Another case hardening method

[Mattox Forge]

I built a cannister like Larry Potterfield had on his Midway case hardening tutorial on YouTube. It has a sliding trap bottom. I use a kiln to heat and soak the loaded cannister. The fork lets me carry it out of the kiln and set it on the quench barrel. I used a lot of bone charcoal and put sodium nitrate salt in the quench water. The case colors are very dark blue. The pictures are pretty poor, I'll take some better ones in sunlight. The plate stayed straight, i set it on edge in the cannister, and it seemed to plunge in that way. I am pretty pleased with this Baker build, as I have been able to learn some new techniques.

Mike

[rich pierce]

Looks like a pro-level setup. Very nice setup and results.

[bama]

Very nice indeed. Case coloring is something I am starting to do and I have found out that you need a good setup to get good results. I think you have accomplished that. Congratulations.

[Daryl]

Looks pretty good. How did the Bris get so much browns and yellows?

[Mattox Forge]

Thanks everyone for the kind words.

Looks pretty good. How did the Bris get so much browns and yellows?

I think they had a lower percent of bone/nitrates in the pack and the quench water. I had a lot of sodium nitrate salt in the quench bath. An earlier test I did had a 1/3 mix of bone and wood charcoal, mostly wood, and nothing in the quench water, and I got a lot more brown and red, with clear spots where the quench water washed around the edges. In this heat, I packed 100% bone charcoal around the parts, and used the wood as a filler above and below the part layer.

In the earlier test I also dropped the test lock plate in bolster side first, and it warped. You can see the browns and blues, and the clear areas where the quench water flowed around the edges and through the holes.


In the latest heat, I dropped everything in edge wise, that is on the edge I wanted to keep from warping. I will have to play around with the charcoal mix and the quench water to see how the colors are affected.


Mike

[Daryl]

THAT one looks GREAT!
Lighting matters.

[44-henry]

Potassium nitrate added to the quench will add a lot of blue to the parts. Not sure about sodium nitrate. I have found when you get much over 1450 F the colors tend to be pretty dark. The higher temps due increase the speed of carbon penetration though. When I do it I shoot for a 50/50 mix of wood to bone and wrap the parts in steel wire in a rough grid pattern. This seems to produce good colors, in part because it holds the charcoal against the part longer during the quench.

[Ben I. Voss]

Very cool. Looks like fun!