Hardening the Chakma

Joined
May 24, 2001
Messages
609
I fired up the one brick forge yesterday - here are the results.

I took 2 chakmas, one larger one from a villager (grinder finish, and one from a GH khukuri set. I didn't want to risk any of my HI ones til I had the method down.

Methodology
1) remove handle
The GH chakma had a horn handle and small blade. I had already removed the blade with the bioling water method and polished it, so it was in OK shape.

The villager Chakma still had the grind marks and was still in the wood handle. A few seconds of heat on the blade from a propane torch softened the laha enough to remove the handle with a pliers.

2) heat treat and quench
I heated both blades to non-magnetic in my one brick forge. Both blades were quenched in tap water until cool enough to handle bare-handed.

Results
1) I tested the two blades on several pieces of flint I got with a firestriker.

The villager made a few small sparks, but would still be difficult to light a fire with.

No sparks at all from the GH chakma.

After testing the blades, I put the handles back on (I heated them on te barbeque I already had going). This part was way easier than expected. Chakmasa went back together with no problem.

Other observations
I filed and sanded the villager chakma after it was reassembled. While finishing it, I discovered a flaw in the blade. It went completely thru the blade (right to left), and extended up from the "edge" for about 3/16 inch. At this point it branched and runs parallel to the blade, about 3/8" in each direction. This parallel flaw does not appear to extend thu the thicknedd ot the chakma.

There are three potential causes for this flaw. The first possibility (unlikely) is that there was a forging flaw I had not observed before refinishing the chakma. the second (more likely) possibility is that the flaw is the result of a stress riser from the grindmarks. Wayne Goddard mentions that this can happen in his book "The $50 Knife Shop" :( I suspect that this may not be a problem with an HI Chakma, since they are fully finished.

Next time I'll:
1) I'll normalize and anneal the steel before hardening.
2) finish to remove grindmarks before hardening.

Hope this is of interest to some of you.

Pat
 
Joined
May 9, 2000
Messages
29,205
I was actually kind of amazed to see apost on this forum. It had been a couple of months.

Thanks for the report. I found it to be very interesting indeed.
 
Joined
May 24, 2001
Messages
609
:D Thought it might be interesting enough to stir up some activity. I cross posted it here and at HI. Thanks for responding!

Pat
 
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