Summary of heat treat formula for Also's W-2

Tom Lewis

Tom Lewis

Joined
Feb 24, 2000
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I know that there are a lot of ways to do heat treating, but based on my very limited testing, this is what I have found out. This W-2 was received from Aldo a few days ago. I tested 1/8" pieces.

1. No prior heat treatment, just heated with a torch to past magnetic and quenched in Parks 50. RC 65. This piece was easy to break and had large grains.

2. 1600 for 15 min. Let cool 10 min. 1450 for ten minutes, let cool ten minutes. 1425 for ten minutes, let cool. Then heated with a torch to past magnetic and quenched in Parks 50. After decarb was removed, RC 64. If I removed more decarb it likely would have been RC 65. This was harder to break than #1, and had smaller grain structure than #1.

3. 1600 for 15 min. let cool 10min. 1450 for ten min. let cool ten min. 1425 for ten minutes, let cool. Then a one hour soak at 1200. Then heated with a torch to past magnetic and quenched in Parks 50. After decarb was removed, RC 65. This piece was really hard to break. The grain structure was very fine and better than #1 or #2.

Thanks to several on this forum who suggested I get All the decarb off in order to get a accurate RC reading.
In the future I plan to repeat this but use my Paragon instead of my torch, for the final heat before quenching.

I invite others to run these tests, or others and post your results.
 
How about eliminating the torch and doing the austenizing sep at say 1460 with a soak? Also have you though about turing foil for the thermal cycling and sub critical anneal steps and some kind of anti-scale compound for austenizing?
 
jdm61 said:
How about eliminating the torch and doing the austenizing sep at say 1460 with a soak? Also have you though about turing foil for the thermal cycling and sub critical anneal steps and some kind of anti-scale compound for austenizing?
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I asked Kevin Cashen about using foil while thermal cycling. He told me the foil might slow the cooling too much, resulting in undesirable structures. Something worth considering. I got an extra RC point when I got rid of the foil.

I get Rc67 consistently with a 5 min soak after cycles on 1650, 1550, 1450, the austentize at 1460. That's with my kiln in my shop with my thermocouple. I tested my setup. Others might be out 10f here or there. 1650 is higher than needed for W2, as 1600 is fine, but I already had 1650 programmed for 52100.
 
Willie, thanks for sharing. Have you broken a test piece to see the grain structure? I was amazed at how much finer the grain was after the steel soaked for an hour at 1200. The test piece was also much much harder to break than the others.
 
The 1200 soak made a huge difference for me as well. Still not enough. I'm hoping the new bar will be here soon and I csn see if that makes any changes
 
Well, that is what I do in part. I tend do the thermal cycles in the forge because I am using round bar W2, but I have found that the additional 1200 or so cycle after rough grinding pretty much eliminates warpage.My big concern would be using the torch especially on W2.
Tom Lewis said:
jdm61, good suggestions Why don't you do it?
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I started using the torch after a knifemaker who has used a lot of W-2. and whose blades I very much admire suggested using a torch. I have had lot's of experience using a torch for edge quenching. That's what I did to pass my JS ABS test. I know what color to look for.
Using the torch gave me a RC 65 and a very fine grain. I am happy with that.
jdm61, when I suggested you try your suggestions, I was not trying to be rude. My suggestion was for you to do some heat treatments with your suggestions then post the results. Report on the RC and break a sample piece to see the grain structure.
 
I get excellent temp control using a torch.

Tom, 65 Rc is still low for W2. Really should be hitting 67-68 before tempering.
 
Are there photos flying about to show "large" grain vs "small" grain? All of my practical experience with heat treating has been building dies, and following documented heat treat procedures based on the steel type, size and shape of the part. Never coloring outside the lines and breaking coupons, etc.

I've seen broken tools and dies of course, and have a general idea, but if there were examples out there to see, that would help me quite a bit. Actually, I saw the counterbores break out of a wear pad on a tooling plate the other day. It was hardened A2. The breaks were grey and matte in color. Almost no visible grain at all. The way it broke and how the tool is used led me to believe the plate was hardened and not tempered at all fwiw.
 
I have some altos w2 and while trying to dial in the heat treatment I made some coupons and normalized them 1650 10min 1500 10min 1350 for 10min cooling to black each time. I austenized at 1450 and 1470 and had a unexpected result. The 1450 had smaller grain but broke at 45 degrees and the 1470 had larger grain but broke 90 + 90 the other way 180 degrees. Both were tempered at 400. I don't have a hardness tester. Any ideas?
 
Ah. Okay. I have never even attempted to edge quench W2 as never saw the need/benefit especially with big blades and I have a slight to moderate red-green color blindness, so I don't trust my eyes to tell the color. Before I got my oven I was using a black iron muffle pipe and a thermocouple on my forge.
Tom Lewis said:
I started using the torch after a knifemaker who has used a lot of W-2. and whose blades I very much admire suggested using a torch. I have had lot's of experience using a torch for edge quenching. That's what I did to pass my JS ABS test. I know what color to look for.
Using the torch gave me a RC 65 and a very fine grain. I am happy with that.
jdm61, when I suggested you try your suggestions, I was not trying to be rude. My suggestion was for you to do some heat treatments with your suggestions then post the results. Report on the RC and break a sample piece to see the grain structure.
Click to expand...
 
Tom Lewis said:
Willie, thanks for sharing. Have you broken a test piece to see the grain structure? I was amazed at how much finer the grain was after the steel soaked for an hour at 1200. The test piece was also much much harder to break than the others.
Click to expand...

I thermal cycle the steel for stock removal knives when in bar form. A 1200f soak for 2h saves a lot of belts compared with not doing it. Spheroidized steel is much more machinable than pearlite. I haven't broken a bar in a few years now, and don't remember if I compared pearlite to spheroid structures. For a forged blade, I haven't done the subcritical anneal. Maybe I'll add that step. I haven't noticed any performance difference, but it certainly can't hurt.
 
jdm61 said:
Well, that is what I do in part. I tend do the thermal cycles in the forge because I am using round bar W2, but I have found that the additional 1200 or so cycle after rough grinding pretty much eliminates warpage.My big concern would be using the torch especially on W2.
Click to expand...

If the round bar you are using is Don's then there is the difference between your findings and Tom's.....Don's W2 and Aldo's are different. Don't ask me what makes it different but different it is. This is after 100 pounds of the original, first run of Aldo's W2 and well over 300 pounds of Don's W2.
 
Thanks for posting this information. I didnt want to start a new thread but I have been wondering, how many times can you normalize, harden, quench, and anneal a blade? Ive got about 30 hours invested in a batch of blades that wouldnt harden on two attempts, is it still possible to get good results on a third attempt?
 
timos- said:
Thanks for posting this information. I didnt want to start a new thread but I have been wondering, how many times can you normalize, harden, quench, and anneal a blade? Ive got about 30 hours invested in a batch of blades that wouldnt harden on two attempts, is it still possible to get good results on a third attempt?
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The tip will likely drop a bit each quench. You can repeat as many times as you like, but you will lose some steel to decarb every time, eventually getting too thin.
 
Interesting. I have only used Don's and saw the late John White austenize a large bowie blade at like 1425 in order to get a crazy hamon like we all want. I kmow that we are not supposed to believe in magic super steel, but this stuff comes close. :D
mike malosh said:
If the round bar you are using is Don's then there is the difference between your findings and Tom's.....Don's W2 and Aldo's are different. Don't ask me what makes it different but different it is. This is after 100 pounds of the original, first run of Aldo's W2 and well over 300 pounds of Don's W2.
Click to expand...
 
jdm61 said:
Interesting. I have only used Don's and saw the late John White austenize a large bowie blade at like 1425 in order to get a crazy hamon like we all want. I kmow that we are not supposed to believe in magic super steel, but this stuff comes close. :D
Click to expand...

Thats why I bought 2500 pounds of Don's W2...It's that good.
 
Mike Malosh, you clearly have more experience with W-2 than myself. Would you consider posting how you heat treat the W-2 steel that you have?
 
Tom Lewis said:
Mike Malosh, you clearly have more experience with W-2 than myself. Would you consider posting how you heat treat the W-2 steel that you have?
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Tom, I cannot hold a candle to Don Hanson in the W2 HT department but I have taken what he uses and only changed it a bit to my shop.

After forging I do a quick and dirty normalizing...which means I load all the forged blades in the forge when i shut it off for the day.

after rough grinding for HT (normally at 120 grit) I heat the forge up until it stabilizes at 1450, using a hand held PID. I just watch the colors of the cutting edge as personally I do not care about the spine. Its the cutting edge i care about. which BTW although I do not bring it out i get some nice natural hamon activity. I quench in Parks 50. They are pretty consistent at 67Rc

after the blades are cool I load them in the tempering oven at 425 let them set 90 minutes. pull them out, grind a few clean and Rc test I like 58 to 60 for my hunting blades. If it reads high then I bump up the temp to change it on the next tempering cycle. so basically two tempering cyles each 90 minutes...now in between cycles I do dunk them in water to cool them down fast so I can hold them.

Don kept things super simple and there was no reason for me to get fancy. I just followed what he put on here a few years back and adjusted for my shop....When i have talked to him it seems we have gotten the same results as far a hardness....His hamons are bitchin though for sure.
 
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