CPM 154-CM oil quench question ????

Status
Not open for further replies.
you guys are right i was rude and am seriously sorry maybe i need to be a little less sensitive.

and yes 1234 that makes sense what you are saying about the heat treats on the crucible website

sshepherd i have been making knives for 2 years not very long.
 
chad2 said:
you guys are right i was rude and am seriously sorry maybe i need to be a little less sensitive.

and yes 1234 that makes sense what you are saying about the heat treats on the crucible website

sshepherd i have been making knives for 2 years not very long.
Click to expand...

That's a pretty classy move, chad2.:thumbup: It is very difficult to read intent through text. I sometimes find myself reading though responses 4-5 times to understand what angle folks are coming from. For the most part, I read replies for content and try to leave emotion out of it.... I have been misunderstood on many occasions.
 
I would use the slowest oil that you have or can get if you want to oil quench. 28 second from McMaster sounds good. Any oil is going to be faster than air, however if you get too fast of an oil you may crack or warp the steel. Slow oil, an interupted oil quench, aluminium plates, or still air should all work fine in general, if you test different methods you may find one has its advantages for the way you work and the results you want. Good luck and remember this is for fun!
 
ok then if i am going to heat to 1950 for 1 hour then air quench, does any one know what your initial RC is going to be at? also will plate quenching give me a higher RC?
 
for an air quench does the room temp matter like should i do it in a warm room like 70-80 degrees or should i air quench in 60-30 degrees will this make a difference?
 
chad2 said:
ok then if i am going to heat to 1950 for 1 hour then air quench, does any one know what your initial RC is going to be at? also will plate quenching give me a higher RC?
Click to expand...

The chart says 61 HRc after 1950. You MAY have a lower hardness by 1 to 2 points. So as quenched hardness will be somewhere between 59 and 61 HRc. Those heat treating instructions are generic. Knives are very thin compared to most other things made with the steels knifemakers use. They will cool quite quickly. You may not see any loss in hardness, but you might. You also may not see any gain with plate quenching, but you might. The reasons for plate quenching are more than just more rapid cooling. I'll quote Robert C. our resident retired metallurgist. "If you are using air hardening steels, but aren't plate quenching, you should be." If you don't want to buy plates, use air, or the slowest oil you can find. Canola oil might be a good start, and you can try it for a few bucks, unless it cracks your blade. Canola is not what you'd call a "slow" quenching oil. This heat treating thing is not as exact as its made out to be. A difference of one hardness point plus or minus your target hardness is pretty good until you get some practice with that steel, from that batch. If you use air quenching, I don't think 30 degrees one way or the other will make much difference, though room temperature is usually taken to be 68 to 72 degrees F.
 
Since CPM 154 is air hardening it will not make a significant difference if the air temp during the quench. A fan blowing onit will speed things up a bit but don't get too crazy or you might induce a warp. The HRC listed on the crucible website indicates oil quenching varies between 62-64HRC as quenched so air would be 1-2 points lower prior to tempering. That would put you at 60-62HRC then temper down to 58-59HRC depending on what type of knife you are using. The reason it is recommended to send out the CPM steel is that heat treaters have vacuum ovens, cooling systems and cryo set-ups. They have done all the homework and for $5 plus shipping it is hard to justify doing it yourself. But I understand wanting to do it all. But if you are worried about getting the most from your steel I suggest sending it out also.

As the Count pointed out, the data on the crucible web page is mainly for industrial purposes not knifemakers. Since we deal with much thinner cross sections oil can be problematic. You would not be happy trying to straighten out a horseshoe. Good luck and keep us posted on your progess.
 
chad, I don't know if you mentioned it or not- if your Paragon doesn't have an inert gas adaption, it's a good idea to wrap your blade in SS foil tool wrap when heating, leave it on during the plate quench. It'll be a lot more pleasant to finish after HT, and you can take it to a higher finish before HT. The foil will protect it.
 
A C Richards said:
Since CPM 154 is air hardening it will not make a significant difference if the air temp during the quench. A fan blowing onit will speed things up a bit but don't get too crazy or you might induce a warp. The HRC listed on the crucible website indicates oil quenching varies between 62-64HRC as quenched so air would be 1-2 points lower prior to tempering. That would put you at 60-62HRC then temper down to 58-59HRC depending on what type of knife you are using. The reason it is recommended to send out the CPM steel is that heat treaters have vacuum ovens, cooling systems and cryo set-ups. They have done all the homework and for $5 plus shipping it is hard to justify doing it yourself. But I understand wanting to do it all. But if you are worried about getting the most from your steel I suggest sending it out also.

As the Count pointed out, the data on the crucible web page is mainly for industrial purposes not knifemakers. Since we deal with much thinner cross sections oil can be problematic. You would not be happy trying to straighten out a horseshoe. Good luck and keep us posted on your progess.
Click to expand...

yes makes a lot more sense, no oil quenching for me :D
 
If you have the information directly from Crucible that would be the wise method to follow. Call them and ask them directly and then return and report on all the details :)
 
Chad2 the one thing I can say about what you are looking for is to take good notes about what you are doing. That way you can repeat the results when you find what works for you.

I can tell you what works for me and you may not get the same response, leading you to believe I mislead you. My oven at 1950 is not going to be the same as your oven at 1950. I don’t know about your oven but mine is not certified and tested to be plus or minus a couple degrees. Same thing goes for tempering the blades. I use the temps and times that work for what I want and that I can repeat in my shop.

I work with thinner blades because I make small and mid-sized folders most of the time and have good repeatable results plate quenching. The plates help me keep things flat and they work for me. I have not oil quenched CPM-154 or 154-CM and have no opinion on how that works.

That being said, most of the information I have read on Crucibles’ website is about hardening their steel is in a one inch thickness. We need to adjust that somewhat to what works for the thickness we are using to obtain the best result we are looking for. Testing the performance of your blades and good notes about what you did will help much more than any example of “what works for me” I can give you.

With my thin blades in CPM-154 I get about 62 as quenched. I put them in liquid nitrogen overnight 8 -12 hours or more depending on when I get back in the shop and I am at about 63. Temper at 475 on my oven gets me about 60. I can adjust the temp for a softer or harder blade if needed. And yes I check with a hardness tester to make sure my equipment is working properly and I didn’t mess up or forget something along the way.

Try a few things if you want and did I mention “keep good notes” so you can do it again if you like it.
 
You want a relatively fast quench.

Roman Landis talks about quench speeds in stainless as well as Verhoeven. This isn't simple steel, so it isn't as simple as just getting under the nose. If you're loosing a couple hardness points, I wonder what structures you're forming?

Oil quench it for best results if your application isn't too prone to warp. Slow oil, interrupted quench after probably about 10 seconds. You may find a good plate quench is almost as fast and a lot straighter and cleaner.

The rapid quench will improve corrosion resistance and reduce retained austenite. You're forming less chromium carbide on the way down and maintaining higher strain energy going into Ms.

I'd also go directly into cryo or dry ice as a part of the quench, always keep it cooling until you reach Mf.

It is a poor assumption that heat treaters you're sending your work too have done their homework and are trying to make the best blade possible. They're very concerned about risk of warping and cracking, and less concerned about things that are difficult to see and measure and may tend to lean towards a very conservative (slow) quench.

I have used a very well known heat treater that is very respected and gotten poor results.

I have had good results at Peters, although I talked to them about what I wanted before using them.
 
Aluminum plates will speed the quench as will a fan on low blowing down the spine of the blade lengthwise. What works for some might not work for you, but i would definitely agree with noting your processes to get repeatable results. The slightest variation might make all the difference in the world. CPM 154 is a pretty complex steel, as has been said, but can produce a very nice knife. Hopefully with all the information presented here, you find what works for you, Good luck!
 
Chad,
I would have thought that my closing the other thread where you were discussing this would have calmed you down. Please don't take the answers and advise as being rude, we are only trying to help. You are new to the forums ( although you post about three times a day), and we all need to get used to each other . Thanks for the apology.

As to your reference to the Crucible site and its mention of quenching CPM-154 in oil, they are giving industrial standards for large section work. We are knifemakers - we work in small, thin, pieces of steel. These will warp and break if quenched as suggested for larger materials. 1095 is a water quench steel on many charts...but you will find few here who will recommend it to a new maker. There is a huge difference between "Reading" some information, and "Understanding" it. The great thing about Bladeforums is that there are many here who will share their experience and knowledge with a new maker. The learning curve is a lot faster if one listens to those who do it daily.

In the thickness of a CPM-154 blade, a plate quench with a follow-up cryo treatment will get very low RA and high hardness. You will have to temper it back a good bit to leave it at a working hardness. you will be loosing no hardness points.

If you want to make your head spin, read Roman Landes threads and books on metallurgy and knife steel. The long and short is that there is too slow a quench as well as too fast. Just like Goldilocks, "Just Right" is the far better choice. If one is not sure where "Just Right" is, err on the side of slower, not faster.
 
thank you everyone for the info

looks like i will not be stainless steel wrapping it because i would like a bit faster quench because i am going to be fan quenching it.

ok i am going to heat to 1425 for 10 mins ramp to 1950 for 1 hour then floor fan quenching it untill cool to touch then dry ice over night then tempering at 550 degrees for 2 hours twice. my aim HRC is 59-61.
 
chad2 said:
thank you everyone for the info

looks like i will not be stainless steel wrapping it because i would like a bit faster quench because i am going to be fan quenching it.

ok i am going to heat to 1425 for 10 mins ramp to 1950 for 1 hour then floor fan quenching it untill cool to touch then dry ice over night then tempering at 550 degrees for 2 hours twice. my aim HRC is 59-61.
Click to expand...

You might be surprised how severe the decarb and pitting will be after a long soak at high temp. I think you'll regret not using the foil.

You can plate quench through the foil. You put the seams to the side so they don't interfere with the plates making solid contact. I'm sure the plate quench is faster than bare steel and moving air. :thumbup:
 
change of plans i am using stainless steel wrap and i am plate quenching i have just obtained two 1" thick aluminum plates :D
 
i have a couple more questions. is a 1 hour soak time to long because i have been reading and most people are staying aroung the 30 min soak time.

is 1 hour to long at 1950 degrees?

also when doing a cryo can i just through the blade into an ice chest with dry ice in it? or do i have to do something else?

i cant remember where i read it but i heard of a guy adding something else to his dry ice to make it colder. but maybe i am remembering wrong.
 
Last edited:
Status
Not open for further replies.
Back
Top