Thank you folks for your comments. I have done a bit of blacksmithing, for about 30 years, but have never tried making lock parts, other than springs. I have done more than a bit of hardening and tempering, including case hardening more than a few frizzens, hardening and tempering quite a few knives, tools, and other assorted items.
This lock is an old Robbins lock from the 1970s, so there are no pictures or replacement parts to copy. The old frizzen is worn down to the point that the edges of the frizzen are so sharp they will cut my hands, if I'm not careful. Conversely, the internals of the lock appear to be near new, though that lock has been used, quite a lot over the years.
Clint,
Thank you for that information. That is what I was looking for.
My plan is to use a high carbon steel railroad spike, for the body, and forge weld a piece of file
steel to the face of the frizzen. I have also considered using mild steel and pack hardening the entire part. HC spikes contain about 3 points of carbon, and should provide a strong body and durable base for the hard face of the frizzen, if I go that route.
Charred, crushed cow horns in an eggshell mix? That one is new to me, though I have heard of charring and crushing peach pits, to add to the charcoal in the pack.
What ratio of charred horn/eggshell, to charcoal do you recommend?
I do appreciate everyone's help.
J.D.