Zero Tolerance Liner Lock Closures?

[midnight flyer]

Friction, titanium, or whatevee, that’s not the solution. The solution is for them to fix their damn lock geometries.

Yes. This.

And to find a way to make things right with those that bought into their claims of "proudly overbuilt". When you pound your chest that hard crowing about the toughness of your product you really need to deliver. Obviously, there are problems with more than a few of their knives.

If they don't have the integrity to do the right thing and behind their product and warrant their product they should atleast consider how fast negative reports, videos, blogs circulate in today's internet world. No doubt few outside the knife world know about this now, but it was take a lot for this to turn into a mushroom cloud. Anytime I do research or I am just looking around, BF always comes up and that means thousands could see this thread and more like it. Since most people seem to at least partly believe what they see on the internet (including me) that has to eventually affect ZT's sales.

Seems to me that even if they do the right thing for the wrong reasons, they really need to address the lock issues sooner than later. When you have a chance to make things right, you have to seize that opportunity.

Bad enough that somewhere their QC, manufacturing and/or engineering got out of whack, but apparently, they aren't making the most of their second chances, either.

Robert

 

[Steely_Gunz]

I wouldn't steer away from ZT because of this.
If its not your flavour that's one thing.
I have 10 plus... love them, no issues with my locks all hold up.

I have yet to see anyone send theirs in with proof to say it wasnt fixed.

My 350, as I have stated but maybe didn't go on about, still closes with lighter than I would like static pressure to the spine.

I didn't really test for a complete fix after I got it back (totally my fault) because 1) I just assumed mine was a fluke. I have never heard if a ZT failing a spine pressure test. 2) I elected to have the serrated blade replaced with a plain edge. I figured the issue was in the grind on the blade, not the lock itself.

It might be a little more secure, but it still slips off. I'm not really worried about sending it back in. I just use it and know that it's a potential issue.

Once again, I'm not super worried about the lock issues. If I were flying to be using a folder to go blade to blade, then maybe. Actually, as unlikely as that is, it's the main reason I retired my 630 of all my folders, that's the one I bought specifically for potential self defense. It fails a spine tap (not whack) pretty easily.

 

[bambam99]

My 350, as I have stated but maybe didn't go on about, still closes with lighter than I would like static pressure to the spine.

I didn't really test for a complete fix after I got it back (totally my fault) because 1) I just assumed mine was a fluke. I have never heard if a ZT failing a spine pressure test. 2) I elected to have the serrated blade replaced with a plain edge. I figured the issue was in the grind on the blade, not the lock itself.

It might be a little more secure, but it still slips off. I'm not really worried about sending it back in. I just use it and know that it's a potential issue.

Once again, I'm not super worried about the lock issues. If I were flying to be using a folder to go blade to blade, then maybe. Actually, as unlikely as that is, it's the main reason I retired my 630 of all my folders, that's the one I bought specifically for potential self defense. It fails a spine tap (not whack) pretty easily.

Thanks for sharing your experience.

I had read a few posts about people's locks failing but posters were ranting about ZT not fixing the problem yet I hadn't seen anyone send it in and have ZT not fix it.

I mean if I had as many failing as some of the posters say, I'd be sending them all in with a video or letter explanation and see what they say.

Especially If they deny fixing it... put that on the web and see how quickly that would change.

I carry my ZT 620cf as my duty carry daily, for any use but also for that use you mentioned in mind

 

[firefighterguy]

Well you are the first person I've heard of sending it in.
What did ZT say ? Email or letter saying why it wasnt fixed ?

I sent it in and they said they couldn’t get it to replicate the problem but they went ahead and changed out the lock insert anyways. The knife was returned to me worse off than before. I posted some pics earlier in the thread. The lockup was at maybe 10%. When I sent it in the knife would fail after 2-3 taps to my hand. After sending it in the lock would fail the first tap to my hand. I’ve never spine whacked this knife on any hard surface. I’m simply just using the palm of my hand.

ZT said it passed their QC.

 

[firefighterguy]

ZT left me a voicemail saying that my knife is on its way back. They said it passed through the hands of two warranty techs and the production manager and all said it has passed their inspections. Fingers crossed they fixed it!

 

[whp]

I have a 0551 that developed lock rock after about a year of moderately hard work use. I called ZT and spoke to an excellent service rep. She recommended returning it for repair. They replaced the blade. After the return the lock up was tight for a couple off months and then the lock rock returned. Not as bad as the first time, but I quit using the knife.
I also have a 0561 and a 0350 which I haven t used as much as the 551, but their lock up has remained tight.
I ve never tested these knives with spine whacks.

 

[Night Rider]

That looks darn right dangerous. I just don't get ZT! they seem to have some real issues that they are not addressing. I hope they have some very good layers cuz I see lawsuits in the future if they keep producing Crap like that. If I were to cut my finger tendons while using one at work I would use my good hand and dial up a personal injury layer to take my case pro bono cuz i'm sure ZT has some deep pockets.

 

[whp]

ROCK 6, great post!

So true... no matter the situation, there will always be unhappy folks. Like you, I am not ditching my ZTs, but as posted earlier my newest work knife as of about 2 weeks ago is a CS Ultimate Hunter.

Everyone that has doubts about ANY product should simply stay away. Wayyyy to many high quality work knives out there at better prices than ZT like the CS Ultimate Hunter. I truly hope they get all of this straightened out, from top to bottom, but it's kind of looking like it might be a slow roll.

Robert

My Ultimate Hunter has been an outstanding outdoor work knife. Really holds an edge.
I don t buy any knives that open only with a flipper.
And now, I m avoiding frame locks and most knives with only metal handles.
As mentioned above, there are other choices.

 

[bambam99]

I sent it in and they said they couldn’t get it to replicate the problem but they went ahead and changed out the lock insert anyways. The knife was returned to me worse off than before. I posted some pics earlier in the thread. The lockup was at maybe 10%. When I sent it in the knife would fail after 2-3 taps to my hand. After sending it in the lock would fail the first tap to my hand. I’ve never spine whacked this knife on any hard surface. I’m simply just using the palm of my hand.

ZT said it passed their QC.

Thanks for sharing that!
I might have missed your earlier post.

I'm hoping that they have fixed your issue now
And will fix any others that have these issues.
That will make or break this company for me.
If they stand behind it and fix issues, I'll stand behind them
If not... well they will have lost me for future purchases.

 

[Tommy-Chi]

I was thinking of buying a ZT at some point, but there is enough evidence out there that I don't think I will pay $200 plus for any ZT. I can understand folks chiming in and saying that their ZT's are fine, but those who are so vociferous in defending ZT no matter what, to the point of accusing those Youtubers of fabrication or fraud, are going too far. Most ZT's are too big and heavy for my liking anyway. And even if only a small percentage of their knives are affected by this problem, the refusal or inability to fix the knives sent back is inexcusable.

I was one of the original complainants in another and THIS thread, speaking abt how a ZT 0450FCZDP lock had collapsed after I placed light pressure on the back of the spine and it cut my hand. I sent that knife in for customer service and it now works perfectly. NO FAILURES TO LOCK IN WELL OVER 100 OPENINGS, and it locks tight as a drum!

That was my 3rd ZT and I am pleased to report that I bought a 4th ZT, a 0095TANBLK in S90V, and it is beautiful...and I plan to buy a duplicate copy.

This is a problem that ZT is going to have to address, but I'm not going to stop buying ZTs, and I have 4 more on my short list to buy. I believe in the product 100%....so don't give up hope just yet.

 

[rogatsby]

I was one of the original complainants in another and THIS thread, speaking abt how a ZT 0450FCZDP lock had collapsed after I placed light pressure on the back of the spine and it cut my hand. I sent that knife in for customer service and it now works perfectly. NO FAILURES TO LOCK IN WELL OVER 100 OPENINGS, and it locks tight as a drum!

That was my 3rd ZT and I am pleased to report that I bought a 4th ZT, a 0095TANBLK in S90V, and it is beautiful...and I plan to buy a duplicate copy.

This is a problem that ZT is going to have to address, but I'm not going to stop buying ZTs, and I have 4 more on my short list to buy. I believe in the product 100%....so don't give up hope just yet.

Thanks for the follow-up, and that's good to hear. But my view is that at those prices and the way ZT knives are marketed, sending knives back for lock issues like this is unacceptable.

One suspicion I have is that there are many frame lock and liner lock knives (not just ZT) that suffer from this problem. I think frame locks and liner locks can be very secure, but the obsession with smoothness in opening and closing seems to have made some of these knives less safe. Ironically, the more expensive knives seem to suffer more from this, because more smoothness is expected of them.

 

[BD_01]

What proof do you need? I sent mine in and it wasn’t fixed. As have others.

firefighterguy your ZT is still back at the mothership for the second try, right?

 

[firefighterguy]

Correct. It’s on its way back again. Supposedly fixed for sure and personally approved by ZTs production manager.

 

[BD_01]

Correct. It’s on its way back again. Supposedly fixed for sure and personally approved by ZTs production manager.

Be sure to let us know how it’s turned out.
I’m seriously hoping for the best.

 

[stiletto100]

My 0350 locked up really tight, it would take a really hard thrust to force the blade .

 

[rhino]

After I saw the video in the first post, I checked my ZT0301 and ZT0452CF. I could not detect any "lock rock" and the engagement between the frame lock and the base of the blade looks solid. I took a few whacks on them just to make sure and neither failed. I won't be whacking them again.

 

[Kaizen1]

Interesting thread. I did some moderate level spine whacks against my knee on my ZT 804CF. It was as hard as the spine whacks against palms and knees in this thread, but not as hard as against the tape roll. The knife showed no lock rock or any other kind of play before this.

Here I opened the knife, but intentionally set the lock as early as possible before doing the spine whacks:

Here it is after spine whacking. No failures. This is also where it normally locks up at after normally opening with the flipper:

Here it is after pushing the lock bar in as far as I can without going crazy on it:

The lock shows no play after spine whacking.

 

[Kaizen1]

Did the same with my 0452. I've had this one for years now. It never has shown any sort of blade play.

Here it is after trying to set it as early as possible before spine whacking:

Here it is after spine whacking. No failures.

Here it is after trying to push the lockbar over as far as I can:

No play after spine whacking.

 

[Lapedog]

My 350, as I have stated but maybe didn't go on about, still closes with lighter than I would like static pressure to the spine.

I didn't really test for a complete fix after I got it back (totally my fault) because 1) I just assumed mine was a fluke. I have never heard if a ZT failing a spine pressure test. 2) I elected to have the serrated blade replaced with a plain edge. I figured the issue was in the grind on the blade, not the lock itself.

It might be a little more secure, but it still slips off. I'm not really worried about sending it back in. I just use it and know that it's a potential issue.

Once again, I'm not super worried about the lock issues. If I were flying to be using a folder to go blade to blade, then maybe. Actually, as unlikely as that is, it's the main reason I retired my 630 of all my folders, that's the one I bought specifically for potential self defense. It fails a spine tap (not whack) pretty easily.

My 0620cf failed embarassingly light spine taps as well. Bending the lockbar just slightly more in completely remedied the problem. You could potentially try doing that to youre.

 

[Steely_Gunz]

My 0620cf failed embarassingly light spine taps as well. Bending the lockbar just slightly more in completely remedied the problem. You could potentially try doing that to youre.

I actually plan on doing that in the near future when I have time to pull the knife apart. The nice thing about the 630 is that it uses a nut over a proprietary fastener.