# 1095 brine quench help



## Heli (Apr 26, 2021)

Hi,

@Kippington, I have seen a video on how you quenched a 1095 knife in brine, without clay.

I would like to ask for your help on how is the process different when the blade is clayed.

Just for clarity, the video shows an interrupted edge quench from brine to oil.

Thanks in advance,


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## Heli (Apr 26, 2021)

Sorry should have mentioned, this is for everybody else with experience on this matter.

thanks,


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## Bensbites (Apr 26, 2021)

I have brine quenched 1095, If you clay it properly you can get differential hardening. if you clay it improperly, you can crack the blade. Quenching without clay with give you fully hardened blade. In the photo below, the bunka was quenched with out clay, and the gyuto was clayed.


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## Heli (Apr 26, 2021)

Bensbites said:


> I have brine quenched 1095, If you clay it properly you can get differential hardening. if you clay it improperly, you can crack the blade. Quenching without clay with give you fully hardened blade. In the photo below, the bunka was quenched with out clay, and the gyuto was clayed.




Thanks, I‘m looking for detailed directions on the interrupted quench, e.g. how many seconds in, out, when from brine to oil, etc. How not to get a negative sori.


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## Heli (Apr 26, 2021)

Here is the video from @Kippington, just to get an idea at the level of detail I’m looking for,


thanks again,


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## Kippington (Apr 26, 2021)

It depends on how thick you have the blank before the quench, how good the surface coating is on your knife is (if any), water temps, austenitizing temps... really a lot of variables.
Have you done it before?


Heli said:


> I would like to ask for your help on how is the process different when the blade is clayed.


The major difference is not submerging the spine as much as the edge, to control the the speed of the quench differently from the edge. Clay also works to achieve the same thing but via a different means.


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## Bensbites (Apr 27, 2021)

Heli said:


> Thanks, I‘m looking for detailed directions on the interrupted quench, e.g. how many seconds in, out, when from brine to oil, etc. How not to get a negative sori.


For what it’s worth, I highly recommend Latin’s book knife engineering. I also suggest a temp controlled kiln. Heat to 1475, hold for 10 min after the temp hits 1450. 1-2 seconds in the brine, 2-3 seconds in air, then into oil until ambient temp. 

radius all sharp corners to reduce the risk of cracking. .


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## Heli (Apr 27, 2021)

Kippington said:


> It depends on how thick you have the blank before the quench, how good the surface coating is on your knife is (if any), water temps, austenitizing temps... really a lot of variables.
> Have you done it before?
> 
> The major difference is not submerging the spine as much as the edge, to control the the speed of the quench differently from the edge. Clay also works to achieve the same thing but via a different means.



Yes, I’ve done it on a tanto, in water at 75F, not brine, austenizing temp of 1475F with a 10 min hold and it cracked. This was an uninterrupted quench and obviously too violent. Got a lot of sori, but obviously useless. 

This time around, I am planning to use an interrupted quench, brine at 120-130F, then oil at 130F, blade will be first completely covered with a thin wash of Satanite, then a little thicker, say not more than 1/16 thick near the spine for the hamon.

Maybe lower austenizing temp of 1450F. I don’t want to get a sori, maybe just a bit, since this is a short blade, not a katana.

I will keep an edge of .05 inch before quench.

How does these parameters sound?

I’m looking for details on the interrupted quench, timing of brine to oil and whatever other relevant steps during the quench.

thanks again,


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## Heli (Apr 27, 2021)

Bensbites said:


> For what it’s worth, I highly recommend Latin’s book knife engineering. I also suggest a temp controlled kiln. Heat to 1475, hold for 10 min after the temp hits 1450. 1-2 seconds in the brine, 2-3 seconds in air, then into oil until ambient temp.
> 
> radius all sharp corners to reduce the risk of cracking. .



Yes, thanks again, these are all great details of the quench. This level of detail is what I’m looking for. I assume you meant Devin’s book. And yes, I just got the book, my next step was to have a look in there as well. Didn’t get a chance yet. Just trying to educate myself and get other’s experience before my next attempt. I’m at the gathering info stage right now.

Kippington is doing an interrupted edge kind of quench that I thought was interesting and I believe helps keeping the spine from moving and causing the edge to crack. Was looking to hear his steps when working with a clayed blade.


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## Bensbites (Apr 27, 2021)

devin’s son Larrin wrote the book.

My understanding is that edge quenches are more stressful on the blade than a full quench.

I focus on kitchen knives, and grind after heat treat. I generally have 2.5-4 mmthick blades at to heat threat.


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## Heli (Apr 27, 2021)

Bensbites said:


> devin’s son Larrin wrote the book.
> 
> My understanding is that edge quenches are more stressful on the blade than a full quench.
> 
> I focus on kitchen knives, and grind after heat treat. I generally have 2.5-4 mmthick blades at to heat threat.



Yes, you are correct, I was thinking about his father, my bad.

Not sure to be honest, but I think Kippington’s edge quench hybrid kept the spine from producing a sori and didn’t create forces that would pull on the edge and create fractures.

He is cooling the spine as well, just not too fast and therefore less violent movement/transformation is eliminated. That and the combination of the interrupted quench then in oil, then in air does the trick i guess. Looks like he is trying to equalize the forces once he passed the curve nose. So I guess once he got the edge cooled in the first second down to 900F or so, he can take his time a bit and slow things down.

It is just my interpretation and I could definitely be wrong.


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## Kippington (Apr 27, 2021)

Unfortunately, you have it mostly wrong.

I am primarily controlling the rate of cooling, the formation of stresses is a secondary consideration.
If you want to minimise the sori, quenching in oil is your best bet... although it might result in a negative sori.


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## Heli (Apr 27, 2021)

Kippington said:


> Unfortunately, you have it mostly wrong.
> 
> I am primarily controlling the rate of cooling, the formation of stresses is a secondary consideration.
> If you want to minimise the sori, quenching in oil is your best bet... although it might result in a negative sori.



That’s pretty brief, all good man...

UPDATE:
On a second thought, may I suggest in the future you use the word “incorrect” rather than “wrong” it shows more class, not to mention it is offensive.

It’s totally fine if you don’t want to provide the information I asked for, please re-read my post, but let’s keep this classy, thanks in advance.

And I promise, I will never ask for your input again, that was probably my fault and I apologies if it felt to you as if I was trying to put you on the spot, not my intention.


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## Kippington (Apr 27, 2021)

Sorry. No offence meant, just answering in a hurry. It's 1am here.

It was a throw-away comment following on from your previous post.
Perhaps it wont be so bad if you read it directly after this:


Heli said:


> It is just my interpretation and I could definitely be wrong.


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## Heli (Apr 27, 2021)

Kippington said:


> Sorry. No offence meant, just answering in a hurry. It's 1am here.
> 
> It was a throw-away comment following on from your previous post.
> Perhaps it wont be so bad if you read it directly after this:



Fair enough, just for clarity, there is difference when I say, I could be wrong and you say, I’m wrong, big difference! May seem subtle...

Anyway, nice of you to appologise, no need to keep this going, cheers.


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## inferno (Apr 27, 2021)

it bends both ways at different times.


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## RDalman (Apr 28, 2021)

Aus at 794,7 c for 387,5 secs. Quench in 37,8 c 22% brine for 3,63 secs agitating 38 times 20 cm. Move into 138c oil over max 1,4 secs and keep there for 897 secs. Temper. 

This is for a 3,14 mm thickness blank with 37 my layer of wash clay (secret recipe) 

It may crack


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## Heli (Apr 28, 2021)

RDalman said:


> Aus at 794,7 c for 387,5 secs. Quench in 37,8 c 22% brine for 3,63 secs agitating 38 times 20 cm. Move into 138c oil over max 1,4 secs and keep there for 897 secs. Temper.
> 
> This is for a 3,14 mm thickness blank with 37 my layer of wash clay (secret recipe)
> 
> It may crack



Almost there, you forgot the tempering cycle details. Keep up the good work and should be proud of yourself for providing such great feedback. Really makes me want to post more questions

UPDATE:

and inspires me to become a sponsor. I was on the fence for a while, but now, I’m convinced. I’m sure potential members will be flocking to sign up thanks to your invaluable feedback.


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## RDalman (Apr 28, 2021)

Heli said:


> Almost there, you forgot the tempering cycle details. Keep up the good work and should be proud of yourself for providing such great feedback. Really makes me want to post more questions.


Temper at 324 c. 167 secs holding time


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## Heli (Apr 28, 2021)

RDalman said:


> Temper at 324 c. 167 secs holding time


This is testament to your thoroughness, way to go again!


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