- Joined
- Sep 19, 2001
- Messages
- 8,968
So, I quenched a knife for the first time yesterday. It was a 14" Old Hickory that I had cut a clip into and reshaped the handle a bit. First I got the handles off, easy peasy. I put it in my vertical tube forge thing - 16" diameter, 24" tall, 2" kaowool/satanite/itc lining, with a 24" x 4" ID capped pipe hanging in the middle as a baffle *also have one in ss for salt, eventually* Soaked for 20 minutes at 1250 with some cardboard in the pipe; shut it off and let it cool slowly. That seemed to work fine, the files bit in deep. I could sharpen it with a file beforehand, OHs are fairly soft, but it was a marked difference nonetheless.
Screwed around with the profile with a cut off wheel & 2 x 42. A couple minutes in diluted muriatic acid to clean off the steel, washed it, then scotch brite for the light gray patina. It looked ok, so sanded it with 220, wiped it off with alcohol, covered it with too much satanite, dried, and tried to soak it at 1430-ish. My controller was trying best it could, but I need to refine the gas metering. Too much gas plus the slow, low buck controller had me stepping in to try and hold temp, which went from 1420-1450 during the 10 minutes I let the blade soak after coming up to temp. I then quenched into a tank of 5" square tubing on end with 7 quarts of Parks 50 and some water. It was supposed to be 2 gallons, hence the addition of water to give me the fluid depth I was hoping for. Ended up dropping the damn thing in the tank, but no visible damage other than a ding in the tip.
Cleaned off most of the satanite, which held fiercely and did not pop off. Stuck it in the oh so accurate kitchen oven at 400 for an hour, didn't fully harden closer to the ricasso anyway. To see what I did get, I sanded from 220 to 1200, using some hot apple cider vinegar a couple times to etch. Polished with some 2.5 micron silicon carbide paste, and then 0.5 chromium oxide. Sanding was going well until I noticed low spots in the grind. At first I figured it was a lousy grind on a cheap knife, then I looked down the edge and saw how the entire thing was rippled. I went ahead with the grit progression for practice, that was the point of the knife anyway. There is also a slight curve to the right, maybe from when I dropped it in the middle of quenching. Couldn't tell when it still had the clay on it.
While a little thin in spots, I got a little cloud and a bit of pattern in a small hamon. The uneven edge just makes it impossible to see in most spots without perfect angle & light.
I have figured out so far to work on my propane burner some more, buy one of those Omega controllers with ramp/soak that I was looking at a couple hours ago, use less satanite (1/8" thick, but too far down), not to clay a 14" blade on your first try hardening anyway, take a closer look after quench and have a straightening jig handy, order more Parks, wear long sleeves. And I'll throw in a couple normalizing heats on the other OHs I grind on.
Still I'm wondering about the rippled edge. Even though the knife was dead dull, I guess it was too thin at the edge. Suggestions? I have a dozen more to practice on, none this long, and they only get cheaper to replace. I like to start off with a spectacular failure, the only way left to go is up.
as long as I don't set the garage on fire
Screwed around with the profile with a cut off wheel & 2 x 42. A couple minutes in diluted muriatic acid to clean off the steel, washed it, then scotch brite for the light gray patina. It looked ok, so sanded it with 220, wiped it off with alcohol, covered it with too much satanite, dried, and tried to soak it at 1430-ish. My controller was trying best it could, but I need to refine the gas metering. Too much gas plus the slow, low buck controller had me stepping in to try and hold temp, which went from 1420-1450 during the 10 minutes I let the blade soak after coming up to temp. I then quenched into a tank of 5" square tubing on end with 7 quarts of Parks 50 and some water. It was supposed to be 2 gallons, hence the addition of water to give me the fluid depth I was hoping for. Ended up dropping the damn thing in the tank, but no visible damage other than a ding in the tip.
Cleaned off most of the satanite, which held fiercely and did not pop off. Stuck it in the oh so accurate kitchen oven at 400 for an hour, didn't fully harden closer to the ricasso anyway. To see what I did get, I sanded from 220 to 1200, using some hot apple cider vinegar a couple times to etch. Polished with some 2.5 micron silicon carbide paste, and then 0.5 chromium oxide. Sanding was going well until I noticed low spots in the grind. At first I figured it was a lousy grind on a cheap knife, then I looked down the edge and saw how the entire thing was rippled. I went ahead with the grit progression for practice, that was the point of the knife anyway. There is also a slight curve to the right, maybe from when I dropped it in the middle of quenching. Couldn't tell when it still had the clay on it.
While a little thin in spots, I got a little cloud and a bit of pattern in a small hamon. The uneven edge just makes it impossible to see in most spots without perfect angle & light.
I have figured out so far to work on my propane burner some more, buy one of those Omega controllers with ramp/soak that I was looking at a couple hours ago, use less satanite (1/8" thick, but too far down), not to clay a 14" blade on your first try hardening anyway, take a closer look after quench and have a straightening jig handy, order more Parks, wear long sleeves. And I'll throw in a couple normalizing heats on the other OHs I grind on.
Still I'm wondering about the rippled edge. Even though the knife was dead dull, I guess it was too thin at the edge. Suggestions? I have a dozen more to practice on, none this long, and they only get cheaper to replace. I like to start off with a spectacular failure, the only way left to go is up.
as long as I don't set the garage on fire
