Lock failures? Springs broken? Assisted letdowns?

A

Aldebaran

Joined
Sep 18, 2004
Messages
335
There are many lock mechanisms now, and many have springs involved. I would like to hear your experiences with any failures you have experienced.

Me? Every design I have had that involved a spring has failed at least once.
Kershaw Cryo II, spring fails every month if used.
Zero Tolerance ZT0566 spring fails every couple of months if used.
Benchmade Ritter Grip, omega springs failed within weeks of new (years ago and hasn't happened again).
Benchmade Mini Ambush, indraw spring failed within weeks.

So I have a distrust of springs in lock designs, rational or not, from my experience.

I have also seen many reports of lock failures in knives. Most of these involve abuse but some have been outright surprising failures in normal use. One example is the Cold Steel Swift.

I would like to hear about those who have had failures of springs, locks, or assisted mechanisms. How, why, when where.

IMHO, the simpler the better. I now lean toward liner locks, frame locks, back locks, compression locks, and tri-ad locks. If I see an extra spring somewhere in the design to hold the knife closed or open, I avoid it.

What are your stories?
 
I've had several liner lock failures, always opening when they shouldn't, one CRKT Apache, carried point down, opening from gradual rear pocket lip friction on the dual thumb studs, the point poking rigidly out through my rear pocket, and slicing a finger bad enough to send me to the hospital.

Another Liner lock failure was the giant Al Mar Quiksilver that opened fully open during a fall on the ground, and thoroughly destroyed its edge on rocks in the process... With such a narrow blade, there was no working it out...

A cheap $20 double action auto I bought in Germany would sometimes fail to lock on opening. Should have bought the much heftier and better "traditional" side opening auto for a similar price...

Early Benchmade AFCK could flex in my hand to the point of the liner lock disengaging. The very first Spyderco Military to come out, in 1995, had screws that screwed directly into the actual G-10 of the G-10 scales (no I am not kidding), and most of them stripped out on the first disassembly...

Never had a problem with the Spyderco Civilian or the big AL Mar SERE. A spring keeps them closed...

I would really like my SOG Fatcat if it wasn't for the recurved edge... Another spring dependent lock design that really works.

I avoid all liner/frame locks, although I still have my early Smith and Wesson 911 "First Response", after 20+ years, primarily for its spring loaded glass breaker... Ironically, it uses a rigid Zytel bar mounted on a hinge that has separate springs: The action of this is softer, yet very secure, and I find it oddly appealing compared to a "real" liner lock...

$_57.JPG


Gaston
 
Last edited:
Gaston444 said:
I've had several liner lock failures, always opening when they shouldn't, one CRKT Apache, carried point down, opening from gradual rear pocket lip friction on the dual thumb studs, the point poking rigidly out through my rear pocket, and slicing a finger bad enough to send me to the hospital.

Another Liner lock failure was the giant Al Mar Quiksilver that opened fully open during a fall on the ground, and thoroughly destroyed its edge on rocks in the process... With such a narrow blade, there was no working it out...

A cheap $20 double action auto I bought in Germany would sometimes fail to lock on opening. Should have bought the much heftier and better "traditional" side opening auto for a similar price...

Early Benchmade AFCK could flex in my hand to the point of the liner lock disengaging. The very first Spyderco Military to come out, in 1995, had screws that screwed directly into the actual G-10 of the G-10 scales (no I am not kidding), and most of them stripped out on the first disassembly...

Never had a problem with the Spyderco Civilian or the big AL Mar SERE. A spring keeps them closed...

I would really like my SOG Fatcat if it wasn't for the recurved edge...

I avoid all liner/frame locks, although I still have the early Smith and Wesson First Response, after 20 years, primarily for its spring loaded glass breaker... Ironically, it uses a rigid Zytel bar mounted on a hinge that has separate springs: The action of this is softer, yet very secure, and I find it oddly appealing compared to a "real" liner lock...

smith-wesson-first-response-knife-model-sw911-4.gif


Gaston
Click to expand...


Didn't think you could outdo yourself.

Great picture of your S&W also. :thumbsup:
 
Never had any failures of the things described in the op.
 
Last edited:
Ive never had any springs break or lock of any kind fail ... I prefer to deassist my ZTs just because most are so smooth without the assist ... but I do have a 566 I left and its still opening as strong as day one after a couple years regular use. And a Kershaw leek I don't carry but it's used alot in the house no spring issue.
 
Gaston444 said:
I've had several liner lock failures, always opening when they shouldn't, one CRKT Apache, carried point down, opening from gradual rear pocket lip friction on the dual thumb studs, the point poking rigidly out through my rear pocket, and slicing a finger bad enough to send me to the hospital.

Another Liner lock failure was the giant Al Mar Quiksilver that opened fully open during a fall on the ground, and thoroughly destroyed its edge on rocks in the process... With such a narrow blade, there was no working it out...

A cheap $20 double action auto I bought in Germany would sometimes fail to lock on opening. Should have bought the much heftier and better "traditional" side opening auto for a similar price...

Early Benchmade AFCK could flex in my hand to the point of the liner lock disengaging. The very first Spyderco Military to come out, in 1995, had screws that screwed directly into the actual G-10 of the G-10 scales (no I am not kidding), and most of them stripped out on the first disassembly...
Click to expand...
Interestingly, I also have two of these knives- the CRKT Apache and an early Benchmade Mini AFCK. I carry the Apache inside the waist band in the appendix location, so it's basically pointing at my gut all the time. Awesome knife and I never had a problem with the liner lock; it's pretty stout. The liner lock on the Benchmade, however, failed on me (minor usage; no injuries, luckily). I sent it back to BKC and they fixed it. Due to this incident, I do not trust liner locks and while I still use them, I'm very leary and very cautious. There are much better/safer designs out there.

Just my $.02
 
For over 50 years I carried nothing but slip joint knives and for about the last 45 of those years I carried a Buck 303, Cadet. I used that little Buck to strip electrical control cables and I never had a failure. There were no springs, no locks, and the only assist was my fingernail. I used the sheepsfoot blade to strip cable and I have one retired knife that has been sharpened so many times the blade looks more like an awl than a sheepsfoot.

For about the last 2 years I have been using various lock blade knives, mostly a mini griptilian or a Sage 5. I do appreciate the better steels and so far I like the Sage's compression lock but since I no longer work in the field I don't stress my knives like in the past.

I have never had a failure with any knife whether slip joint or lock blade. The Axis lock on the mini-grip is sure fun to play with and mine has more than a few hours of play time. I have also spent a lot of time playing with the compression lock on the Sage. Another knife I like to play with is my Boker Plus Urban Trapper. It's amazing how easily it flips open though the titanium lock does occasionally stick very slightly.

I rambled on to say I have never had a knife fail other than after years of use I have had a Buck develop some side play on the blade, but I don't consider that a failure. I use my knives to cut. I sharpen them when they need it and I clean the pocket lint out of them when I notice it. I don't know if I am doing something right or if I have just been fortunate. At my age I don't use knives like I used to so I doubt that I will experience any failures.
 
I wouldn't call a spring assited knife torsion bar "breaking" is not a failure. Many companies say it will happen after x-amount of opens. It is like oil and window washer fluid... it is foolish to think you will never have to replace it in your car. I have many Zero Tolerance 0566BW's, the torsion bars to break every once and awhile (after opening the knife thousands of times I fidget with my knives often), that is why ZT Will send you a pack of 10 and it takes 10 seconds to replace. Nothing really to complain about there, under normal use and not excessive fidgeting they will last a long time. For springs in locks, never had an omega spring break after a lot of opening and closing on any of my benchmades.
 
Well, not a failure per se, but the only two knives that opened in my pocket(s) and cut me where two assisted (CRKT Ripple 2, Kershaw OSO Sweet) and the only third assisted I currently own (CS Swift) is a first generation Swift that has the spring problem, but hasn't "popped" out yet after hundreds of openings...all three in the pic below:

ilJGc6l.jpg


I've had 2 linerlocks and 1 framelock burst and break on me, one of them cutting me badly, but they were admittedly cheapo knives from non-reputable brands (AKA gas station knives).
Never been cut by a TriAd lock, a fixed blade or a slipjoint/SAK
 
I have an old CRKT K.I.S.S. that has had the liner lock fail in the open position a few times.
 
I've been lucky I guess, no failure to speak of.
When you buy a cheap knife and it doesn't work right, is it knife failure or consumer failure?
 
I have used a ZT0350 over the last 8 years and never had any issue with the torsion bar

Some with BM omega spring or the mid-backlock of my Delica (this last one I have only for 1 year, so I won't make any final statement)

IMO springs are fine, but.... As you said the simpler the better and as time goes I am leaning toward manual, one hand open/close, on washers basic folders.

PM2, sebenza, etc.

I am still very enthusiast when carrying my other knives but I enjoy simplicity more and more
 
I've never experienced any of the noted failures.

Nor has anyone I know personally.

I wouldn't call myself "lucky"... I suppose I'd be more inclined to consider you "unlucky".
 
Crkt my tighe, assisted- used for rough condition work carry since 2008, never failed, ever. Assist opens so hard it will crush debris between the stop and the blade, locks up great. So, no failure on that "cheap, unrefined, un-snobworthy" piece. Ever. Except handle ergos. Pointy.

Kershaw Cyclone, daily carry knife otherwise from 2006 onward, 10's of thousands of torsion cycles and several dozen disassembly sessions over its life. Never a failure once.

I dont worry about the reliability of mechanisms like that much. If you got a bum spring, you will know it in a few hundred cycles. If it goes longer, its likely done 'right' and wont fail until you do something stupid with it (like 'adjusting' it).. I have to call bullshit on the stories of speedsafe springs breaking every month of use, there's just too many semi loads of knives with that same system that work flawlessly for years so far for me to think they fail as commonly as kickstarter campaigns.

That fella with the buck 303: your knife has 2 springs- where do you think that 'walk and talk' comes from? What holds them closed? Personally I have seen more broken springs on traditional knives than anything, and when they go out, it actually does completely ruin the knife. it wont stay open, it wont stay closed, sometimes the blade can literally swing a 270 degree arc in the handle if the spring totally breaks and drops the leg the blade walks on. When an assist spring breaks, usually you still have a safe knife to use. Just wanted to point that out..
 
I'll never get another frame lock again. After a few failures of that lock in general, I don't trust them with MY fingers! I get lock backs now.
 
I have an Ontario Rat 1 that had a wonky detent when I first got it. Moved the clip to tip down and carried it for a few minutes before it opened up in my pocket. Tip poked through my pants and got me in the hand...
The detent ball wasn't lined up well with the detent hole and caused the blade to work out and expose the tip. I assessed the problem after putting it in "time out" for a few days and was able to fix it by slightly bending the liner down and aligning the ball/hole. Really more of a manufacturing defect I suppose than a lock failure.
 
Aldebaran said:
IMHO, the simpler the better. I now lean toward liner locks, frame locks, back locks, compression locks, and tri-ad locks.
Click to expand...
Not trying to be pedantic here, but each one of those mentioned either have or are springs...

The only times you wouldn't encounter spring are:
A) most traditional fixed blades
B) a non assisted folder that used a pin to secure the blade open, not a spring/latch/lever.
----
It is unfortunate that you have had springs fail. I have user traditional folders that are close to 100 years old and the stock back springs are fine...

Try a Manix 2, the coil spring tends to be secure, simple and has quite a long life.
 
There are really only 2 style of locking styles:the ones where the tangs of the blade must push aside something in order to close (liner and frame locks) and the ones where the tangs must crush something in order to close (back locks,compression,ball bearings etc).There for i would always go with the second cathegory of locks,and as for the spring assisted its just a gimmick,something which can go wrong.
 
You must log in or register to reply here.
Back
Top