O1 quenching

Deering Knives

Deering Knives

Joined
Jun 9, 2014
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132
Question about heat treating stock removal O1 knives. Currently I'm using peanut oil heated to about 120-130F, kiln is at 1490F soak for 20 mins. I am noticing that my blades 3/32" - 5/32" thick, 8"-10" long almost always have warping. Will using a commercial type quenching oil help? I also would like to find a good source for these medium cooling oils such as parks AAA. I am spending too much time straightening blades and I really don't like doing an interrupted quench to fiddle with the blade during the crucial cooling time. tips? sources? other options for oils that I can actually find. I know I shouldn't be using a parks 50 or brownells tough quench because from what I understand, both are too fast for O1. thanks.
 
Are you doing a stress relief cycle before austenizing? The "interrupted quench" that you can do in order to straighten by hand just means that you need thick gloves and temps somewhere around the Ms point. Also, with 3/32 thick blades, you might want to think about grinding them after you harden. As for too fast, yes #50 is, but Tough Quench may be the same speed as AAA, fast, but not nearly as fast as #50.. it is repackaged Houghton Houghton Quench Q, which is an 11-13 second oil depending on what temp you use it at. At 120 or 180F it is 13 second. At the sweet spot at 150F, it is 11 second. #50 is 7-9 second oil and can be used at normal room temperature. It has about half the viscosity of AAA. You can also get the medium speed stuff from McMaster Carr. It is a fair bit goopier than Tough Quench. I have it for Cru Froge and O1, Especially thin blades and #50 for my fast stuff like W2 and 1084.
 
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jdm61 said:
Are you doing a stress relief cycle before austenizing? The "interrupted quench" that you can do in order to straighten by hand just means that you need thick gloves and temps somewhere around the Ms point. Also, with 3/32 thick blades, you might want to think about grinding them after you harden. As for too fast, yes #50 is, but Tough Quench may be the same speed as AAA, fast, but not nearly as fast as #50.. it is repackaged Houghton Houghton Quench Q, which is an 11-13 second oil depending on what temp you use it at. At 120 or 180F it is 13 second. At the sweet spot at 150F, it is 11 second. #50 is 7-9 second oil and can be used at normal room temperature. It has about half the viscosity of AAA. You can also get the medium speed stuff from McMaster Carr. It is a fair bit goopier than Tough Quench. I have it for Cru Froge and O1, Especially thin blades and #50 for my fast stuff like W2 and 1084.
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Thanks! I'm not doing a relief cycle. I only do shaping and drilling before HT. I do all bevel grinding after. I was looking at Mcmaster carr 28 second or 11 second. I was considering the 28 second oil but am not really sure if that is too slow. Will a relief cycle help fix the warping issue? I've also considered doing that.

As far as the "interrupted quench" goes, it is hard for me to figure out what the right time to pull the blade out and being able to accurately gauge the temp of the blade and check for straightness on a truly flat surface. Eye balling it doesn't seem to be accurate enough for me because when I move to the next step I make sure my blades are dead straight, I use glass to check for any gaps between the blade and surface for dead flatness.
 
to be in the ballpark: agitate for 6-7 sec. and remove the blade
it will be still wisping smoke, not much, and not yet wet with oil. you will feel the blade stiffening as you approach the Ms...she will "tell" you to stop forcing it straight.
After this you will be doing the last tweaks between tempering cycles (at tempering temperature)
 
O1 is a deep hardening steel. Every oil will manage to harden it.
That said a commercial quenching oil, medium speed will be the best. A vegetable oil (canola, olive, sunflower, peanuts...) will do fine.
Transmission, hydraulic, motor oil etc... are to be avoided for serious health concerns from their fumes.
 
stezann said:
O1 is a deep hardening steel. Every oil will manage to harden it.
That said a commercial quenching oil, medium speed will be the best. A vegetable oil (canola, olive, sunflower, peanuts...) will do fine.
Transmission, hydraulic, motor oil etc... are to be avoided for serious health concerns from their fumes.
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so... the mcmaster carr 28sec oil will be best? I'm not hip to knowing a lot about speed categories of oil.
 
I've been doing 1200 degrees for two hours, then letting it cool in the kiln to below 900, then out of the kiln. The procedure is listed on about any data sheet you can find for O1.
 
Couple more things on the checklist are dipping straight in the quench and using either a dunking (like jigging a lure) motion or slicing like you're cutting the oil. Vertical quench works very well for me.
Interrupted quench done right doesn't compromise hardness, AFAIK. As stezann says, a little smoke is the high end of ok, and looking wet with oil is the low end.
 
thanks guys. I've come to the conclusion that I will do a normalizing cycle.

Is it necessary to pull out at 900F? I planned to just set it to 1200 and let it cool over night so I can finish up for the day. I generally cut out and prepare a kiln full and HT at the end of my work day. I don't want to be up all night nor do I want to try and normalize the next day?

Also, I'm still so confused why no one will just recommend a good professional grade quench oil specifically, and the source? I know peanut oil is fine, I've been using it for a year now. It works, but I want "the best". Not trying to sound aggressive, I'd just like an answer from some of the many helpful members. Thank you!!
 
Parks AAA is probably the most popular engineered quench oil for O1. Source....Maxim Oil Fort Worth Texas
 
Deering Knives said:
Thank you very much. Maxim oil! Will look into it.
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Yes Maxim oil is great !! If they don't have the AAA they have there own brew for O1 so if they are out of the Parks ask about it. Don't quote me but I think its Durotherm . I have it at my shop and it works great on O1 . I was having a few thinner blades warp on me when I used Mcmasters and also the steel supplier was unknown . The steel was supplied by my client and for what its worth it could have been something else but it did harden properly just warped.
 
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