Spyderco Forums

Thought some of you would enjoy seeing this...

Kase' Knives did a regrind and re heat treat on his Slysz Bowie. If you're not familiar with Roman of Kase' Knives he's a young talented knife maker and heat treating wizard that lives in Switzerland. Although just out of school, Bohler Uddeholm has already worked with him on the HT for Vancron SC and other future knife steels.

This CTS-XHP has been triple tempered, triple cryo'd, and has an HRC of 64.5

D@mn that's cool. Thanks for sharing, Turbo.

That is sick.

Awesome

Very nice work; very impressive!

Really interesting! Thanks for the share

Nice!

Thank you so much for these kind words bbturbodad! After years of collecting knives and browsing this forum amongst others as a hobby before I became a maker a year ago, it still feels totally UNREAL to find my own name here... Thank you to all who support my work both by buying my knives as well as giving me this kind of support!! You guys are the reason I am able to do what I do: making a living off making knives.
I am not sure if I am allowed to post my website here, but if you want to know more about my work, my website is linked in the description of the Youtube video in the OP's post.

Thats awesome and cant of been cheap - was there a problem with the factory grind etc or was it just because you can?!

The edge would chip or roll on cutting open plastic packaging, no matter how often I resharpened it. UCI testing then revealed overheated steel in the lower blade area from the factory grinding - as with so many knives. Usually it is not that bad with Spyderco though that a few sharpenings could not fix it. (Reason I like Spyderco so much.) In addition, there was a ton of burr formation during sharpening. So what to do - re heat treat!


Also, somebody asked under the youtube video above:
"What does tripple tempering and cryo do to the steel?"
I thought that this is an excellent question and maybe you guys also are interested to know, so below you will find my answer:

I am glad you ask! But be warned, your question leads to a huuuuuge rabbit hole. If you want to know the details, follow the link at the end of this comment. What follows is a (very!!) brief summary partially based on the link below.
Here we go:
Cryo drastically reduces and in some cases completely eliminates retained austenite which will remain especially in stainless steels after quench to various degrees. Retained austenite is unwanted for several reasons - mainly because it lowers edge retention and leads to excessive burr formation during sharpening. Therefore, a first cryo after quench is done because it reduces the retained austenite (the article linked below explains the mechanisms behind this process in detail) and it is by far the most important cryo.
Now, why several temperings and also another cryo inbetween each of those several temperings? Super short answer: Because the retained austenite transformation is more complete that way.
More detailed answer:
One must first understand why we temper: Basically, after quench, we (hopefully!) have a lot of martensite. This martensite is brittle however. Without going into details on how it works, the tempering removes this brittleness.
However, despite the initial cryo after quench, in addition to the martensite we also must expect to be some retained austenite still present in the steel. This retained austenite will, if tempering temperatures are high enough (their height depends on the steel, but generally true for the so called "secondary hardening range" for high alloyed steels) transform this retained austenite into martensite. This martensite - again, just like after quench- is brittle, so this is why we should add at least one other temper after the first temper in order to "take out the brittleness" of this newly "born" martensite. And studies give hints for a third temper being beneficial. (Therefore I do it.) However, during tempering, and especially low tempering like it was done on this CTS-XHP steel blade, the carbon in the steel can "wander" (diffuse) back into this retained austenite we actually want to eliminate and stabilize it instead - "stabilizing" meaning in this context that cooling to room temperature in order to get rid of it like it is often done after the first tempering will not transform it to martensite. This is where and why the additional cryos come into play: By going to - 196°Celsius, we can eliminate or at least reduce even that stabilized austenite.
Allright, I hope I could give some insights and maybe answer your questions - here is the afformentioned link:
https://knifesteelnerds.com/2018/12/10/ ... el-part-2/

What's wrong with this guy ...he ruined that awesome blade :rolleyes:

elena86 wrote: ↑

Tue Dec 17, 2019 11:36 am

What's wrong with this guy ...he ruined that awesome blade :rolleyes:

??? Is this an attempt at sarcasm, or... care to elaborate?

It is probably sarcasm - and if not, I think it is only a matter of time until he or she will realize that there is much more to heat treat than they thought.
Also, somehow all my posts need to undergo approval by admins which takes over a day each time - any idea what I can do about this? Because I'd love to answer some of the questions here...

It visually looks the same. What was the point?

I was expecting something more noticeable like the reground Nirvana.

BigGrove wrote: ↑

Tue Dec 17, 2019 3:29 pm

It visually looks the same. What was the point?

I was expecting something more noticeable like the reground Nirvana.

It has a very detailed custom HT and is stronger and more stable now.

He does some incredible work and at his age to be putting out the quality of info & work he's done is mind blowing. The work he has done on Vancron Superclean has been amazing so far. People like him, TripleB, and others like them are really are the forefront of this new wave of the blade world and we should all thank them for their many many many hours invested with no real incentive other than the love of it.

bbturbodad wrote: ↑

Mon Dec 16, 2019 2:43 pm

Thought some of you would enjoy seeing this...

Kase' Knives did a regrind and re heat treat on his Slysz Bowie. If you're not familiar with Roman of Kase' Knives he's a young talented knife maker and heat treating wizard that lives in Switzerland. Although just out of school, Bohler Uddeholm has already worked with him on the HT for Vancron SC and other future knife steels.

This CTS-XHP has been triple tempered, triple cryo'd, and has an HRC of 64.5

Looks awesome! Couple of curiosity questions. What is the new spine thickness? What angle is the primary bevel ground to? What thickness is BTE?

Thanks

Mm1313 wrote: ↑

Tue Dec 17, 2019 8:08 pm

He does some incredible work and at his age to be putting out the quality of info & work he's done is mind blowing. The work he has done on Vancron Superclean has been amazing so far. People like him, TripleB, and others like them are really are the forefront of this new wave of the blade world and we should all thank them for their many many many hours invested with no real incentive other than the love of it.

Thank you very much! I try my best. I don't know when my answer will be unlocked by the mods, so I hope it is not too out of context once you can see it.

Deadboxhero wrote: ↑

Tue Dec 17, 2019 5:03 pm

BigGrove wrote: ↑

Tue Dec 17, 2019 3:29 pm

It visually looks the same. What was the point?

I was expecting something more noticeable like the reground Nirvana.

It has a very detailed custom HT and is stronger and more stable now.

This is an honest question... What is that statement based on? Was testing done before and after?

BigGrove wrote: ↑

Thu Dec 19, 2019 8:25 am

Deadboxhero wrote: ↑

Tue Dec 17, 2019 5:03 pm

BigGrove wrote: ↑

Tue Dec 17, 2019 3:29 pm

It visually looks the same. What was the point?

I was expecting something more noticeable like the reground Nirvana.

It has a very detailed custom HT and is stronger and more stable now.

This is an honest question... What is that statement based on? Was testing done before and after?

As I wrote above, I did it because the edge would constantly fold on cutting open stuff like simple plastic packaging and burr like crazy during the (subsequently very common) resharpenings. That all is fixed now thanks to the re heat treat. Usually, Spydercos ht is decent to good for production in this regard in my experience; especially their ZDP-189, which to my knowledge gets sub zero treatment due to the ht being done only in ht facilities approved by Hitachi. But I am getting off topic. This particular Spyderco underperformed so much despite me sharpening the bevel back and is also my all time favourite so that I decided to do what I did here.
Custom ht can do stuff like this: (please forgive the video quality on this one and jump to the middle after start if you want to see just the results) : https://youtu.be/Z-2861dtYus