Zero tolerance failures???

October 06, 2018, 04:36 PM

I saw a video on YouTube last night about how lots of Zero tolerance knives fail to stay locked open when the spine is tapped on something (in this video, a roll of tape). I found that sort of strange since ZT knives are supposedly rugged and “over built”.

This morning I went to my buddies house who is a huge ZT fan and makes fun of my Emerson’s, well every single one of his ZT knives except one failed this test.

Does anybody here have some ZT knives to try out, horn it and whack the spine onto something like a roll of duct tape and see if it stays open.

To say I was surprised is an understatement; I won’t be spending any $$$ on ZT knives.

October 06, 2018, 06:16 PM

az4783054

That's a pretty broad condemnation of ZERO TOLERANCE knives. Which models did YouTube blast? Which models did your friend have?

I don't carry around a roll of duck tape as a general rule but I did give my 0302 several good raps against a shelf. It stayed locked up solid.

October 06, 2018, 07:57 PM

newmexican

quote:
Originally posted by az4783054:
That's a pretty broad condemnation of ZERO TOLERANCE knives. Which models did YouTube blast? Which models did your friend have?

I don't carry around a roll of duck tape as a general rule but I did give my 0302 several good raps against a shelf. It stayed locked up solid.

If you get on YouTube and just look for zero tolerance failures, there’s a bunch of videos.

I don’t know all the models my friend has but I know one is an 0350.

October 07, 2018, 08:56 AM

ffips

I have used pocket knives for conservatively at least 30+ years. I can't think of a single time in all those uses that I "whacked" the spine for any reason. Sure, I have seen people "batton" through wood. Thing is, if one used the RIGHT tool for the job, there is no reason to whack the spine. My shoe fails as a hammer...

Now, I suppose if one had a double edged locking knife, this sort of test would make a bit more sense. Short of that it looks like abuse to me.

Ymmv.

October 07, 2018, 09:38 AM

madmatt

Damn, and here I was about to gift my 0450, 0900, 0770, and the flawed 0620 to my kids!!!!!!!!!! Nope, not happening!

If anyone out there needs to separate themselves from such blatant failed items as evidenced on YouTube, "I'm your huckleberry!"

October 07, 2018, 10:16 AM

imfrogman

When I ran my truck into a brick wall, it failed miserably. I cannot believe that Chevy advertises it is built like a rock. I wont be spending any $$$ on chevy trucks.

October 07, 2018, 11:34 AM

az4783054

I've since tried my 0350 and it also stayed locked up tight. From my investigation of a very broad accusation, I'd call this supportive test 'fake news'.

But maybe I should have tried it six feet up a ladder at various angles?

October 07, 2018, 10:23 PM

newmexican

Lol

October 07, 2018, 10:54 PM

Lateck

I have complete confidence in my ZT's.
I don't whack the spline of any on my folders, period.

Lateck,

October 07, 2018, 11:53 PM

agony

Although I'm not a big fan of most of the ZT knives, I do have a couple that I have never used or carried. I may dig them out and see if they pass the spine whack test.

Even though most folks would never use their knives in such a manner as to cause a blow to the spine, it is an easy test to perform when investigating the integrity of the lock. And I'm not talking about pounding on the spine with excessive force. Reasonable tapping or whacking the spine should suffice. If anyone knows of a better test, please advise.

Also, using any frame lock knife properly should prohibit the lock from failing with normal use if grasped appropriately.

I've seen some of these videos, and some of the comments lead one to believe that one of the youtubers is a disgruntled ex-employee of KAI.

Then again I've also seen lock failure vids on other brands...CRK, etc.

October 11, 2018, 07:34 PM

agony

Okay, so I pulled out the only two ZT's I have--a 0450 and a 0452, both full titanium models, not the CF scaled versions.
These are essentially new, and I never carried or used them. Probably flipped them open less than 10 times before they were put away.

The smaller 0450 is solid. After several whacks on the spine, the knife stayed open.

The larger 0452 however, will close even with a light whack. I do notice that the frame lock maybe covers 20% of the tang, while the 0450 is about 50%.

My thought is that it is either:
-not enough lock to tang coverage
-wrong lock/tang geometry
-needs broken in
-the titanium slab's cut is too long, causing the lock to disengage too easily.

That said, I put on a slice proof glove and a thick leather glove on top of that, and gripped the knife in such a way that the hand naturally compresses against the lock. Then I whacked the spine while holding the knife in such a manner. It did not fail. I also held it in an icepick grip, and again, no failure after whacking the spine.
Hence I don't think it's a big issue for normal use.

While I was at it, I whacked on a couple other knives in my collection. Some failed, most didn't.
-CRK large regular. No failure.
-CRK small regular. No failure.
-CRK large Classic. No failure.
-BKC AXIS locked knives, various. No failures.
(however I was able to cause a Griptilian and a 710 to fail when I whacked the pommel end on a table).
-Kershaw assisted knives. No failure.
-Ganzo AXIS locked clone of the HK 14205. FAIL.
-However the other Ganzos I have with AXIS did not fail.
-Benchmade Barrage with assist removed; failed.
-Various Spyderco back-locked knives. No failures.
-Spyderco PM2 and Spyderhawk compression lock, no failures.
-A couple cheap Buck/mayo locks. Two of three failed.
-Liner locked BKC Sentinel. No failure.
-Hinderer XM18, no failures.

I got tired and bored after this.

October 11, 2018, 08:34 PM

newmexican

quote:
Originally posted by agony:
Okay, so I pulled out the only two ZT's I have--a 0450 and a 0452, both full titanium models, not the CF scaled versions.
These are essentially new, and I never carried or used them. Probably flipped them open less than 10 times before they were put away.

The smaller 0450 is solid. After several whacks on the spine, the knife stayed open.

The larger 0452 however, will close even with a light whack. I do notice that the frame lock maybe covers 20% of the tang, while the 0450 is about 50%.

My thought is that it is either:
-not enough lock to tang coverage
-wrong lock/tang geometry
-needs broken in
-the titanium slab's cut is too long, causing the lock to disengage too easily.

That said, I put on a slice proof glove and a thick leather glove on top of that, and gripped the knife in such a way that the hand naturally compresses against the lock. Then I whacked the spine while holding the knife in such a manner. It did not fail. I also held it in an icepick grip, and again, no failure after whacking the spine.
Hence I don't think it's a big issue for normal use.

While I was at it, I whacked on a couple other knives in my collection. Some failed, most didn't.
-CRK large regular. No failure.
-CRK small regular. No failure.
-CRK large Classic. No failure.
-BKC AXIS locked knives, various. No failures.
(however I was able to cause a Griptilian and a 710 to fail when I whacked the pommel end on a table).
-Kershaw assisted knives. No failure.
-Ganzo AXIS locked clone of the HK 14205. FAIL.
-However the other Ganzos I have with AXIS did not fail.
-Benchmade Barrage with assist removed; failed.
-Various Spyderco back-locked knives. No failures.
-Spyderco PM2 and Spyderhawk compression lock, no failures.
-A couple cheap Buck/mayo locks. Two of three failed.
-Liner locked BKC Sentinel. No failure.
-Hinderer XM18, no failures.

I got tired and bored after this.

Thanks for running that test, me and my budddy messed around a it more with it and 2 0350s failed as well as 2 others I forget the models.

October 11, 2018, 09:08 PM

agony

quote:
Originally posted by newmexican:

Thanks for running that test, me and my budddy messed around a it more with it and 2 0350s failed as well as 2 others I forget the models.

Yeah it definitely doesn't inspire a lot of confidence in their supposed 'overbuilt' claim.

Next week when I get a chance I'll take apart the 0452 and look closer at the steel insert for the framelock...that's where I suspect the issue lies. I'm betting on less-than-perfect geometry considering the piece may shift when it is finally installed onto the locking bar. I seriously doubt ZT is hand-fitting every single lock insert. In the meantime it really makes me love my axis locked knives so much more.

October 11, 2018, 11:14 PM

newmexican

quote:
Originally posted by agony:
quote:
Originally posted by newmexican:

Thanks for running that test, me and my budddy messed around a it more with it and 2 0350s failed as well as 2 others I forget the models.

Yeah it definitely doesn't inspire a lot of confidence in their supposed 'overbuilt' claim.

Next week when I get a chance I'll take apart the 0452 and look closer at the steel insert for the framelock...that's where I suspect the issue lies. I'm betting on less-than-perfect geometry considering the piece may shift when it is finally installed onto the locking bar. I seriously doubt ZT is hand-fitting every single lock insert. In the meantime it really makes me love my axis locked knives so much more.

Speaking of which, next time you get your ZTs our, can you see if there’s any play in the blades when they are “locked” open, slight clinking etc. some of the videos demonstrate this as well as the knives that I’ve seen fail in person.

October 14, 2018, 05:44 PM

Scurvy

Just get fixed blades if you are that concerned about it.

I have never been a fan of the spine whack test. It's just not a realistic test. The minute your hand goes around the handle to grip the knife, the lockup becomes exponentially more secure.

There is a certain subset of people on the internet who have a weird personal vendetta against ZT. I don't know exactly why but there have been multiple 'questionable' reviews made on youtube with all types of wild accusations. Anything from the heat treat of the steel to the lock up to anything else they can think of.

All it takes is a few twists of the pivot to make a knife look off-center, have blade play and not lock up correctly.

I would suggest that if you are going to watch knife reviews on youtube, you watch credible reviewers who dedicate their channel to it and not random people who may or may not have a bone to pick.

There was a guy on Bladeforums a few years ago who was trashing ZT every way he could because they wouldn't warranty his knife. He showed videos of all of the supposed problems etc and just wouldn't stop trashing them. Finally a rep from the company posted the letter he attached with the warranty form where he had asked them to change the blade out for a different finish and do some other custom work on the knife while it was there. They obviously declined and suddenly the knife became an unusable piece of crap that ZT needed to refund him in full because it was so bad.

October 14, 2018, 06:02 PM

newmexican

quote:
Originally posted by Scurvy:
Just get fixed blades if you are that concerned about it.

I have never been a fan of the spine whack test. It's just not a realistic test. The minute your hand goes around the handle to grip the knife, the lockup becomes exponentially more secure.

There is a certain subset of people on the internet who have a weird personal vendetta against ZT. I don't know exactly why but there have been multiple 'questionable' reviews made on youtube with all types of wild accusations. Anything from the heat treat of the steel to the lock up to anything else they can think of.

All it takes is a few twists of the pivot to make a knife look off-center, have blade play and not lock up correctly.

I would suggest that if you are going to watch knife reviews on youtube, you watch credible reviewers who dedicate their channel to it and not random people who may or may not have a bone to pick.

There was a guy on Bladeforums a few years ago who was trashing ZT every way he could because they wouldn't warranty his knife. He showed videos of all of the supposed problems etc and just wouldn't stop trashing them. Finally a rep from the company posted the letter he attached with the warranty form where he had asked them to change the blade out for a different finish and do some other custom work on the knife while it was there. They obviously declined and suddenly the knife became an unusable piece of crap that ZT needed to refund him in full because it was so bad.

But then again, I’ve seen it first hand as did the guy a few posts up who tested it for himself. I don’t think either of us have any sort of anti ZT agenda. Just because you don’t like it dosent make it fake news.

October 14, 2018, 07:01 PM

Scurvy

quote:
Originally posted by newmexican:

But then again, I’ve seen it first hand as did the guy a few posts up who tested it for himself. I don’t think either of us have any sort of anti ZT agenda. Just because you don’t like it dosent make it fake news.

That's not what I even said. At no point did I even say ZT had perfect locks 100% of the time. I'm just saying minor to non issues can get blown up into major failures by the wrong kind of people. I don't even know who's video you watched so I can't comment on it.

If I can't close the knife with my hands when it's locked open, I'm happy. I think spine whacks are a stupid and useless test personally so none of it bothers me. If it did, I would just have stupid Cold Steel Triad locks which was designed for people who put significant stock into spine whack tests.

October 14, 2018, 08:08 PM

agony

I have no beef with ZT or most knife companies.
However, when 1 of my 2 ZTs have lock failure, which is 50% sample size, then this concerns me enough to not trust their products.

The spine whack test may not be a realistic test but a lock shouldn't fail with a light tap to the spine. It's that simple.

For SD I usually carry a fixed blade when possible. If dress code deems it difficult, then a balisong as it is the sturdiest most bombproof locking system of any folder design to date. Any other knife I carry is just jewelry. But said jewelry needs to be completely reliable.

October 17, 2018, 01:30 PM

cslinger

I have several ZT knives that I generally like. However, that being said, I did test them out and the results are as follows.

0700 - Stayed locked up.
0700(black blade) - Stayed locked up.
0350(black blade)- Stayed locked up
0770CF - Stayed locked open

Here is where things fall apart.

0200 - overcomes the lock fairly easily. This is by far the biggest heaviest blade and seems to be "under locked/sprung" if you will. Now it doesn't overcome when holding and handling the knife as normal but any minor spine whack will overcome the lock otherwise and that is disappointing.

I don't generally use/carry huge knives (which I consider the 0200 to be, at least as far as a folder is concerned and I feel its blade size/weight has something to do with it.

At any rate, thought I would add a data point.

I have been carrying and been on a bit of a Spyderco kick as of late.

I did try this test with pretty much all my Spyderco's, Benchmade's and a hand full of one off's from other brands and didn't see any failures but the VAST majority are 3.5ish blades or smaller and range in locks from Axis, compression, back lock and liner locks.