Has anyone used Pop's 8670

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Feb 19, 2019
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Has anyone used pops 8670. With no place to plug in my oven I might have to use my little forge to HT a few pieces even if it is just for practice. The steel says it is their in house product. If anyone has used it does it come in a condition that is easy to HT from? After having issues with 80CrV2 I get nervous when I'm buying a bunch of steel that is just going to be a pain and take a lot of time consuming steps. It is a great deal though and I have been hearing good things about it.
 
i have never heard of it :rolleyes: why not use something already proven not to be a pain :cool:
I don't have a steel worked out for low alloy carbon steel and have been hear great things about 8670. 8670 would be perfect for large knives something I plan to do a lot more of soon. Can't lie, the price is something that makes it pretty attractive even though I know it doesn't make a huge difference in overall
 
Went to cut out two knives in Pop’s 8670 and my saw would not cut it. It’s supposed to be annealed.
 
Went to cut out two knives in Pop’s 8670 and my saw would not cut it. It’s supposed to be annealed.

Grind a notch where you want to start your cut. The steel is probably work hardened on the edges from a plasma cutter.
 
That did it thanks. I have never had that issue before.
The steel is cut to size with a Lazer which hardens just the very edge an angle grinder works best to cut it, they are annealed and very fine grain for heat treating, 8670 is similar to 5160 for heat treating, bring up to 1525 and quench, hold for a minute or two if you want. Then temper anywhere from 350-400 depending on use. I’ve made over 30 blades from Pops 8670 and they have all turned out really great. It is by far tougher than 1080, 80crv2, and slightly tough than 5160 with about .10-.15 % more carbon. It’s a known steel in the saw blade industry but make really good knives.
 
A good investment is a cheap abrasive chop saw. Just make sure the sparks go into a receiver box or something so they don't go where you don't want them.
They make a more expensive counter-rotating carbide cut off saws that makes no sparks.
 
The steel is cut to size with a Lazer which hardens just the very edge an angle grinder works best to cut it, they are annealed and very fine grain for heat treating, 8670 is similar to 5160 for heat treating, bring up to 1525 and quench, hold for a minute or two if you want. Then temper anywhere from 350-400 depending on use. I’ve made over 30 blades from Pops 8670 and they have all turned out really great. It is by far tougher than 1080, 80crv2, and slightly tough than 5160 with about .10-.15 % more carbon. It’s a known steel in the saw blade industry but make really good knives.

I would not say it’s inherently tougher then 80CrV2. In the Industry the smaller circle saws are made from 8670 and the bigger circle saws are 80CrV2. Even if it is a hair tougher for some reason I would consider 80CrV2 a better knife steel. I find it always heat treats beautifully and my customers seam to really love it.
 
I would not say it’s inherently tougher then 80CrV2. In the Industry the smaller circle saws are made from 8670 and the bigger circle saws are 80CrV2. Even if it is a hair tougher for some reason I would consider 80CrV2 a better knife steel. I find it always heat treats beautifully and my customers seam to really love it.
Actually it is inherently tougher, most likely due to the nickel in the steel that’s added to increase toughness and ductility while maintaining hardness. 80crv2 would have more wear resistance because of the vanadium so it comes down to how you want to maximize the steel, if you want a tough blade your better with 8670 then 80crv2 tempered down low, if you want the most wear resistance then 80crv2 might be a better choice, but that said 80crv2 is more costly and you can leave 8670 harder without as much concern of failure. Larrin did a graph with comparing toughness that I’ll attach below that shows there is a considerable difference in toughness. 46A08D3A-9A1E-4C38-A415-834921754F8A.jpeg
 
Actually it is inherently tougher, most likely due to the nickel in the steel that’s added to increase toughness and ductility while maintaining hardness. 80crv2 would have more wear resistance because of the vanadium so it comes down to how you want to maximize the steel, if you want a tough blade your better with 8670 then 80crv2 tempered down low, if you want the most wear resistance then 80crv2 might be a better choice, but that said 80crv2 is more costly and you can leave 8670 harder without as much concern of failure. Larrin did a graph with comparing toughness that I’ll attach below that shows there is a considerable difference in toughness. View attachment 1399769

It’s the toughest steel tested to date, and it has the widest acceptable temp range of any of the carbon or alloy steels in heat treat. Unless you are going for wear resistance, it’s hard to beat for hard use knives,
 
I have seen that graph in the past, that’s not what I was going off. I am going off experience from working with it. In an untempered state 80Crv2 seams to be tougher to snap then 8670 when I check grain sizes on coupons. If 80CrV2 has better wear resistance because of the vanadium. At what temper would wear resistance be the same and would 80CrV2 be tougher at that point? Not saying it is I’m just wondering if it would be. Look at the jump in L6 over a span of around 2RC. I wonder how 80CrV2 would look like in the 58-59 range.
 
I have seen that graph in the past, that’s not what I was going off. I am going off experience from working with it. In an untempered state 80Crv2 seams to be tougher to snap then 8670 when I check grain sizes on coupons. If 80CrV2 has better wear resistance because of the vanadium. At what temper would wear resistance be the same and would 80CrV2 be tougher at that point? Not saying it is I’m just wondering if it would be. Look at the jump in L6 over a span of around 2RC. I wonder how 80CrV2 would look like in the 58-59 range.

There isn’t enough vanadium in 80crv2 to form carbides. It’s there to prevent grain growth. Same with W2.
 
In CATRA testing, simple and low alloy steels get most of their wear resistance from harness of the matrix. We might notice some difference when cutting less abrasive materials because of the alloying, but it is a minimal contribution to edge retention. The best predictor is carbide volume, and secondly, maintaining toughness as hardness goes up to prevent chipping.
 
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