for the rear tang screw and for the trigger guard.
I doubt if any of these old guns had case hardened parts.

Bob Roller

[jerrywh]

Personally I would not case harden the trigger guard or the tang and butt plate, But if you do, do it before you inlay them and keep your quenching temp down to around 1350°. or even as low as
1250 ° f .  Make sure the long pieces go into the quench vertically. They will warp some no matter what you do.  That's my experience.

[D. Taylor Sapergia]

I've only done this a couple of times, and both were Hawken rifles' parts.  I did get a bit of warping with buttplates , trigger plates, and toe plates.  I needed to do a bit of extra inletting, but it all worked out in the end.  Blocking parts is, I think, how to avoid warping.

[rich pierce]

One of the challenges is that it’s likely that back then they case hardened wrought iron or mild steel. So the core stayed ductile with a short soak In the pack , say half an hour. Then parts could be bent if needed without breaking. Nowadays we seldom use mild steel for these parts so they would through harden. Then they would be quite brittle even if drawn to 450 degrees and would not cold bend.

When I case harden I wrap with 1/16” black wire (mild steel). If it snaps when I unwrap it I’m sure I got a deep case hardening. An hour of pack hardening at heat does it.

I spark test “steel” on my grinder and can predict pretty well whether it can harden through or needs case hardening.

[Clark Badgett]

Does anyone know how 1018 handles case hardening?

[rich pierce]

Does anyone know how 1018 handles case hardening?

If thick enough and not case hardened at temp more than half an hour and at least 1/8” thick I’d think it could be straightened after hardening I’d needed. But I’d not bend it at the screw holes specifically.

[Bob Roller]

Does anyone know how 1018 handles case hardening?

All of my set triggers with FEW exceptions are 1018 and case hardened and so far
no problems with wearing out have been reported.1018 is very amenable to any
commonly used case hardening compounds like Brownell's or Cherry Red or KASENIT
if you're lucky enough to have some.It also is easy to work with tools commonly seen in
a home work shop.
Bob Roller

[RAT]

Just to clear up any misunderstandings...

The rifle is essentially finished. I'm finishing up the stock shaping this week. The only parts left to inlet are the barrel key inlays. After that it's sanding to get ready for stock finish.

Why bone/wood charcoal color case hardening? The pictures Herb posted in the past of the Kit Carson rifle show that these late Gemmer period Hawken rifles were finished in this manner. I plan to rust blue the barrel assembly (barrel, rib, and forward pipes). All other metal will be color case hardened.

I understand the need to harden the triggers themselves. What I'm looking for here is mostly color.

[rich pierce]

If color is the goal, a short pack soak at desired temp should suffice and not case harden very deep.

Alternatively one can case harden using one of the powders mentioned above and quench in a solution of potassium nitrate. Depending on concentration of potassium nitrate the color may vary. The more concentrated, the more blue tones in my limited experience.




Last and least durable, one can use a propane torch to give tempering colors to the steel parts.