Is the Framelock a suitable design for a hard-use folder???

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Cliff Stamp has long argued that the framelock was not a suitable design for a hard-use folder. For example, Cliff wrote:
I have no personal interest as EDC users in liner/frame locks outside of light precision cutters, even then I would prefer a more secure lock because even very slim and narrow blades like the Vapor are capable of doing an awful lot of utility work but are restricted by the lock releasing.

For example, rock the blade into a piece of wood, torquing up and down on the knife to drive the knife deeper into the wood and once it gets too tightly bound then just rotate the wrist to split the wood apart. The vapor easily has enough blade strength to do this, but the lock will release.

If I am going to carry a knife which is so restricted in use that it can't do this I'll simply carry a well made, deeply hollow ground stockman with 1/16" full hard blades. The Alias is a nice looking knife though, I can see how a lot of people would carry it.

-Cliff


I have read where you make similar claims in other threads, virtually all threads involving Sebenza folders or other framelocks to which you reply. I am at odds with your assertion Cliff. You contend that frame locks are very prone to failure by torque loads and are thus not suitable for hard use. In fact, you claim that framelock are so easy to induce failure in that they are unsuitable for all but the lightest cutting, and that they can fail cutting cardboard or a weed. That is a very extreme statement.

I base my objections based on several grounds. First, they are contrary to my own observations. I carried a Sebenza as an EDC for several years, actually I carried several over the years. I carried both the large and small, classic and regular, even a flat grind with dual thumb studs and a swedge for a little while. I used them on a daily basis, cutting acres of cardboard, tons of food prep, utility work and so on. Never once did the lock fail or come close to it. Never once did I fear lock failure, and in fact it was the sense of security from the frame lock that really drew me to the knife, that and it decent cutting efficiency.

I am not alone in my observation, this forum is filled with tradesman, military, law enforcement, and others that have used their Sebenza and other frame lock folders very hard, and there have been virtually no reports of failure. Again, the security and strength of the frame lock is what often times drew them to the knife and is most often a high source of praise.

Consider as well that many people designing hard use knives select the framelock to build their hard use folders around. Strider, Reeves, Anso, Weiland, Mayo, Darrel Ralph, Ken Onion, Cuchiera, Atwood, Emerson, Clark, Korth, Obenauf, Carson. . . The list goes on and on. All these skilled knifemakers who base their occupation on making and designing knives, who have invested small fortunes in machines, time and designs. All are making knives intended for hard use with framelocks. Surely they are not all mislead, misguided and mistaken??? From your posts, it would seem these makers are declaring the earth to be flat.

Still, I thought I would give your claims a fair chance. So I did as you suggest. I took two frame lock knives, a Kershaw Leek and a Benchmade 635 and subjected them to all the uses you describe in the search for the failure you claim will so easily happen. The lock failure that makes frame locks virtually useless I your mind. Though I did these tests with both knives, I will feature the Kershaw, the cheaper, less burly of the pair.
leek0013ge.jpg


All tests were performed holding the knife in the two most often used positions, the saber grip and the hammer grip;

Test #1: Cardboard

As you have described, I took the knife, stuck the blade in, and twisted it around. I twisted to the left, I twisted to the right. I could have twisted all night. I made the cardboard look like swiss cheese The lock does not fail. What happens? The cardboard gets a hole in it.
leek0048rv.jpg

Test #2
rock the blade into a piece of wood, torquing up and down on the knife to drive the knife deeper into the wood and once it gets too tightly bound then just rotate the wrist to split the wood apart. The vapor easily has enough blade strength to do this, but the lock will release.

Yep, I did this too. I rocked the bade into a chunk of scrap lumber and applied pressure to the side, up and down. I twisted, like the devil, the lock held tight. The clip came loose a bit, and I think I stripped one of the body screws a little since I was applying a good bit of force. I was also holding the block together with my off hand so it would not split, I wanted the pressure on the knife. In fact the harder I squeezed the knife, the tighter it locks, the more secure it becomes. The index finger reinforces the lock. That is one of the things that makes a framelock so secure.

leek0055zu.jpg


I have to tell you, I rarely have occasion to do this with a folder, it is simply not what I use a cutting tool for. Then I thought of a situation where people do twist there knives, to make the knife into a make-shift drill to put holes in objects, plastic, wood etc. In bushcraft, you use the knife like that to make a hole in wood to create fireboards (for friction fire lighting, see Ron Hood’s Video #1) and to make certain types of traps, etc.

Test #3:
I took another piece of scrap lumber and used the Kershaw as a drill, spinning it to put holes in the wood. I pretended I was Tom Mayo. The lock never failed. Never came close.
leek0078xz.jpg



How does a frame lock disengage in use? The same way as when it is not in use, you put pressure across the lock bar moving it away from the face of the tang. So when you use the knife, you have to make sure you don’t do that. You can not use the knife in an edge up grip and twist. You don’t push across the lockbar with your fingers or thumb, or it will release. That is not a failure, that is what it is designed to do.

So, yes this limits the way in which you can use the knife, but all locking folders have similar limitations. If you depress the lock on the lockback, pull back the lock bar on an axis, move the bar on a compression, pull the plunger on a plunger lock, push the button on a button lock, they will disengage as well. This is not lock failure, this is user failure.

Here are a couple analogies to illustrate what I mean. When Glock pistols where first being introduced to the American Law Enforcement market in mass numbers (Early 90’s) there were a spate of accidental discharges, and many people tried to label the gun as unsafe, that the gun had somehow failed. Subsequent investigation showed that the guns fired because people did not obey a fundamental rule of firearm safety, they put their finger inside the trigger guard when they did not want the weapon to fire. They pulled the trigger, the gun went bang. It worked as it was designed to, there was no failure of the gun, there was a failure of the user.

Here is a very true story: A few years back my wife took our kids to the library for a reading club meeting. On the way they stopped for gas at a local gas station. My wife pulled her car in on the wrong side of the pump. She got out, realized the gas cap was on the other side, got back in the car, pulled it forward, then backed up to put the car on the other side of the pump. While backing up, she hit the concrete post in front of the gas pump, denting the bumper and rear quarter panel and busting the tail light. The car did not have a “reverse failure”. It did what it was designed to, it went backwards when it was put in reverse and given gas. The car did not fail. As it turns out, the accident was actually my fault, despite the fact that I was 17 miles away at my desk when it happened. You have to be (or been) married to understand the logic in that. You can either be right or you can be happy.

My point is this, if you are using the frame lock in such a way as to make it fail, and tens of thousands of others are using the same lock design without failure, maybe it is not the lock that is the problem. Maybe the lock is fine, and it is just not compatible with your style of use, the way you hold the knife.

Tens of thousands of people believe that the Frame lock is a suitable design for a hard use folder and I think they are right.

My questions for the membership here is simple:

What are your experiences with frame lock folders?
Have you ever had one fail?
If so, under what circumstances?
Do you think the Frame lock design is suitable for a hard use folder?
 
In usual situations I wouldn't use the knife this way...
BUT ...
I want to be able to use a knife for that once in a lifetime, out of the box/design parameters...to pry, drive, wedge, all sorts of stuff that I don't even foresee.

I've always felt that the framelock is a solid lock method....
I never had one fail on me....
But I've seldom had locks of any kind fail. A few lockback have failed due to poor construction of the knife.....IE cheap! Not inexpensive....but poorly made....
The lockbacks failed when I used them as thick two layer sheetrock cutters, putting highHats in ceiling, cutting thru 50 year old wood paneling with sheetrock behind for outlet and switch boxes.......My Sandvik saw failed also. The Spyderco Native S30 I forget what gen...not III tho....came out unscathed and still sharp.

Nice thread!
I like it and the torqueing of the Vapor is wonderful! If only I could get better steel.
But it is an unsung hero of usefulness.

Tom
 
I joined this forum in 1999 and at that time I carried a Puma Duke, a 110 style lockback. At that time there was a lot of discusion about liner locks being superior to lockbacks-and concern about masive lockback failures. So I bought some linerlocks including 2 ECIs which I still have. Later there was a lot of discussion about framelocks being superior to linerlocks and great concern about linerlock failures. I now have 8 framelocks with another on the way. During all this time and a lot of knives I've never had a lock (of any type) fail on me. Having said this my preference is a framelock, but am not afraid to use a well made knife with a different type of lock.
 
But I've seldom had locks of any kind fail.

Yeah, me neither. Most of my folders are actually slip joints, they will fail a spine whack test 100% of the time!! I grew up using Swiss Army knives and Case and Schrade Stockman and Trappers. So a lock on a knife is just an added bonus. Usually when I reach for a folder it is becuase it has a thin balde and edge and I want the cutting performance.

Re: Kershaw
But it is an unsung hero of usefulness.

Yeah, it has a nice blade shape, is very thin, decently acute grind, and came with a scalpel sharp edge. Locks nice too.

If this knife was made in D2, M2 or M42 it would be sweet. Kershaw has some really nice knives at great prices. The AUS6 is decently tough, is easy to keep sharp and takes a fine edge.
 
IRC, the only framelocks I've had fail on me where from the CRKT KISS series.
 
A very well done test. I've had a lockback and a linerlock fail on me, most likely because of them being cheap knives. I applied band aids and kept using them although more carefully. I haven't had a framelock or an axis lock fail on me..yet. It only takes one failure to make you wary, but you can't let that stop you from using any one particular type of lock. Anything is possible no matter how improbable.
 
If I'm not mistaken that is not a Vapor but Leek. Sure looks like my Leek. Still it is a frame lock.

I have never had a liner or frame lock fail on me but I have read of numerous others that have not only had them fail but have been to the ER afterwards. Some of those reports were from twisting in cardboard. Some were other uses that had a twisting motion.

For the record Cliff Stamp is not the only one to point out the failings of the frame or liner locks. Joe and Steve have done some tests with the same results as Cliff or very close.

In my own tests the liner locks and frame locks fail more readiliy from spine whacks than from the twisiting. Actually fail is not the right word because they don't all fail. They just loosen up permanently, especially the titanium ones.

I've got numerous liner and frame lock folders that have less than solid lock ups now after years of carry and it just happened from normal carry EDC uses over time. Buck, Kershaw, Rigid, along with some of my own old hand mades. Some are ti, some are stainless but they all worked a bit off of a tight blade lockup over time and were retired for that reason. Some of the handmade ones I did I rebuilt though.

I am not trying to invalidate your review. It is excellent and I like what you did but you didn't do any spine whacks. In my experience the liner locks are more prone to serious damage from this but spine whacks are not a natural use of the knife so I understand the fact that you didn't do that.

Also, I'm not trying to single out liner locks as the only knives I've retired in my time here on the planet. I have lockbacks that have been retired also. Some recommended to me to retire them from the manufacturer.

Needless to say I have liner, frame, lockback, and axis locks in my own EDC routine. None of the failure scares have swayed me from owning them. I own a Jeep too and everyone knows how easily they roll. Sometimes you have to take what you read with a grain of salt and just move on.

Good test though and will probably give some interesting feedback.

If we still had a rating system you would be getting a positive ding for this post, at least from this member.
 
First off

I twisted to the left, I twisted to the right. I could have twisted all night.

I wrote a song to go along with these lyrics , we can form a band and make millions , sound good ? :thumbup:

Second..

I was leery of frame locks for a long time until I started using them, for some reason the concept seemed destined to fail , and it will if you really try to make it fail. Hell , using that logic Murphy's Law comes into play.
I have made a few kits too that have frame locks and at first I thought it was cheesy , until I used them. My confidence in FL's is as high as it would be with any other lock.
I am still skeptical about my folder with an axis lock , despite the manufacturer's claims :) Then again I dont use that knife at all ! hehe.
Frame locks are fine , if they werent they wouldnt be so popular with manufacturers.
 
knifetester said:
In fact, you claim that framelock are so easy to induce failure in that they are unsuitable for all but the lightest cutting, and that they can fail cutting cardboard or a weed. That is a very extreme statement.

A bit of background, in the following thread :

http://www.bladeforums.com/forums/showthread.php?t=358467

Usafsp argued against torquing tests on folding knives, I pointed out that some torque failures have been seen with really mild torques, yes, even when cutting a weed, just like some spine whack failures, even on integrals, not just liners only need very light pops, here is a recent email :
My buddy and I were just using a pair
of them after fishing, and using the spine to smack some scales off a
plastic board. Just your average cheap plastic cutting board...and to our
surpise his knife folded. I pulled mine out to do the same, and sure
enough, it folded as well.​
This was a guy asking me if he was abusing the knife (Benchmade Skirmish).

...this forum is filled with tradesman, military, law enforcement, and others that have used their Sebenza and other frame lock folders very hard, and there have been virtually no reports of failure. Again, the security and strength of the frame lock is what often times drew them to the knife and is most often a high source of praise.

Consider as well that many people designing hard use knives select the framelock to build their hard use folders around. Strider, Reeves, Anso, Weiland, Mayo, Darrel Ralph, Ken Onion, Cuchiera, Atwood, Emerson, Clark, Korth, Obenauf, Carson. . . The list goes on and on.

The exact same arguement could be made for liner locks. A few years ago there was strong agreement that many of the things which are semi-acceptable now were just horribly abusive.

Inertial openings for example, at one time were the sign of insanity, it was perfectly acceptable to flick a high end custom and have it suffer functional damage in just a few openings. Les Robertson even argued against white knuckle testing claiming it was improper use of a knife.

As more and more makers start to put out knives which stretch the scope of work of folders (and knives in general) this redefines the bounds on normal and hard use. What was once "hard" use, is now normal. Just like when Jim Aston started batoning with Mora's you can't claim this is hard use for a tactical anymore.

In fact the harder I squeezed the knife ..,

In torque releases there is usually little pressure on the knife, there are some compressive forces on the top and bottom of the handle, mainly to keep your hand from rotating around the knife of course.

...all locking folders have similar limitations.

Yes and people are dealing with those, ER for example have solved the accidental grip release issue with lockbacks, and CRK&T have pretty much solved torque instability with liners with the LAWKS, but which still has impact issues, due to the low strength of the steel they use for the LAWKS.

Maybe the lock is fine, and it is just not compatible with your style of use ...

This is obviously the case, but it isn't just me that has reported problems.

[frame locks]

Have you ever had one fail?

Yes, I can release the Vapor as noted in the above, a Maxx (production) in the same way, every liner I have seen has the same behavior, some a lot easier than others.

Some are trivial, some require decent exertion (normal adult male). Plus there are other problems such as the shearing of the lock bar face from the very tiny engagement some integrals have NIB.

Do you think the Frame lock design is suitable for a hard use folder?

Not considering what else is available. Hard use is a relative term, and like all such terms is bounded by the optimal performance.

Informative post.

-Cliff
 
Hard Use is a very relative term.
I wouldnt completly trust any folder to my idea of "hard use". Spine whacks for instance , how good can that possibly be for any folders longevity ? I dont care what brand it is or what its made from , you go "whacking" a spine to split wood or whatever long enough and your lock is going to fail no matter whattype of lock it is.
 
STR said:
Joe and Steve have done some tests with the same results as Cliff or very close.

In order, Joe was the first to systematically test locks and talk about it on the forums, and wrote the FAQ with A. T. Barr. Steve followed and tested much higher impacts, often taping a knife to a stick and using that for heavy contacts.

Others have done similar, Joe and Steve should just get credit as they were the first and not only did a lot of the work with heavy opposition, but pretty much invented a lot of the tests (again with Barr) which are now semi-standard.

One of the problems with one-shot tests is that liners and integrals tend to become unstable over time. The Point Guard I had for example eventually got to the point where it failed really light spine impacts, just spine on palm. Initially it was fine.

I have not seen the same degredation of stability in other lock types. I have even abused quality lockbacks until they started to open, had lots of play, and they are still very stable.

rebeltf said:
...you go "whacking" a spine to split wood or whatever long enough and your lock is going to fail no matter whattype of lock it is.

The Ritter Grip from Benchmade for example has been promoted for exactly this by the designer. It is advancements like this, where makers/manufacturers enhance the scope of work of their tools which force performance terms to be redefined. If you have just one maker, that is all it takes, just one - who is willing to say "Yes, you can do that with my knife." it redefines what hard use means in general for that class and every other knife, no matter how many, are suddenly inferior in terms of scope of work.

-Cliff
 
STR-

Yes, it is a Leek as you indicated.

but spine whacks are not a natural use of the knife so I understand the fact that you didn't do that.

I don't consider the spine whack test to be particularly meaningful. I don't think it relates well to how I use a knife at all. I used slip joints for years, still do. Haven't seen one that will pass a spine whack. :)

Cliff:

I just smacked the holy heck out of the mini-Skirmish and Leek on the edge of my computer desk. Hard enough to indent the wood pretty good. Neither failed. I don't find this convincing of lock stability or strength in the least as it is not something I have ever had occasion to do in real life in decades of knife use. I have slipped and had the knife hit objects at weird angles (cut through rope, too much follow through) but never a true spine whack, it just doe snot accord with my use of a knife. Yes, many people have proclaimed the necessity of this test, Barr and Talmadge for example. I respect them very much, but I still don't find any use for spine whacking. I guess reasonable minds can differ on a subject, eh?

The exact same arguement could be made for liner locks. A few years ago there was strong agreement that many of the things which are semi-acceptable now were just horribly abusive.

Inertial openings for example, at one time were the sign of insanity, it was perfectly acceptable to flick a high end custom and have it suffer functional damage in just a few openings. Les Robertson even argued against white knuckle testing claiming it was improper use of a knife.

As more and more makers start to put out knives which stretch the scope of work of folders (and knives in general) this redefines the bounds on normal and hard use. What was once "hard" use, is now normal. Just like when Jim Aston started batoning with Mora's you can't claim this is hard use for a tactical anymore.

I am not sure what argument you are trying to make here. Your original argument was that framelocks fail under very light use, cutting weeds and cardboard. I don't think anyone would argue those are abusive. I think people use their framelocks far harder and don't have failures.

In torque releases there is usually little pressure on the knife, there are some compressive forces on the top and bottom of the handle, mainly to keep your hand from rotating around the knife of course.

If I don't grip a knife fairly tightly, I can not twist it with a decent amount of force. If I hold it loosely, my hand just spins around the knife.

However, when I was doing my Tom Mayo inpersonation drilling the holes, I was holding the knife by its very eind, not touching the lock at all, since I was spinning the knife and my wrist does not spin in successive 360 degree range of motions.

No added presssure on the lock, no lock failure.

This is obviously the case, but it isn't just me that has reported problems.

Then perhaps you should qualify your assertions about framelocks, noting that while they can be very strong and secure, people who tend to hold or use the knife in a particular manner will want to avoid it, then describe the manner you see failure in.

Not considering what else is available.

What did Sal Glesser report the lock failure point of framelocks as? What were the comparisons for AXIS, Compression, and lockbacks? Was this data published? I honestley don't know, but it would put a lot of the subjective stuff to bed, since I trust Spyderco to run a truly objective test with isolated variables.


Hard use is a relative term, and like all such terms is bounded by the optimal performance.

Yes, many of the pepole making framelocks are promoting them for defensive use, what Spyderco would require a MBC rating for. Others for extreme military applications, the Ti EOD framelocks for example.
 
The Ritter Grip from Benchmade for example has been promoted for exactly this by the designer.

I may stand corrected then. Not wanting to spend the cash and try it for myself I will have to take the makers claims for what they are.
 
I'm happy with my frame locks , I've tested them and narry a problem . I've had liner lock problems , I've also had failures to lock happen in lockbacks , usually caused by crud . ( I've carried lockbacks since 1967 , when I got my first Buck 110 ) . I've tried to duplicate some of Cliff's claims , Ie. weeds , cardboard etc with no sucess . YMMV

Chris
 
Good post, I like the story about your wife's car (Lord knows how many times I have broken something around my house when I wasn't there ;)) I did a similar test back in 1999, I believe, on every frame-lock I owned at the time. One failed, a custom, and I determined it was because the lock bar was too long and thus more prone to flexing when torqued. The maker remade the knife with a shorter lock bar and the problem was solved.

This was before the explosion in popularity of the frame-lock, now every production company seems to offer them and most custom makers of "tactical" and hard use knives offer it as well.

The fact is a well made frame-lock isn't prone to failure from torque even if you can make one fail when you try.
 
rebeltf said:
I will have to take the makers claims for what they are.

This was wrote up in TK awhile back, Doug posts here, maybe he can send one for a pass around so people can try it out.

cdf said:
II've tried to duplicate some of Cliff's claims , Ie. weeds , cardboard etc with no sucess .

These are not my claims, they were pointed out first by Joe who being the guy who wrote the FAQ on testing knives collected a lot of user reports on lock failures. As noted not every lock is equally unstable. The torque failures I have see have been heavier in force and seen in wood work as noted in the above.

stjames said:
The fact is a well made frame-lock isn't prone to failure from torque even if you can make one fail when you try.

Yes it is by defination, assuming that what you are doing is similar to what you would do in using the knife of course.

The lock releases I have see were in direct actual use of the knife at something that a lock back would do easily as would many other lock types.

-Cliff
 
Being 'testers' you have to stick with the facts more than hearsay. So the third party testimony is hard to really call a hard core fact IMO.

Saying that thousands of people carry the knives without issue is not really what I would call a strong argument for any style of lock anymore than it is to say that a Jeep is safe because many people drive them safely.

Of course saying that I heard from Joe that heard from Steve that heard from Cliff that liner locks are unsafe doesn't really go too far in my book either.

It all really boils down to 'personal experience'. Cliff has seen them fail personally and written about it. Joe has seen them fail personally and written about it. Steve has seen them fail personally and written about it. These tests confirm that it can happen which is all that I think any of them ever said. It may or may not have swayed each of them from carrying that type of lock again and it may or may not have had an affect on the readers of their posts.

I think there is one thing that has not been mentioned here. There are good ones and there are bad ones in anything. Some people just can't make a very good or very reliable liner lock. I don't really want to mention names but there are some out there where the lock is just cut entirely too long and made out of entirely too thin of a metal and where the width of the lock is also very small. Common sense tells you that these locks are not going to hold up to much at all before they fail or before the pressure from pushing on them causes a new bend somewhere between the contact point of where the lock meets the blade and the original bend.

I mean anyone knows that it is much easier to bend a long narrow piece of steel or titanium than it is to bend a short wide one. When I see a liner or frame lock cut out over 3/4 of the way down the length of the body of folder I just have no interest in that at all. I personally don't want to be the one that finds out it can fail. If it looks too long to me I figure in my own head that it proabably is. I'd rather have a short wide lock that was a bit harder to shove sideways to close my blade than a long cut thin weak one.

I recently took apart a liner lock from a major manufacturer to reverse the pocket clip for a customer from tip down to tip up. I had to drill and thread the liner and scale to remount the clip in the new position. When I took the knife apart and saw how little metal from the liner lock actually meets the blade to hold it securely locked open I was absolutely amazed.

You cannot tell this kind of thing from just looking at this knife when it is all together but believe me I won't ever own one because now I know just how little there is keeping a user safe from a serious cut. On this particular knife there was appx 1/8" width or perhaps less of steel actually meeting the back of the blade even though there was ample room on both the back of the blade and on the lock itself to recut it to a much larger surface area to secure the blade. From the design it was no accident either. That is how it was cut out.

I happen to like this company so I'll refrain from mentioning it in public. It was a shock though. The only justification I can find for this is perhaps that it is sold as a gents knife but I would not have considered it such at first glance.
 
While I've seen loads of issues with liner locks, I haven't seen them in framelocks. The main thing I've seen in framelocks is that on some, often due to design issues, it's possible that fingers can disengage a lock. I have framelocks that, if I torque the knife counterclockwise and my fingers slip at all (think about if I had to do this under stress, lost minor muscle control, was sweaty, etc.), the lock disengages. On others, that doesn't seem to happen, either because I can't get my fingers to engage the lock enough or it's just too strong to release with a passing slip.

I personally don't recommend liner locks for hard use knives or knives meant for self-defense use (though I do have a few liner locks that for me are the exception), but I feel fine with framelocks. As in all cases, I test 'em when I get 'em -- and that includes spine whacks, which I think anyone thinking about hard use should include in their testing regimen. I also torque them, and simulate hand slipping while torquing which for me is the most frequent problem. I've been watching Cliff's statements carefully, seeing if anyone else duplicates his results.

Joe
 
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