Post by drhenley on May 12, 2019 10:53:31 GMT -5
I'm going to give a little info about knife steel. There are myriads of choices nowadays, but I'll stick with the ones that aren't made of unicorn teeth.
Some terms:
Edge retention: the ability to stay sharp.
Edge stability: the ability to take and hold a fine edge without rolling or chipping.
Toughness: the ability to take abuse without breaking
Dimensional stability: the ability to undergo heat treating without warpage.
Carbon Steels
1075 - can you say "Cheap Chinese"?
1084 - pretty decent carbon steel, probably what Sed's grass shears are made of. Can be heat treated without fancy equipment. Recommended for beginners.
1095 - what the USMC Ka-Bars are made of, which are legendary for their toughness and edge retention. Can be heat treated at home, but to get the maximum hardness and toughness (like the Ka-Bars) you might want to send it off.
52100 - developed for ball bearings, so excellent edge retention and toughness. Great edge stability, and not too hard to sharpen. Considered better than 1095. Easy to heat treat.
O1 - The "O" is for oil hardening. They make dies from O1 for stamping out tool steel parts, so tough and hard is an understatement. See the video below for an insane torture test on an O1 knife. But as someone said, it will rust as you are watching it. Tendency to warp when heat treated. But makes a damn good blade. Can be heat treated at home. Edge stability and retention are excellent.
D2 - Near stainless, edge retention is superb, but not nearly as tough as O1. It's a bear to work. I had my fling with D2 and now I'm moving on to something easier to work. This is an air hardening steel, and has very specific instructions for heat treating. But it has good dimensional stability. And also need cryo treatment to get the best results. Need a reputable service to do the heat treating.
A2 - Sort of a happy medium between O1 and D2. The "A" is for air hardening. Like D2 it has good dimensional stability. Good edge retention, and toughness. Like D2, you don't want to heat treat this at home.
Stainless Steels
420, 440A (see 1075)
440C - Used to be considered premium blade steel, and at one time most quality mass produced hunting knives were made of 440C. Compared to 1095, O1, or D2, it's not in the same class, but still makes decent blades. Not terribly difficult to heat treat, but does require tighter temperature control.
440B - Similar to 440C, but with inferior edge retention and superior toughness.
154 CM - Upgraded version of 440C with added molybdenum and slightly less chromium. Superior to 440C in all categories except ease of sharpening.
AEB-L - Very misunderstood, and therefore one of the most underrated stainless steels. Usually compared to 440C because of the carbon content. But the big difference is that AEB-L has very small, very hard K2 chromium carbides, while 440C has large K1 chromium carbides, which limit how fine an edge 440C can take and also makes it harder to sharpen. AEB-L is easy to sharpen and can take a very fine edge. It is the toughest stainless steel, on par with 1095 and O1, but edge retention is not that great until you get up to Rockwell 63 or so, and then it starts to shine. Also, because of the very small carbides, it can take a mirror polish. Very specific heat treating, best done by professionals.
This is why Chris makes knives out of O1:
Some terms:
Edge retention: the ability to stay sharp.
Edge stability: the ability to take and hold a fine edge without rolling or chipping.
Toughness: the ability to take abuse without breaking
Dimensional stability: the ability to undergo heat treating without warpage.
Carbon Steels
1075 - can you say "Cheap Chinese"?
1084 - pretty decent carbon steel, probably what Sed's grass shears are made of. Can be heat treated without fancy equipment. Recommended for beginners.
1095 - what the USMC Ka-Bars are made of, which are legendary for their toughness and edge retention. Can be heat treated at home, but to get the maximum hardness and toughness (like the Ka-Bars) you might want to send it off.
52100 - developed for ball bearings, so excellent edge retention and toughness. Great edge stability, and not too hard to sharpen. Considered better than 1095. Easy to heat treat.
O1 - The "O" is for oil hardening. They make dies from O1 for stamping out tool steel parts, so tough and hard is an understatement. See the video below for an insane torture test on an O1 knife. But as someone said, it will rust as you are watching it. Tendency to warp when heat treated. But makes a damn good blade. Can be heat treated at home. Edge stability and retention are excellent.
D2 - Near stainless, edge retention is superb, but not nearly as tough as O1. It's a bear to work. I had my fling with D2 and now I'm moving on to something easier to work. This is an air hardening steel, and has very specific instructions for heat treating. But it has good dimensional stability. And also need cryo treatment to get the best results. Need a reputable service to do the heat treating.
A2 - Sort of a happy medium between O1 and D2. The "A" is for air hardening. Like D2 it has good dimensional stability. Good edge retention, and toughness. Like D2, you don't want to heat treat this at home.
Stainless Steels
420, 440A (see 1075)
440C - Used to be considered premium blade steel, and at one time most quality mass produced hunting knives were made of 440C. Compared to 1095, O1, or D2, it's not in the same class, but still makes decent blades. Not terribly difficult to heat treat, but does require tighter temperature control.
440B - Similar to 440C, but with inferior edge retention and superior toughness.
154 CM - Upgraded version of 440C with added molybdenum and slightly less chromium. Superior to 440C in all categories except ease of sharpening.
AEB-L - Very misunderstood, and therefore one of the most underrated stainless steels. Usually compared to 440C because of the carbon content. But the big difference is that AEB-L has very small, very hard K2 chromium carbides, while 440C has large K1 chromium carbides, which limit how fine an edge 440C can take and also makes it harder to sharpen. AEB-L is easy to sharpen and can take a very fine edge. It is the toughest stainless steel, on par with 1095 and O1, but edge retention is not that great until you get up to Rockwell 63 or so, and then it starts to shine. Also, because of the very small carbides, it can take a mirror polish. Very specific heat treating, best done by professionals.
This is why Chris makes knives out of O1: