Zero Tolerance Liner Lock Closures?

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BigKurtHaze said:
Really? Maybe not people that drop a couple hunnert bucks on a pocket knife, but John Q. Public types? I'm pretty sure there are literally billions of people that don't know those terms. Literally.
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Batonning and spine whacks are literally the only thing that millions of YouTube watching people know about knives.
Just do a search for spine whack and batonning videos...your life will end before you can watch all of them.

And since YouTube has somehow become the main avenue of knowledge for many people it seems, well, there you go. ;)
 
stabman said:
Batonning and spine whacks are literally the only thing that millions of YouTube watching people know about knives.
Just do a search for spine whack and batonning videos...your life will end before you can watch all of them.

And since YouTube has somehow become the main avenue of knowledge for many people it seems, well, there you go. ;)
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I find it hilarious that two very popular YT knife reviewers recently did videos complaining about how they didn't like the comfort level of a particular slip joint knife when applying a lot of pressure with their thumb on the spine of the blade when cutting... a slipjoint...

I think we give these YT channels way to much credit on their personal opinions.
 
Of course nonknife people aren't going to have the slightest idea what lock rock, or spine whacking is. I could ask random people around me that and none would know. Why would they? They have no interest in knives. I can't even get them to even look at one of mine. I pull out my impressive ultra new expensive blade and say check it out! They glance quickly at the odd (to them) object in my hand, just as quickly look away and go on telling me about some other monotonous event in their life.
 
I think the biggest issue, for me, is a two-part compounded one: how easily the lock was defeated on my personal knives and how many knives are coming back from KAI not fixed.

I really don't want to come across as beating up on ZT. I've purchased 9 of their knives. I have kept 8 of them and gave my 450 to my little brother as a thank you for detailing my car. He loves it. I'm not planning on dumping the others. I probably won't carry the ones that folded as much, but the 3 that held up to 3 or 4 taps are fine in my book.

I guess I'm just confused as to why these premium knives are failing very light stress tests. Why a 70 dollar US made Kershaw made 10 years ago lock does not slip after a very minor tap and a $190 ZT basically made by the same company with the same lock type (steel liner) will slip off and close either from downward pressure on the spine or a light tap on a heavily cushioned surface.

I'm more curious than upset. As I have said, I have used these knives on the job as a contractor for a couple years without a real world failure. I suppose it's the idea that bothers me more than anything. My weekend driver is a 12 year old mustang. I received a note from Ford that the airbag is defective and could deploy randomly or NOT deploy in a wreck. Obviously, it hasn't been an issue, but I'm still going to get it fixed on Ford's dime.

Like I said, I'm more confused than anything. It's not like the ZT is doing anything cutting edge or special. Steel, titanium, maybe some carbon fiber held together with a pivot and held open with a liner or frame lock.
 
I have owned ZT knives in the past . way back many moons ago. never did spine whacks. sold them because they were just to heavy bulky for me to EDC. they seemed very well made. and I love the designs they come up with . and everything looks very nice when you handle them I recently fondled one at an army navy store and it was very nice . made me want to try them again truthfully. but even knowing that the spinewacks were pretty severe in this video and not knowing what had been to the knives prior or anything else I have to say it has succeeded in making me decide to stay away from them moving forward. when you see the spydercos take it no problem how can you not have doubts? I know no one wants to say "yeah my ZT that I love doesn't have a properly designed/implemented lock " but the question does arise . Why cant they get their locks right? whats really going on here? are they fixing the issue. it does seem legitimate to me. The guy doing the video isn't some teeneager in his room with a knife he got for his birthday beating the crap out of it after throwing it at a tree in his backyard all afternoon. this guy looks to be a collector with a varied wide spectrum of high end knives.
 
Steely_Gunz said:
I think the biggest issue, for me, is a two-part compounded one: how easily the lock was defeated on my personal knives and how many knives are coming back from KAI not fixed.

I really don't want to come across as beating up on ZT. I've purchased 9 of their knives. I have kept 8 of them and gave my 450 to my little brother as a thank you for detailing my car. He loves it. I'm not planning on dumping the others. I probably won't carry the ones that folded as much, but the 3 that held up to 3 or 4 taps are fine in my book.

I guess I'm just confused as to why these premium knives are failing very light stress tests. Why a 70 dollar US made Kershaw made 10 years ago lock does not slip after a very minor tap and a $190 ZT basically made by the same company with the same lock type (steel liner) will slip off and close either from downward pressure on the spine or a light tap on a heavily cushioned surface.

I'm more curious than upset. As I have said, I have used these knives on the job as a contractor for a couple years without a real world failure. I suppose it's the idea that bothers me more than anything. My weekend driver is a 12 year old mustang. I received a note from Ford that the airbag is defective and could deploy randomly or NOT deploy in a wreck. Obviously, it hasn't been an issue, but I'm still going to get it fixed on Ford's dime.

Like I said, I'm more confused than anything. It's not like the ZT is doing anything cutting edge or special. Steel, titanium, maybe some carbon fiber held together with a pivot and held open with a liner or frame lock.
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Very well said.
 
skyhorse said:
Lol, I saw the orignal that started the current OCD epidemic . I've yet to hear of a failure during actual use ?
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I was just referring to the term "whacking off." I've heard them called spine whacks, but that's a new one for me!
 
I've never experienced failure during use.
Nor do I ever understand why I would be gripping the knife in the way shown in the video and whacking the spine.
If gripping the knife properly you are securing the lock with your hand.

As for the test, I tried taps with my ZT: 0055, 0452, 0550, 0560 x2, 0561, 0562, 0609, 0620 and had zero failures.
Maybe I'm lucky? Maybe some slipped through Q and C? Maybe some have been altered/abused?

Either way happy with all mine
 
During actual use your grip helps to keep the lock bar in place. The use of a steel lock bar insert makes the lock slick, and the vibration from the spine wack is more likely to shift it. I would like to see a spine whack done with some mild pressure on the lock bar (like a rubber band) to see if we get a different result.

n2s
 
Many of my ZT and other brands with steel inserts hold up just fine to moderate spine taps. I don't think it's the insert causing failures. More the angle of locking surfaces giving the lock no where else to go under stress but outwards
 
When Kershaw was going through its identity crisis just before/during ZT's infancy, they were putting out some "hard use" boat anchor type knives. I bought the G10 version of the Kershaw Tyrade. It had a really thick liner lock at the time that I could get to move by putting pressure on the spine. I never whacked it but I believe it probably would have closed if I had. When people started poo pooing the Blur I lightly whacked mine against a paperback book and it held. After this thread I batoned my morning bagel with my Cryo and thought I'd spine whack it just to see what happened. It did not close after a pretty hard whack on a counter top covered with a dish towel. If I want a bomb proof folder to take camping I usually grab my CS Voyager with the Triad lock, I have no fears of that one closing on me.
 
Steely_Gunz said:
I think the biggest issue, for me, is a two-part compounded one: how easily the lock was defeated on my personal knives and how many knives are coming back from KAI not fixed.

I really don't want to come across as beating up on ZT. I've purchased 9 of their knives. I have kept 8 of them and gave my 450 to my little brother as a thank you for detailing my car. He loves it. I'm not planning on dumping the others. I probably won't carry the ones that folded as much, but the 3 that held up to 3 or 4 taps are fine in my book.

I guess I'm just confused as to why these premium knives are failing very light stress tests. Why a 70 dollar US made Kershaw made 10 years ago lock does not slip after a very minor tap and a $190 ZT basically made by the same company with the same lock type (steel liner) will slip off and close either from downward pressure on the spine or a light tap on a heavily cushioned surface.

I'm more curious than upset. As I have said, I have used these knives on the job as a contractor for a couple years without a real world failure. I suppose it's the idea that bothers me more than anything. My weekend driver is a 12 year old mustang. I received a note from Ford that the airbag is defective and could deploy randomly or NOT deploy in a wreck. Obviously, it hasn't been an issue, but I'm still going to get it fixed on Ford's dime.

Like I said, I'm more confused than anything. It's not like the ZT is doing anything cutting edge or special. Steel, titanium, maybe some carbon fiber held together with a pivot and held open with a liner or frame lock.
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Agreed on all points. I still love ZT, but... man do I wish they would take this seriously.
 
jill jackson said:
Many of my ZT and other brands with steel inserts hold up just fine to moderate spine taps. I don't think it's the insert causing failures. More the angle of locking surfaces giving the lock no where else to go under stress but outwards
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Definitely the engagement geometry. Lock interfaces and steel liners work great with the correct engagement angle.
 
not2sharp said:
During actual use your grip helps to keep the lock bar in place. The use of a steel lock bar insert makes the lock slick, and the vibration from the spine wack is more likely to shift it. I would like to see a spine whack done with some mild pressure on the lock bar (like a rubber band) to see if we get a different result.

n2s
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Since I'm sending my 0630 in to Kai, I might as well try this. I'll update this post with the results after I try it.

Edit: a rubber band wrapped around simulating a moderate strength grip completely prevented lock failure. I gave it five whacks harder than it took to induce failure before, and there wasn't even a little lock wobble. Unless you grip your knife like a lunatic and somehow don't even touch the lockbar or have grip strength so weak you barely hold onto the knife, there's little to no risk of the knife failing in actual use.

This is why the spine whack a stupid test. It tests a lock in a manner that it was never intended to be used, the hand gripping a knife adds mechanical force holding the lock in place. It's like testing a car for tire speed with the car on a lift and no weight on the wheels, it doesn't work like that in real life, the metric makes no sense
 
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Then I guess I have to find a way to hold my 0909's liner lock in place when I use it, being my hand does not touch the lock when gripped. Maybe I will make some wooden shims and force them into place after I open the knife. Then , I'll have to dig them out after each use , only to replace them again when opened. Toothpicks should work just fine!
 
jill jackson said:
Then I guess I have to find a way to hold my 0909's liner lock in place when I use it, being my hand does not touch the lock when gripped. Maybe I will make some wooden shims and force them into place after I open the knife. Then , I'll have to dig them out after each use , only to replace them again when opened. Toothpicks should work just fine!
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I can definitely see that being a problem for a liner lock.
 
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