ATTENTION SAL GLESSER tuff in for warranty, won't catra?

[dmiddleton]

hello, i'm here as a concerned customer. i am one who tests and uses different steels and knives from different brands for my own research as far as edge retention and other behavior can be noted. i purchased a spyderco tuff two years ago and used it for testing edge retention and i found that it was a very good performer right out of the box, unfortunately, it had an issue with the lock and so i sent it in for repair and what i received in replacement was another spyderco tuff with horrible edge retention by comparison as i test retention with hundreds of runs on cardboard which is produced by the same factory, is rated to hold the same weight, etc... and i can tell beyond a shadow of a doubt that there is a problem with this replacements edge retention as it was that poor from day one which was around a year ago. i decided to continue using this knife as my every day carry and to continue to sharpen it in hopes that the issue was due to overbuffing during sharpening, it seems that a year later, i have not seen improvement. by the advice of cliff stamp i have sent it in to be catra tested and rockwell tested. i have done so and have been told that the catra test is not necessary as it had passed the rockwell test. in speaking with mr. stamp whom i highly admire for his knowledge and expertise, he has advised that i contact spyderco yet once again in hopes that mr glesser might take notice of the issue i have stated as a rockwell test is only meant to find one particular type of problem and that there may be a number of issues that may be present that could be being overlooked. i was told by customer service over the phone before i sent it in and today that the edge bevel is wide but, this issue i am having has nothing to do with binding during cutting, it has to do with how long the apex will cut the materials i am testing with and how after hundreds of runs, the problem is still the same. this is my second sample in this steel and the results are FAR lower than the performance i had with the first sample that was replaced by spyderco for the issue with the lock. i would have rather had the faulty lock than the poor edge retention i am having now as at least i am aware of the likelihood of lock failure and can operate accordingly. attention to this matter would greatly be appreciated and in no way do i mean to show disrespect to anyone as i value spyderco and their working tools performance as they are at the top tier of performance.

[dmiddleton]

also on a side note, i had convex ground the blade by hand with sharpening stones, not a belt sander or grinder and blended the shoulder between the primary and secondary bevels to circumvent the issue with binding and as i said my issue was not with binding but with constant burr formation during sharpening since i received the knife and it's poor edge retention. thank you.

[Studey]

Did you convex it on a belt sander? It's easy to burn the temper out of a blade with one.

I don't know that you're going to get very far, given that you've modified the blade, it's much harder to isolate if there was an issue from the factory or if it's from the modifications after.

I'm not saying that you screwed up your knife, just that Spyderco now has no good way of knowing where the problem originated.

[dmiddleton]

no, i convexed it by hand on stones.

[shunsui]

There is the possibility your first blade was the greatest Tuff blade of all time and no other Tuff blade will ever equal it.

[dmiddleton]

that had occurred to me but, assumption will not determine whether that is the issue.

[razorsharp]

Dan,

My biggest recommendation would be to seen it in . If you have proof that it doesn't perform up to snuff compared to your old one I am sure they would replace it. Spyderco is based on performance with a GREAT warranty , I am sure they would have no trouble replacing a blade that doesn't perform.

[The Deacon]

Dan,

My biggest recommendation would be to seen it in . If you have proof that it doesn't perform up to snuff compared to your old one I am sure they would replace it. Spyderco is based on performance with a GREAT warranty , I am sure they would have no trouble replacing a blade that doesn't perform.

Sounds like he already sent it in, Spyderco Rockwell tested it, and felt it was within specs. He'd like it to be CATRA tested as well, Spyderco feels that is unnecessary, and he disagrees. Unlike Rockwell testing, that is quick and costs next to nothing once you have the equipment, the media used for, and destroyed by, CATRA testing does cost something and the test takes longer, so I can see why Spyderco may not want to set a precedent for everyone who thinks their blade should hold an edge longer.

[sal]

Hi Dan,

Welcome to our forum.

I would suggest you send it in and call it to my attention. I will alert Customer Serivice and R&D that it's coming in.

sal

[wrdwrght]

He'd like it to be CATRA tested as well, Spyderco feels that is unnecessary, and he disagrees. Unlike Rockwell testing, that is quick and costs next to nothing once you have the equipment, the media used for, and destroyed by, CATRA testing does cost something and the test takes longer, so I can see why Spyderco may not want to set a precedent for everyone who thinks their blade should hold an edge longer.

Just so. I thought the point of CATRA was to gain confidence in a production run through random samples. Presumably the batch including Dan's Tuff was CATRA tested and received the green light needed to leave the factory.

[sal]

Charlynn said we have the knife here, so we'll run it through testing.

sal

[dmiddleton]

travis, good to hear from you. it is actually in warranty now. looks like they may test it after all. i hope the one guy who commented that my first one may have been the most awesome spyderco tuff ever and that this one may perform as it's meant to, which is why i was hesitant to report it or send it in. i just figured they would find it to be typical behaviour and that i would have inflamed the tempers of spyderco employees for nothing.

[dbcad]

I have no doubt Spyderco will get to the reason for the discrepancy between the first and second model received. Look forward to hearing the determinations when they arrive.

Charlie

[The Mastiff]

I thought he stated the problem was burring?

as i said my issue was not with binding but with constant burr formation during sharpening since i received the knife and it's poor edge retention. thank you.

Those CATRA cards come from one source and cost money. You start running CATRA tests on every knife and expect to pay a lot more money for knives. :)

If this knife rockwells in spec what has anyone learned? Unless both knives are present there is no way to decide what causes the performance difference. A simple change in geometry will cause a larger difference in performance than a point or two of hardness.

To bugger up a knife, claim a performance loss over an older knife and expect a new one would seem like a.......

Never mind. Too many ways to get in trouble.

I would like to see what his tests are, what his results have been but more so I'd be curious what he does to keep the tests scientific. Perhaps we could learn something here compared to people who publish their results and have them available for comparison.

[Blerv]

Awesome that Spyderco is taking extra care of this concern. Shows what a great company they are. Not going to even get into the request as it's not my place either :).

For me, I would just pick a knife that's more adept at cutting cardboard. A ZDP-189 Endura would blow the Tuff out of the water let alone something like a Manix2 110v based on philosophy of design and carbide content. Regrind one of those and oh boy :D.

[Laethageal]

I thought he stated the problem was burring?

as i said my issue was not with binding but with constant burr formation during sharpening since i received the knife and it's poor edge retention. thank you.

Those CATRA cards come from one source and cost money. You start running CATRA tests on every knife and expect to pay a lot more money for knives. :)

If this knife rockwells in spec what has anyone learned? Unless both knives are present there is no way to decide what causes the performance difference. A simple change in geometry will cause a larger difference in performance than a point or two of hardness.

To bugger up a knife, claim a performance loss over an older knife and expect a new one would seem like a.......

Never mind. Too many ways to get in trouble.

I would like to see what his tests are, what his results have been but more so I'd be curious what he does to keep the tests scientific. Perhaps we could learn something here compared to people who publish their results and have them available for comparison.

Well as you said, knowing more about his test and how they are performed, what are the results and how biais is kept at the lowest he can would help enlighten us about it all.

On the other hand, it seemed clear to me he tried keeping the test the same over and over using the same supplier of cardboard, using same strength cardboard too alone the different testing. Now is there some data about the first tuff thickness behind the edge and the second one? That's something can play a huge role in edge retention vs cardboard. Just look at the manix S110v factory edge and regrind that Jim did. If I remember right, it went from 700 rope cuts with 0.15 behind the edge thickness to something like 1120 cutswhen reground to 0.05 behind the edge. All factory edge aren't the same thickness, there's a slight variation due to human factor.

One way or the other, it seems Sal already has the knife. With some luck, he'll find out what's going on and tell us :)

[Cliff Stamp]

If I remember right, it went from 700 rope cuts with 0.15 behind the edge thickness to something like 1120 cutswhen reground to 0.05 behind the edge.

That isn't a significant difference, and by that I mean it doesn't indicate the edge retention actually increased. Edge retention is not linear and after the initial phase the rate of change slows dramatically. If you are cutting on a scale and determining the stopping point by the measurement on the scale then your precision is extremely low and by that I mean it is 500-1000 cuts which means that number of cuts can be done and the scale won't change by more than +/- 1 lbs and it changes by more than that during the cut itself.


As an aside, if you reduce the edge thickness and cut rope on a scale until some measure of force is increased then of course the number of cuts can increase but that isn't because the edge retention increased it is because the cutting ability is increased. I have knives made out of very basic steels which can cut 3/8" hemp with about 5-6 lbs on a 2" slice. It would take a tremendous amount of number of cuts before the force was 15-20 lbs because it is so low to start but this doesn't mean they have high edge retention as again that is measuring the cutting ability.

[Cliff Stamp]

Well as you said, knowing more about his test and how they are performed, what are the results and how biais is kept at the lowest he can would help enlighten us about it all.

He has a number of videos on YT where he has done trials of various level of rigor. The differences he is claiming are very large so much so they are obvious to him in use. Now I do agree that in all cases justification is an excellent thing to demand, however if the only time people demand justification is when someone makes a complaint and it is ignored when someone makes a post which is praise - well then that is a far worse bias than even the sloppiest of edge retention trials.

[Laethageal]

I am not award of the video he did, simply about the post itself. That's the reason I say some more information might prove useful. In no way am I asking for justification because he claim the knife isn't on par with the other he had, but to know more about his experimentations. I can tell which one of my SB and ZDP hold and edge the longest without a doubt simply from daily usage. Someone trying to keep the same configuration like he says he's doing must be able to say if the knife doesn't perform as the other he had and I'm not going against what he says.

I don't want to hijack your thread, but here's a clarification about how I rate edge holding:

Cliff, I do understand what you're saying about cutting ability versus edge holding, but being that I'm not deeply yet into serious testing knives I usually consider the real edge holding of my knife as of how long it keeps an edge at the lowest angle it can sustain without breaking/deforming during my daily use. I always thin my new knife and use them until I find the lowest bevel angle it can support. From that point I compare my knives, each one at their optimal edge thickness for my use. If, let's say ZDP, could stand 0.08 behind the edge and not chip during my daily use, but that 0.07 kept breaking, then I use 0.08 and close to 10 degree as my reference for ZDP. After a few weeks I estimate how long the edge stayed sharp vs the time I used it. Then if my SB (which presently is about 0.03/0.035 at 1mm from the edge) stay sharp longer because it can simply hold a thinner grind, well just too bad. I name it edge holding and SB wins. I know it ain't as exact as it could be, and that at the same thickness and angle my ZDP was staying sharper for a longer time. It just couldn't handle that thin grind :)

[dmiddleton]

i would prefer to remain anonymous on this matter as well as my testing as i've dealt with forums before and do not welcome people to come and criticize my every statement and my findings. this is one reason why i don't frequent forums. if any further interactions are required, please feel free to contact me by private messaging. it is very possible that the knife i had before was a fluke as far as edge retention is concerned as i have spoken with several people and their conclusion seems to differ from my findings but, there is also the likeliness that their opinion is just parroted from someone they'd heard it from and some dogpile effect may have occurred at some point. thank you for your understanding and please believe i am not trying to embarass spydeco or any of the employees, i feel bad to have had to send the knife in in the first place.