-
The BladeForums.com 2024 Traditional Knife is available! Price is $250 ea (shipped within CONUS).
Order here: https://www.bladeforums.com/help/2024-traditional/
heat treat?
- Thread starter jersey127
- Start date
- Joined
- Mar 19, 1999
- Messages
- 620
Here is the basics, Heat the steel up until it is a dull cherry red, or better yet heat until a magnet no longer sticks to it. Quench the blade in some type of light oil, like veggie oil, or old motor oil, which has been warmed to approximately 140degrees. Then the easiest way to temper the blade is to put it in the kitchen oven for about 2 hours at around 400 degrees. It is good to let the blade cool and temper it at least one more time. It can get more complicated, but this is the basic idea. Do a search and you will find a lot of information on heat treating 0-1. About a year and a half ago I asked the same question at least a couple of times.
Kyle Fuglesten
Kyle Fuglesten
Yes, and:
When quenching the steel in the pre-heated oil move it back and forth in a cutting motion, not side to side. While doing this count to about seven seconds and pull the blade. If it smokes but does not flame (the oil on fire) you should be finished with the quench. If it flames quench for another second or two but do not quench below a point where the oil on the blade will not smoke when you pull it. You would like for the tool steel to be at about 350 F. when pulled from the quench.
Have your temper oven pre-heated ahead of time so you can put the steel in it before the steel cools below 125 F.. Do not allow the steel to fall below 125 F. before the first temper. For all temper sessions thereafter allow it to cool to room temperature before tempering.
Roger
When quenching the steel in the pre-heated oil move it back and forth in a cutting motion, not side to side. While doing this count to about seven seconds and pull the blade. If it smokes but does not flame (the oil on fire) you should be finished with the quench. If it flames quench for another second or two but do not quench below a point where the oil on the blade will not smoke when you pull it. You would like for the tool steel to be at about 350 F. when pulled from the quench.
Have your temper oven pre-heated ahead of time so you can put the steel in it before the steel cools below 125 F.. Do not allow the steel to fall below 125 F. before the first temper. For all temper sessions thereafter allow it to cool to room temperature before tempering.
Roger
- Joined
- Nov 24, 1999
- Messages
- 4,981
Why don't you let it cool that much before tempering? I wipe mine off, grind off the scale, and occasionally leave them sit on the bench for a few hours till the oven is free. Only problems I've had so far is some grain growth where I overheated the tip trying to get the whole thing up to temp. Haven't done any extensive testing though besides normal/daily use.Am I not getting everything out of the steel that I could ?
As I understand, tempering quenched tool steel before it falls to a high of 150 F. or after it falls below 125 F. prevents proper development of grain structure. It is also mentioned in Bill Bryson's book about heat treating tool steels. If for some reason I can not temper immediately, I will put the steel in a approx. 200 F. oven until the temper oven is pre-heated for tempering.
Roger
Roger
- Joined
- Nov 24, 1999
- Messages
- 4,981
Thats interesting. I have an old (1930-40's, can't remember right now) American Machinist's Handbook that my grandpa gave me. I don't remember anything like that being mentioned in the section on heat treating, of course back then they didn't have the technology we do now to know as much about that stuff. I'll have to read some more,maybe something more current. Not saying I don't beleive you, its just got me curious now 
Matt,
I almost included that 'I think Tim Zowada was telling me the same thing last year on the phone', but I couldn't remember for sure it was he - so I didn't blame him for that in my previous post.
If you read anything contrary please let me know.
Roger
I almost included that 'I think Tim Zowada was telling me the same thing last year on the phone', but I couldn't remember for sure it was he - so I didn't blame him for that in my previous post.
If you read anything contrary please let me know.
Roger
- Joined
- Nov 24, 1999
- Messages
- 4,981
Sure, if I come up with anything definitive I'll be sure and post it. I remember some folks saying you shouldn't let the blade get cold before tempering as it increased chances of breakage if there was any stress or anything built up from quenching. I hadn't heard that it actually effects the final results though (provided nothing breaks). I can't imagine how the process your using would hurt anything though, I just hadn't heard of it before.
- Joined
- Aug 12, 2002
- Messages
- 2,259
99% sure Paul Bos mentioned a snap temper for steels like O1 before cryo(and before anyone asks him to do O1, he does NOT treat oil quenching steels). Don't want to get a bunch of people calling him and have him annoyed at me.
But not sure if he did this to avoid breakage, as I thought, or if it's because of that 125 deg nose as mentioned in this thread.
But not sure if he did this to avoid breakage, as I thought, or if it's because of that 125 deg nose as mentioned in this thread.
Matt,
As you stated it; what I mentioned may not have anything to do with breakage from simply cooling to ambient. However, it seems to me poor grain structure would contribute to that possibilty.
etp777,
I do snap tempers on all tool steels regardless of cryo. I have been advised by Paul not to do so on stainless before cryo - and now I do not. If not cryo'ing stainless I have snap tempered them and would continue to do so. Now that I have LN capability I plan to always cryo blades.
As a side note but still relative: I think I may be learning (not from experience, yet) that second and third tempers may best be performed at about 25 F. lower than the first temper. This, if true as I understand, provides all benefits of multiple tempers but better preserves the original RC of the first temper.
Roger
As you stated it; what I mentioned may not have anything to do with breakage from simply cooling to ambient. However, it seems to me poor grain structure would contribute to that possibilty.
etp777,
I do snap tempers on all tool steels regardless of cryo. I have been advised by Paul not to do so on stainless before cryo - and now I do not. If not cryo'ing stainless I have snap tempered them and would continue to do so. Now that I have LN capability I plan to always cryo blades.
As a side note but still relative: I think I may be learning (not from experience, yet) that second and third tempers may best be performed at about 25 F. lower than the first temper. This, if true as I understand, provides all benefits of multiple tempers but better preserves the original RC of the first temper.
Roger