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

[Cliff Stamp]

I wrote Ka-Bar ...

Have you discussed it with Dozier?

-Cliff

 

[STR]

I did send him an email about it right before I returned the first one to Ka-Bar. He didn't reply. I figured it was due to the fact that it only has his name on it as his design and took that as a hint to bring it to Ka-Bars attention, which I did through Carol Hnat the cust. srvc. rep. there. She told me via an email reply that my pics and info were forwarded to the proper people. I even offered to send them this knife to examine for themselves in that letter but it wasn't taken seriously I guess.

I never heard anything after that. I guess it is easier to let them be. Maybe they are not having a large return problem with lock/stop defeat and the count they get back is a justified risk. ??? I don't know.

All I do know is I fixed my own and can trust the blade stop now. Doing that did require doing some modification on the blade to make it close over the newly installed stop pin but that was not a big deal at all. I have, since those pictures also taken off the top or spine wing tip because it was always right where I wanted to put my thumb when using the blade.

 

[LaBella]

yes, framelocks make excellent users!

:thumbup:

 

[Cliff Stamp]

In reference to some comments exchanged with knifetester on jamming, I did some experimentation with the liner on the small Sebenza and I can fully engage it with just pressure from the thumb in a pinch, ~10 lbs, at this point it becomes very difficult to unlock (the pressure indents the flesh of the index finger).

From doing this a few times to check the "stick" and general carry and use, including a few dozen intertial openings, the lock engagement is more than 4/5 across the tang. It has wore just as fast as the Kershaw Vapor, which has actually seen far rougher use as the blade profile is stronger so I use it to twist split wood and such.

-Cliff

 

[STR]

I'd be a little afraid of what twisting motions could do to the bushings on the Sebenza. If they are sensitive enough for Chris to warn against hard flicks opening the knife you have to wonder. Do I understand that correctly, or is it the lock that is the sensitive part for hard flipping to open the blade?

 

[knifetester]

From doing this a few times to check the "stick" and general carry and use, including a few dozen intertial openings, the lock engagement is more than 4/5 across the tang. It has wore just as fast as the Kershaw Vapor, which has actually seen far rougher use as the blade profile is stronger so I use it to twist split wood and such.

-Cliff

Re: 4/5 blade travel.

Take the knife apart, reassemble then see what it is. On several Sebenzas, this would "reset" the lock so that it travels much less across the tang.

As to wear vs. Kershaw, yeah the stainless steel, even cheap stainless, is much harder than Ti. It will wear slower. Thatis also why you see a ton of scratche son the slabs with just a little use, and much fewer on the Stainless Kershaw. I would say that is expected behavior.

Ti offers other advantages over steel frames, including: light weight, much better hand feel, does not transfer heat and cold to the hand as much in harsh conditions as it is less conductive, etc.

I will admit though Cliff that I am uterly confused about something. You have written many, many post condemning liner locks and framelocks. I would venture to say hundreds. Some of these statements are very extreme, you have basically writtent hat the liner lock is such an insecure and unstable lock design that it is almost worthless.

I.e., the post that started this thread:

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.

Yet, in your review of the Spyderco Militarywhich is a liner lock, you sue the knife for a much wider scope of work. In example:

The Military was then used extensively in the kitchen. Through the tip it easily cut cut meats and trimmed fats, even tomatoes and plums were smoothly cut without excess slippage. Hard synthetic ropes were no problem, and various fabrics, paper, cardboard, and rubber tubing were also neatly cut.

Pointing some ends on a hardwood dowel (basswood) the Military required 3.78 +/- 0.54 slices. The performance was high due to the thin blade stock and thin and acute edge bevel, combined with the excellent leverage due to the edge being fully sharpened right to the handle. With a 50 lbs push, the tip sank to 266 +/- 8 pages into a phone book, with a hard stab (icepick grip), the penetration was 681 +/- 35 pages.

On binding vegetables like carrots and turnips, it continued to do well. . .

The Military easily handles light vegetation as this mainly requires just a very sharp edge. . .

The Military is readily capable of roughing out large amount of wood in a short period of time.

For carving notches and in general shaping of wood the Military works well for hogging off material and precision carving.

The Military was carried daily for an extended period of time (months) and used for all cutting chores.

You list specific tests for cardboard, carpet, etc.

In contrast, on this Military the liner lock held secure under "white knuckling" as well as various spine whacks. Heavy torques on the blade (split a piece of 1x4"), did not disengage the lock, nor did a combination of torques and vertical loads. In short the lock was stable during all testing, and held up fine under the heaviest of the dynamic cutting.

My confusion is this, you write that the liner lock design is so insecure and unstable that its scope of use is harshly restricted. Yet, you use a Liner lock folder for a wide range of cutting chores, including the ones you insist it will fail doing. Yet, the Spyderco does not fail.

In one of your your earlist reviews, the Mini-AFCK (another liner lock) you do some pretty extreme testing, no failure:

In regards to toughness, I was mainly concerned about tip strength as the point is very fine so I spent some time ramming it into wood, twisting it, and pulling to the side. I also did some light prying by popping out heavy staples and such. I did not repeat these tests with the Endura as I have broken the tips off of other stainless folders (440C) with thicker point doing similar work.

Can you explain the discrepancy?

If some liner ocks fail, and some don't, then perhaps it is not a problem with the Walker design, but rather a problem with execution. Perhaps liner locks or framelocks require more care in fit and finish. I would guess this is pretty important, is well fitted liner lock is probably much more secure than a liner lock that is poorly fitted? I would guess that precision here is more important than in some other locks, like Lockbacks.

With lockbacks, Sal Glesser has indicated that a slight bit of blade play will not interfer with lock strength, right? But wouldn't blade play or other poor fitting have a greater chance of making the liner lock fail?

Perhaps it is the nested design of the Spyderco? Maybe that makes it a more secure lock than any other liner lock?

Have you reconsidered your stance on liner or frame locks? I just can not see how your version (framelocks are so insecure that they are nearly worthless, can not even cut a weed or cardboard with out failure) is more correct than virtually everyone else's opinion, i.e. Framlelocks are suitable for hard use knives, and virtually universal agreement that thay are suitable for moderate use, such as the tasks you claim they will fail on so trivially.

 

[STR]

From the link pasted below.

"Titanium has a high strength to weight ratio.

- Titanium has superb spring retention qualities, without the

necessity of any heat treatment. A titanium spring will recover

from a severe load that would permanently deform a steel spring

of the same cross-section.

- Titanium galls to other metals -- it seizes to them, rather than

slipping past them, when they are rubbed together under tension.

This makes titanium useless for moving parts, but ideal for parts

that are meant to seize, such as the end of a liner engaging the

end of the tang of a folding knife blade. (Note added by STR: So as you can see this characteristic of seizing up is one of the so called benefits of Titanium)

- Titanium can be electrolytically toned to a wide range of

attractive colors."

http://pweb.netcom.com/~brlevine/liners.txt

Even still with the attractive color advantage and the lock siezing to the metal of the tang to form a better more secure grip I've had better luck with stainless steel liners overall. The Spyderco Military has a hardened stainless liner lock which would explain why it did well in Cliff's tests I think.

 

[Gryffin]

I'd be a little afraid of what twisting motions could do to the bushings on the Sebenza. If they are sensitive enough for Chris to warn against hard flicks opening the knife you have to wonder. Do I understand that correctly, or is it the lock that is the sensitive part for hard flipping to open the blade?

I wouldn't worry about the bushing, it's plenty stout. And they don't really take any of the stress; the pivot screw does.

I think some people misunderstand the function of the Sebenza bushing. All it really does is maintain a very precise spacing between the handle slabs, which in turn maintains a very precise drag between the slabs, washers and blade. That's the reason why pivot screw tension has no effect on the force required to open the blade, unlike knives with adjustable screw pivots.

I suspect that the issue with flicking has more to do with wear on the locking surface. As Cliff and others report, too much pressure can cause jamming; that's not unsafe in itself, but having to use too much force to unlock it will accellerate wear the locking surface.

(The part that really takes a beating when flicking is the stop pin. But the stop pin of the Sebenza, like most folders I know, is extremely stout.)

 

[knifetester]

STR,
Just a side note, I beat the hell out of you liner lock Whittlejack folder trying to get it to fail. No lock failure under extreme spine whacks and torque loads. Rock solid lock. The wood handle scale cracked.

 

[STR]

If you want, send the knife back to me and I'll replace that handle scale for you. Luckily I still have some of the same wood on hand yet.

Good to hear the lock worked as I had hoped it would.

PM or email me if you need my address.

Steve

 

[JoHnYKwSt]

I just tried to jam the locks on a couple of my sebenzas. I've done this before and remembered it was not a problem, but decided to try it again after reading the previous posts. Pinching the lockbar with quite a bit of force caused very little sticking when unlocking, in three of my small sebenzas. One of these sebenzas is my EDC which has been cycled something along the lines of 15,000 times (very rough estimate). On this sebenza there was almost no sticking.

The 2 large sebenzas that I tried this on fared differently. Both stuck a pretty good amount. On one it was enough sticking that I could imagine it being a problem if lets say Cliff's brother were to use it and thus causing it to stick on a regular basis.

Cliff,
I dont flick open my knife very often but my EDC is about 90 percent accross the tang. When I first got the knife I did worry about lock wear so I decided to test it. I think most of the wear is caused by the flattening of the stop pin sleeve -- after the first 1 or 2 years my lock seemed to have stabilized, 5-6 years later.

Another note, other than a single incident in which the person modified their lock, I dont recall anyone on the forums wearing out their lock.

 

[chris in mo]

Ok this is a little off the main topic but I have to post a point. Every time I read one of these threads about which lock is superior, so and so won't buy a knife with such and such sort of lock etc.... I have to stop and think about how long have folding knives been around and how long have locking blades been in vogue? Look at generations of individuals many of whom used knives much more frequently in agricultural and industrial roles than most of us do now.

It is a good thing they didnt know that a knife with anything but the latest super duper techno lock made from the latest wonder steel was a complete piece of garbage and totally unsafe to use. I don't recall seeing scores of the older generation missing fingers or badly scarred from the horrendous wounds they received and boys carried knives on a daily basis from the time they were in grade school. Perhaps it was because they understood that a knive is a cutting tool, not a chopping tool, or a pry bar, or a shovel (add your favorite absurd hard use application here). How far we have advanced in technology only to completely lose all common sense. I wonder how many ancient cultures would see one of us hammering a knife through a log and shake theire heads about the poor moron who does not realize that an axe head should not be shaped like that and could show us how to do it correctly with a properly selected and shaped rock!

I still think the safest bet is to use your knife what it is intended for and if you need an axe, tree stand step, trowel, jackhammer etc... get the right tool for the job. You will probably accomplish it much quicker and with less damage to your knife or yourself. Perhaps I am missing something here though.............

 

[knifetester]

I still think the safest bet is to use your knife what it is intended for and if you need an axe, tree stand step, trowel, jackhammer etc... get the right tool for the job. You will probably accomplish it much quicker and with less damage to your knife or yourself. Perhaps I am missing something here though.............

You are right, a pry bar is better for prying, a shovel better for digging, a hammer better for hammering than a knife. However you probably don't always have a hammer, prybar and trowel, stand step with you and it is impracticable to do so.

IF you are on a canoe trip 15 miles down river and you need to drive some tent pegs, do you padle up stream 15 miles to get your hammer or use the poll of your axe? To split some logs, do you sprint the 12 miles overland to town to get a maul and wedges?

Hopefully not. Hopefully you have the skill, knowledge and imagination to improvise and use the tools you do have.

One reason a knife is such an important tool is that it is so versatile. A well built knife can be used for splitting wood, limbing trees, scraping engine gaskets, and prying out cabinets. It may not be perfect, but it will get the job done if you do your part.

Try cutting a pizza with a sledge hammer and you will see how versatile the knife is

 

[Cliff Stamp]

If they are sensitive enough for Chris to warn against hard flicks opening the knife you have to wonder.

Reeve has been vague on this, he has never actually what part of the design will fail. The common problem reported in general tends to be dents on the stop pin which induces play. Reeve has a sleeve on his which would mean the user could address this with a simple part replacement.

I wonder how many ancient cultures would see one of us hammering a knife through a log and shake theire heads about the poor moron who does not realize that an axe head should not be shaped like that and could show us how to do it correctly with a properly selected and shaped rock!

Lots of knives are in fact intended to be used for that, shop knives for example in a carpenter's tool chest which are designed for splitting in that manner, Lee Valley sells them for one. Lots of knives are also design to be chopping tools, goloks, bolos, parangs, khukuris, etc., it isn't simply restricted to axes.

Yes there was a time when folding knives did not have locks and their scope of work was therefore limited. As locks became stronger and more secure the knives were able to be used for more tasks. If you look at the knives which have liner locks and people reject, they are typically overbuilt tacticals, thus the complaint is that the nature of the blade is inconsistent with the scope of work of the lock.

Take the knife apart, reassemble then see what it is. On several Sebenzas, this would "reset" the lock so that it travels much less across the tang.

I did this, made no difference.

...you have basically writtent hat the liner lock is such an insecure and unstable lock design that it is almost worthless.

It has its advantages, it opens and closes one handed easier than most locks for example. Most of the more extreme comments come from people like Danbo and USAFSP who say that torquing and spine whacks of any level are abusive. My point is simply from this perspective you limit the scope of work so much you might as well be using a stockman and the lock is pretty much useless because you can induce those types of forces in cutting cardboard and weeds.

If some liner locks fail, and some don't, then perhaps it is not a problem with the Walker design, but rather a problem with execution.

Pretty much, even those who have been strongest in describing their problems have noted they can be done well, Steve and Joe for example have always noted that while some can fail trivially other work well. The biggest problems are :

1) the frequency of problems is high compared to other locks
2) they can pass tests and then fail them suddenly at a later date
3) some of them fail trivially under very low impacts/torques

In regards to the Military, I wrote that two years ago and had not used the knives I have now, as I use knives with higher performance my viewpoint on what is to be expected changes. I check the older reviews periodically and try to keep them up to date, but there are a couple of hundred of them now and from time to time they get contradictory because reference points change.

Specifically, the Military was a lot more secure than the Buck/Strider and to the date of the review was stable under the heaviest work I had done with a folder to date, or pretty much seen anyone promote. Since then my standards have raised, especially in regards to lock torques after applying much heavier ones to various blades and seen what it takes blade wise to be able to resist them.

I can unlock the Military with wrist torque in woods, it takes more force than to split a piece of 1x4" as used in the review, it can even split birch flooring, however as I move to thicker wood the lock will release long before the blade is in danger of breaking, I'll see if I can't get a couple of pictures put up later this evening.

-Cliff

 

[Nathan S]

I would be happy to baton a bit with the framelocks and an Axis lock, hwoever it will take me a week or so before I have the free time.

I've never done any batoning with an axis lock knife, but have done so with two frame lock knives: a Cuda EDC and a Sebenza. I used these knives to split kindling by batoning down on the blade with a chunk of wood. I did this once with the EDC, and repeatedly with the Sebenza.

The EDC held up well, considering its relatively modest cost, but demonstrated slight blade-play afterwards.

The Sebenza, to date, has suffered no ill effect whatsoever to its lock-up.

 

[Scott Dog]

The framelock is the only type I carry (Sebenza). I've had no problems but then again I don't consider myself a hard knife user. If I have a tough job, I'll get appropriate cutting devices. Depending on how you define hard use, is it reasonable to expect any lock to hold versus a fixed blade? To me the framelock seems a very secure locking device and suits my purposes quite well.

 

[Cliff Stamp]

...is it reasonable to expect any lock to hold versus a fixed blade?

It is reasonable to expect the lock to be able to hold up under loads which are not problematic for the blade, otherwise the design is inconsistent.

-Cliff

 

[knifetester]

I can unlock the Military with wrist torque in woods, it takes more force than to split a piece of 1x4" as used in the review, it can even split birch flooring, however as I move to thicker wood the lock will release long before the blade is in danger of breaking, I'll see if I can't get a couple of pictures put up later this evening.

There may be stronger locks around, but I would say Spyderco did a great job on the nested liner lock. You might be able to torque harder if it had a compression lock, but it sounds like it already has a faily broad scope of work already. I would hardly call the Military crippled by its lock design.

1) the frequency of problems is high compared to other locks
2) they can pass tests and then fail them suddenly at a later date
3) some of them fail trivially under very low impacts/torques

Yes, compared to a solid lock back or axis lock a liner lock is probably more prone to failure. However, I still think that proper fit is essential to a liner lock. Moreso than other designs. That is why you here of so few failures with Spyderco and Benchmade liner locks and CRK and Benchmade framelocks. They have fit and finish to be precise and consistent enough to warrant the design.

There are tens of thousands of Sebenza owners on this forum. How many lock failures have been reported?

As lower end knives, like the Kershaw line, Camillus EDC, etc, are fitted with framelocks, it would not have suprised me to if failure reports started to filter in. However, that has not been the case. Reports of framelock failure are virtutally none.

otherwise the design is inconsistent.

Some part has to go first. On a locking folder, I would prefer it be the blade that gave out before the lock. Of course you can make the design more consistent by making the blade less durable. The decrease in cross section should result in higher cutting performance. So perhaps a more consistent design for me would be an axis locking Opinel

On the other hand, slip joint knives will fail under torque and spine whacks all the time. Yet, they are not unsafe to use in careful hands. They simply have a lower scope of work they can be put to. You can cut cardboard, weeds, rope, leather. No, you probably can't split wood with them, but you can't expect to weld a seam with a phillips head screwdriver either.

If I tried to split wood with my Victorinox Rucksak, I would expoect it to fail. That does not mean it is not a good design. It has tons of other uses.

 

[inspira]

Speaking of which, I wonder has anyone had (or heard of) their Opinel lock fail on them?

-- Vince.

 

[STR]

I have a friend that tweaked and tweaked on his Opinel lock until the handle itself broke. I think that is the sign of a good blade and a good lock when the handle gives before they do. It it probably bad that the handle cracked on it but still I guess of the three that is the one you would rather have break over the other two.