Re-Heating Your CRK

[Huntsman Knife Co. LLC.]

Every knife needs to be sharpened but a high wear resistance steel with good edge stability can be maintained for a very long time through stropping and touch ups on ceramic or sand paper.

Hard, high wear resistance steels go longer between sharpenings and have a longer life span than softer steels. Again I almost never sharpen my knives and they see alot of use.

Solid edge geomety, carbide content, hardness and a light strop every few days will keep a knife cutting for a very long time.


The point here is if CR rankle S35VN a point harder people would end up with a knife with much more stable edge geometry that will not only cut better and stay sharper longer but would reduce the need for total resharpenings and contribute to a longer lasting knife. No one wants a blade with 2 millimeters of steel removed from it.

 

[13aphomet]

I'll be getting my first CRK tomorrow (a seb 21) in s35vn. You guys got me all nervous.. hahah

But seriously, I'm gonna use it, and see if the edge retention works for me. If it doesn't, I'll either explore the HT option or sell it. I love perfect fit and finish as much as the next guy but if something doesn't "work" in it's intended role (I need something that lasts all day, I cut alot), then it's gotta go...

This will also be my first experience with S35vn. I've pretty much been a Strider/Spyderco guy. And from reading this thread, the info I gather is "Hi, you just bought a Sebenza, your edge will not last as long as your other knives. Enjoy!"... which sucks..

So yah, I hope you guys are wrong and it works out. The Sebenza has been calling my name for awhile and I'm excited about it.

 

[CrimsonTideShooter]

Ah I see, that is what I would call a two tone finish rather than "unfinished" and that actually takes more work as the 600 satin is done by hand. Some people don't like the two tone finish some do, I personally don't. As for the heat treat that is and has been part of CRKs design philosophy from the start. I can get a workable edge on my Sebenza or Umnumzaan using anything from the edge of a car window to a rock and lots of things inbetween. That was the point, a knife that is easy to maintain regardless of where one finds them selves. Best of luck to any one trying that with S90V at +60 Rc. It seems to me many have been spoilt with these super steels that are the norm now and have also grown used to being able to sit at home and sharpen them comfortably with good diamond and ceramic stones....

While I see what you're saying, the S90V example isn't the best.

S90V at 58 will still be MUCH harder to sharpen than S35VN at 62 - just due to the composition alone. Much of the "difficulty" in sharpening comes from the composition, not the hardness. Yes, hardness does play a role - but Chris could run the S35 up to 60-61 without there being much of a change in sharpening ability. I know this because I've sharpened S35 at 60. The composition makes it a dream to sharpen compared to a lot of steels.

 

[marthinus]

Every knife needs to be sharpened but a high wear resistance steel with good edge stability can be maintained for a very long time through stropping and touch ups on ceramic or sand paper.

Hard, high wear resistance steels go longer between sharpenings and have a longer life span than softer steels. Again I almost never sharpen my knives and they see alot of use.

Solid edge geomety, carbide content, hardness and a light strop every few days will keep a knife cutting for a very long time.


The point here is if CR rankle S35VN a point harder people would end up with a knife with much more stable edge geometry that will not only cut better and stay sharper longer but would reduce the need for total resharpenings and contribute to a longer lasting knife. No one wants a blade with 2 millimeters of steel removed from it.

In my opinion, this is user specific and what is expected from the knives in user use. Unfortunately one will get to a point, or low enough angle, where the high wear carbides (usually vanadium) can start working against you and you end up with carbide tear out with lateral stress to the edge.

This is of course when you are pushing your knife to very extremes even if they are CPM grade and a simple microbevel can decrease the carbide tear out.

Everything in steel is a give or take. You sacrifice one thing for another and a balanced steel between strength, toughness, edge retention (wear resistance), edge stability, corrosion resistance and price. Pick three (or two), you cant have them all (cant remember the correct saying I heard). An excellent balanced steel I feel is RWL-34 or CPM-154 giving you a balance between all these characteristics.

Example of the affects of N in an alloy can be read in this patent document, page 3 line 5, but as one can see it might not be enough for intended application and additional alloys are required.

http://www.freepatentsonline.com/EP1052300.pdf

IMO it is up to the knife maker to chose from available data what will work best in the design concept, use, and application while still keeping warranty work to a minimum such as broken tips etc. These factors influence the HRC as well. Especially in production knives.

 

[Haze]

I think you misunderstand my point, or perhaps I misunderstand yours ? It seeme to me we are saying the same thing.
I have much time behind me working with knives and other cutting tools as well as much experience trough my interest in knives and the out doors in general. I am happy in my assessment but the wants or needs of one person will often be different from the next so there is clearly no absolute right or wrong.
I will ask that you don't try and lecture me with your pseudo-metallugist/scientific chatter though. I actually did metallurgy as part of my degree so I feel that I understand the chemistry of what is going on quite well.

While I see what you're saying, the S90V example isn't the best.

S90V at 58 will still be MUCH harder to sharpen than S35VN at 62 - just due to the composition alone. Much of the "difficulty" in sharpening comes from the composition, not the hardness. Yes, hardness does play a role - but Chris could run the S35 up to 60-61 without there being much of a change in sharpening ability. I know this because I've sharpened S35 at 60. The composition makes it a dream to sharpen compared to a lot of steels.

 

[TTTis]

I'll be getting my first CRK tomorrow (a seb 21) in s35vn. You guys got me all nervous.. hahah

But seriously, I'm gonna use it, and see if the edge retention works for me. If it doesn't, I'll either explore the HT option or sell it. I love perfect fit and finish as much as the next guy but if something doesn't "work" in it's intended role (I need something that lasts all day, I cut alot), then it's gotta go...

This will also be my first experience with S35vn. I've pretty much been a Strider/Spyderco guy. And from reading this thread, the info I gather is "Hi, you just bought a Sebenza, your edge will not last as long as your other knives. Enjoy!"... which sucks..

So yah, I hope you guys are wrong and it works out. The Sebenza has been calling my name for awhile and I'm excited about it.

Well Ankerson (I believe) had an umnumzaan tested at 59.5 from the factory (S30 though). So you may get lucky. I'd say mine have probably been on the lower end of the spectrum around 58... maybe lower. Wouldn't last a full days work without hitting the stone... stropping couldn't bring it back. Just use it for a day and see. If it is really bad, send it to Farner and you'll see a big difference. In my case from the factory, they would dull about twice as quick as my VG10 Delica. But with anything YMMV.

 

[CrimsonTideShooter]

I think you misunderstand my point, or perhaps I misunderstand yours ? It seeme to me we are saying the same thing.
I have much time behind me working with knives and other cutting tools as well as much experience trough my interest in knives and the out doors in general. I am happy in my assessment but the wants or needs of one person will often be different from the next so there is clearly no absolute right or wrong.
I will ask that you don't try and lecture me with your pseudo-metallugist/scientific chatter though. I actually did metallurgy as part of my degree so I feel that I understand the chemistry of what is going on quite well.

It's most likely that I misunderstood, and I wasn't trying to lecture you at all. I've had just about zero formal education on metallurgy. I do however have a masters from bladeforums uni though.

 

[marthinus]

Well Ankerson (I believe) had an umnumzaan tested at 59.5 from the factory (S30 though). So you may get lucky. I'd say mine have probably been on the lower end of the spectrum around 58... maybe lower. Wouldn't last a full days work without hitting the stone... stropping couldn't bring it back. Just use it for a day and see. If it is really bad, send it to Farner and you'll see a big difference. In my case from the factory, they would dull about twice as quick as my VG10 Delica. But with anything YMMV.

Just curious, but how long did you use your knife for and how mach metal did you remove? Wondering because I have found that some knives come with a slightly burnt edge and only get to experience the real HT after some significant metal has been removed, up to 1mm on some knives.

 

[russianpolander]

Mine must be a good one then. I have had no trouble with it. View attachment 298320

 

[Haze]

Aye, there's a few of you guys about. :thumbup:

It's most likely that I misunderstood, and I wasn't trying to lecture you at all. I've had just about zero formal education on metallurgy. I do however have a masters from bladeforums uni though.

 

[13aphomet]

Well Ankerson (I believe) had an umnumzaan tested at 59.5 from the factory (S30 though). So you may get lucky. I'd say mine have probably been on the lower end of the spectrum around 58... maybe lower. Wouldn't last a full days work without hitting the stone... stropping couldn't bring it back. Just use it for a day and see. If it is really bad, send it to Farner and you'll see a big difference. In my case from the factory, they would dull about twice as quick as my VG10 Delica. But with anything YMMV.

I'll def have to see for myself.. Dulls twice as fast as a Delica? Goddamn.. If that's the case it would very very disappointing. I'd like to see Crimson do one of his tests side by side with a Delica actually.. kinda like them tests Smokeeater's been doin.. Whaddya say man??

 

[dflores]

To be honest i'd rather have a CRK with CPM-154 over s30 or s35. Just my $0.02!

 

[Huntsman Knife Co. LLC.]

I would too. CPM 154 is a great all arounder and is a breeze to sharpen and tool.

 

[TTTis]

Just curious, but how long did you use your knife for and how mach metal did you remove? Wondering because I have found that some knives come with a slightly burnt edge and only get to experience the real HT after some significant metal has been removed, up to 1mm on some knives.

That was my first thought, however I've never seen a factory edge dent inward like my CRK's. Used and removed enough to know the factory HT was too soft (for me). Had plenty of knives with a bunk factory edge that got better after a few sharpening's... not the case here.

 

[13aphomet]

That was my first thought, however I've never seen a factory edge dent inward like my CRK's. Used and removed enough to know the factory HT was too soft (for me). Had plenty of knives with a bunk factory edge that got better after a few sharpening's... not the case here.

So did you re-heat treat yours? If so, tell me about your experience..
I'd like to know more about this process if anyone wants to chime in.

 

[TTTis]

So did you re-heat treat yours? If so, tell me about your experience..
I'd like to know more about this process if anyone wants to chime in.

Read the whole thread? My experiences are littered throughout. Check the beginning of this thread.

As far as the process.... take your stud out, fill out the info sheet (PB HT Page) and send the blade in. I just write down I want 60 rockwell as Paul said that is the highest he personally can take S30/S35 with his equipment. That is pretty much it. Turnaround is usually about a full week or so. I've sent two Seb blades in at different times. Both went in on a Monday, had them both back the following Monday. Great guy to work with. If you are unsure about anything just call him up, he is very down to earth and loves talking about his craft.

Oh and one other thing. I know a few people asked me about warping in PM's. I haven't had an issue with that. Paul was telling me that finished blades (even thin) that are straight can be re-treated just fine without warping. If the blade is warped after finishing it will just make it worse re-treating it. Steel has a sort of memory, if already finished straight re-heating won't be a problem. I've never seen a warped Seb blade from the factory so you should be just fine. Mine all came back exactly the same as they left, just with a slight cast over the blade.

 

[13aphomet]

Read the whole thread? My experiences are littered throughout. Check the beginning of this thread.

Sorry, I read the thread too quickly a few days ago.. Thanks for your response though man. I'll keep it in mind. So far, I've only used my Seb lightly and it's seemed to do okay. No rolling or squashing. I'm always using a knife at work and I gotta use it pretty hard so when I started carrying the Sebenza I also took my StriderSMF 3v as a backup for the hard stuff. I mean, last week I was prying nails out of super thick cardboard tubes of 10ft banner material. The 3v did fine, I really love it. So I basically just used the Seb for cutting pieces of tape and such.

I'll keep the HT in mind, but honestly it just seems like stock seb, or the HT seb prolly isn't right for a work knife for me. (I don't usually pry, I only did that cause it's Strider 3v) I do work a knife hard though, and I feel if I used it for everything the stock seb would dull too quick, and the HT seb might chip.. I dunno, guess I have to try. I really like Striders s30v, hasn't chipped on me, but it's also a much thicker edge..

 

[DanG]

Quite interesting that some re-ht their Sebenza blades to suit their individual needs. Always a sign that the individual has mastered his tasks and tools. Would like to ask two questions to SMI or anyone else that had this done:

First, CRK S30V is "famous" for a raised burr/rolling edge that is tedious to knock off. I suspect this is eliminated with the re-ht?!

Second, the issue with the lower CRK ht as I remember is not so much ease of maintenance/sharpening as someone wrote in this thread but first and foremost preventing chipping. That's the original reason for dropping a few degrees RW when the steel was developed in cooperation with Chris Reeve. Thus, are there chipping problems after re-ht?!

 

[wolf5391]

Quite interesting that some re-ht their Sebenza blades to suit their individual needs. Always a sign that the individual has mastered his tasks and tools. Would like to ask two questions to SMI or anyone else that had this done:

First, CRK S30V is "famous" for a raised burr/rolling edge that is tedious to knock off. I suspect this is eliminated with the re-ht?!

Second, the issue with the lower CRK ht as I remember is not so much ease of maintenance/sharpening as someone wrote in this thread but first and foremost preventing chipping. That's the original reason for dropping a few degrees RW when the steel was developed in cooperation with Chris Reeve. Thus, are there chipping problems after re-ht?!

I think the re-HT is mainly for the s35vn blades that are designed to be at higher rockwells with out chipping. I think that if you ward to take the older s30v blades and re-HT them higher Rc then they would chip out.

I could be wrong, But I know Chris used s35vn so it could be HT harder without chipping out, but then he kept the rockwell the same as before which is counter productive IMO.

 

[TTTis]

Sorry, I read the thread too quickly a few days ago.. Thanks for your response though man. I'll keep it in mind. So far, I've only used my Seb lightly and it's seemed to do okay. No rolling or squashing. I'm always using a knife at work and I gotta use it pretty hard so when I started carrying the Sebenza I also took my StriderSMF 3v as a backup for the hard stuff. I mean, last week I was prying nails out of super thick cardboard tubes of 10ft banner material. The 3v did fine, I really love it. So I basically just used the Seb for cutting pieces of tape and such.

I'll keep the HT in mind, but honestly it just seems like stock seb, or the HT seb prolly isn't right for a work knife for me. (I don't usually pry, I only did that cause it's Strider 3v) I do work a knife hard though, and I feel if I used it for everything the stock seb would dull too quick, and the HT seb might chip.. I dunno, guess I have to try. I really like Striders s30v, hasn't chipped on me, but it's also a much thicker edge..

No problem, just thought I'd point that out if you hadn't read it yet. I wouldn't be doing too much prying with the Seb blade at any hardness frankly. Probably a good thing to bring the SMF. I pry small staples out, but that is really the limit for my Sebs. I usually have one of those small pico pry bars for that anyways. I use the tip of the knife a lot for cutting so I'd be pretty pissed if that broke off.

I'm certainly not easy on my two Sebs, but I have yet to have issues with chipping on the hardened blades. As long as it isn't slamming into pieces of metal or the like... you should be fine. I've cut up cardboard, hard and soft wood, zip ties, some aluminum cans and all the regular edc stuff (tape, packages, etc). No chipping yet and no denting. I definitely wouldn't shy away from using your Seb.

Quite interesting that some re-ht their Sebenza blades to suit their individual needs. Always a sign that the individual has mastered his tasks and tools. Would like to ask two questions to SMI or anyone else that had this done:

First, CRK S30V is "famous" for a raised burr/rolling edge that is tedious to knock off. I suspect this is eliminated with the re-ht?!

Second, the issue with the lower CRK ht as I remember is not so much ease of maintenance/sharpening as someone wrote in this thread but first and foremost preventing chipping. That's the original reason for dropping a few degrees RW when the steel was developed in cooperation with Chris Reeve. Thus, are there chipping problems after re-ht?!

Whether S30 or S35, I wasn't a fan of sharpening the stock HT. I had the same experience as you while sharpening. Both my S30 and S35 blades are hardened to 60. The stock S30 dulled super fast compared to other S30 I had in the past. That is the main reason I had that one hardened too. I did have some pretty bad rolling and fast dulling, but no inward denting like the stock S35.

At 60, both my S35 and S30 blades haven't chipped at all. I actually find the harder blades easier to sharpen as well since I'm not having to battle the burr (plus not having to do it daily is nice lol). I now use the S35 much more since it's a CF variant and super light. The S30 was carried daily for about five months before the CF came into play (now carried daily). If I bought another S30 Seb I wouldn't hesitate to get it hardened as well.