Let's talk about locks

Discuss Spyderco's products and history.
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sal
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Let's talk about locks

#1

Post by sal »

I would like to have some discussion on locks; types, advantages, disadvantages, reliability, ultimate strength, user friendly, etc.



I would like to (here) develop a "Tech Report" of a sort to try to put establish values on these features.



More on a learning mission, than a race.



I would like to keep it here on this forum (don't want to offend anyone), so please do not make any announcements on other forums about this discussion. It could go nowhere (now here as opposed to no where? the importance of open space?), but it might get honest and often honesty creates friction.



Types: (please add any I miss)



1. Lockbacks

A. rear (eg: Buck 110)

B. mid (eg: Native)

C. front (eg: early Al Mars, Spyderco Rescue)

2. Linerlock

3. Rolling Lock

4. Axis Lock

5. Ultra Lock

6. Arc Lock

7. Frame Lock (Chris Reeve style integral linerlock)

8. Compression Lock

9. Balisong Lock



"Observations" could be thrown in a hat, with sorting done periodically. A general discussion on locks.



What started this line of thought was;



1. We have 3 new locks in R&D and I am on a "truth" mission.



2. We have been breaking knives for a while now. As a result, we've set up a standard and we are trying to build to those standards.



3. We recently broke some of our competitors knives that are promoted as being "tough", "hard" reliable "do anything" pieces. most tested "medium duty" lock strength by our in-house standards (50 - 99 inch/lbs per inch of blade length).



(As a comparison, our Endura, Delica & Calypso FRN models are "Heavy duty" (100+ inche/lbs per inch of blade length.)



So I'm after the real truth as well as opinions, perceptions and experiences.



BTW, heard a great line on one of the forums. Don't remember who said it (sorry).



"They call them fixed blades cuz they aint broke".



sal



Edited by - sal on 6/17/2001 4:06:53 PM
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vampyrewolf
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#2

Post by vampyrewolf »

1. Lockbacks
A. rear (eg: Buck 110)
B. mid (eg: Native)
C. front (eg: early Al Mars, Spyderco Rescue)
2. Linerlock
3. Rolling Lock
4. Axis Lock
5. Ultra Lock
6. Arc Lock
7. Frame Lock
8. Compression Lock
9. Balisong Lock


1a> been around for a long time, old-timers are used to them. I don't like them as much, but they are placed well out of the way. 6/10
1b> easy to close one-handed. Supposed to have the best strenght of type 1. 9/10
1c> same as type 1b isn't it? 9/10
2> best lock for small knives. allows for wear. gets an 9/10.
3> haven't used, haven't seen
4> very easy to open, fun to play with. gets a 6/10.
5> haven't used, haven't seen
6> haven't used, haven't seen
7> this is what's used on the KISS isn't it? if so, usefull in theory, but any pressure and it's closing on your hands. 3/10
8> upside down linerlock, better power? new, unable to rate
9> haven't had time to play with these yet.

10> paratrooper clasp(metal piece holding handles together).
-strong metal, otherwise it bends.
-once loosened up, opens about as fast as my Delica.

We all start with 10 fingers. Those with Spydies have 9 to spare, Still need a thumb. Good thing I still have 8 to spare...
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Carlos
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#3

Post by Carlos »

My lock design priorities.

1. Mechanical simplicity
2. Ease of use, one-handed, opening/closing
3. Reliability
4. Strength
5. Long-Term Wear
6. Ambidexterity


I think the obsession with strength is over-rated -- reliability is more important IMO. The real need for strength comes from those people who mis-use their folders as prybars, hammers, etc., with a specialized need in MBC.

1. Lockbacks: Not too complicated and easy to make reliable, they suffer from two problems. One, the stronger you make the lock, the harder the knife is to open. Two, it is difficult to close one-handed, and some blade shapes (Civilian) make it rather perilous to close one-handed. The Boye-type cut-out is a must have refinement. A mid or front position for the lock-back is essential for easier one-hand closing.

2. Linerlock: This is still my favourite. It is the simplest, a one-piece lock requiring only one liner. It is the easiest to open and close one-handed, whatever the lock strength. Because the simple design hides little understood sophistication, reliability is a problem outside of high-end production folders and custom knives. Even then long-term wear will always be an issue, so even if it tests high for strength and reliability at first, it can not be predicted to stay that way. An excellent design for everday-carry, sub-optimal for MBC/critical missions. It is also more easily adapted to various handle shapes than most others.

3 - 6. I will put the complex mechanical locks in one group. The fundamental theroretical flaw of all such locks is that this more that can go wrong, more parts that require maintainance and repair, and are more vulnerable to fouling from contaminants and are more difficult to clean. All of these locks are so new that their long term reliability is simply unknown. The Rolling lock suffers from its bulk and weight -- there is not yet a thin or elegant folder with a Rolling lock. Aside from their complexity, the only flaw I find with the Axis, Arc, and Ultra locks is their positioning on the handle, which strikes me as vulnerable to acccidental opening during use. Most ranting in favour of these locks, really points to better day-to-day reliability than medium and low quality linerlocks, not better lock strength. Most people don't see the distinction between reliability and strength.

7. Frame locks: By this I assume you mean something like AG Russel's One-hand knife, and not the integral forms of linerlocks and compresson locks. My one experience with a frame lock is that there was a lot of resistance while opening, and it was tricky to close one-handed. Simplicity of design was good, but it needed tuning. Can't comment on long term strength or reliability.

8. Compression lock: I'm still waiting for the Lil' Temperance to try this for myself. Fundamentally, in terms of simplicity, strength, and long term reliability, it is the best concept I've seen. It appears to suffer from some difficulty in one-hand closing, yet is better than a lockback in this.

9. Balisong: The prince of folding knives in utility form. Almost nothing to go wrong, and the tighter you hold it the stronger it is locked. Unfortunately, the martial side of the balisong heritage (and Hollywood misuse) appears to have gotten it legislated into a shadow existence.
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sal
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#4

Post by sal »

Sorry for the confusion. By frame locks, I was referring to the Chris Reeve style. Pat Crawfords "frame locks" are IMO basically lock backs, without the lever. But we can add them to the list, should anyone wish?

I'll correct the 1st post. Carlos, Thanx for bringing it up.

sal
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#5

Post by Joe Talmadge »

Of the properties I feel are important, <b>strength </b> is the one that seems to play to the knife-buying masses the most. But once a certain level of strength is reached, other properties become very important, very quickly.

<b>Reliability </b> has, of course, been an interest of mine for a while. More is always better, and the lock should be rock solid when white knuckled, torqued, spine whacked, etc. It should not be easy to accidently release it, and should not auto-release on its own. In addition, the lock design should be such that it can be consistently mass-produced in a reliable manner. A lock format with many subtleties and nuances -- like the liner lock -- is not a good choice for that reason, IMO. Keep in mind, also, that this is a folder, and under hard use the frame might twist some, that should not effect the lockup!

<b>Action </b> is important. The lock should not just allow a smooth action, but the action should hold the blade firmly in the closed position. If it doesn't, whatever solution you use to hold the blade closed must be reliable! The ball detente mechanism used by many liner locks makers is often executed very poorly.

<b>No play </b> is another important feature. At least one of the newfangled lock formats seems to loosen up and allow some blade play after a little hard use. As the knife is used, parts start to wear, the frame and other parts settle into their break-in positions, the lock if anything should tighten up.

<b>Self-adjusting for wear </b> is the one feature that I feel the liner lock has that its popular predecessor the lockback lacks. Of course, liner locks often have the opposite problem -- they can wear too quickly. But absolutely, as the lock wears, the lock should self-adjust; but it shouldn't wear too quickly.

<b>Ease of unlocking </b> is important. Due to the difficulty of making liner locks reliable, many manufacturers have lowered the angle on the blade tang and lowered the liner beneath the scales. Now it's more reliable, but you have a sticky lock that needs two hands to release. If unlocking isn't simple and easy, and if solving the problems results in reliability problems, you should pick another format.

<b>Resistance to dirt </b> is obviously important. I've had a whole bunch of lockback failures due to pocket lint recently, so much so that I'll only carry lockbacks as clip carry, not in-pocket carry. Your lock format should be as resistant to dirt, lint, etc., as much as possible.

<b>Mechanical simplicity </b> is more theoretically important than actually important, in my mind. The axis lock is more complex than the liner lock and the integral lock, yet is more reliable than both. However, it is true that more complex mechanics will generally be less-reliable ... just don't get too hung up on this if you have something that really is reliable but a tiny bit more complex.

<b>Ambidextrous </b> locks are nice to have. Not a must for me, but nice to have, too. They are very important for lefties, obviously, and for the defensive crowd that likes to carry a knife on either side. I'll trade off ambidextrousness for other features, if I must.


I could go on, believe it or not (!!!), but those are the main points.

Joe

Edited by - Joe Talmadge on 6/17/2001 4:14:04 PM
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#6

Post by Joe Talmadge »

okay, that said...

Lockbacks: Aside from what Carlos said, lockbacks are also pretty susceptible to dirt. They also don't adjust for wear. In addition, they can be easy to unlock through palm pressure. Depending on the shape of someone's hand, they might have more problems with accidently unlocking front, mid, or back locks, so the user might want to try a few knives and see which cause him problems. I find this a good choice for lower-end knives. When executed masterfully, like Steve Mullins Pack River folders, it's an excellent choice all around.

Liner locks: My least fave type, to the point that I consider them unacceptable. The ball detent mechanism is often unreliable, the lock itself is way too often unreliable. I strongly disagree with Carlos statement that "reliability is a problem outside of high-end production folders and custom knives". In fact, some of the highest end production makers and big-reputation custom makers make some very questionable liner locks. The fact is, this format is so astoundingly difficult to make reliable that even some of the very best can't do it consistently. Too many field reports of failure, too many failures in bench testing, too many failures period. There are manufacturers and makers who are better than others, but I see no more reason to take a chance, given the superior lock choices coming out.

Axis: My top choice of lock format. It is reliable, period, in the face of everything you can throw at it, including dirt. It holds the blade securely in the handle when closed. Action is smooth. As executed by Benchmade, this is the one to beat, period. I suggest forgetting hypothetical objections about complexity: Field report and bench-testing wise, it is much more reliable than the less-complex locks. Benchmade has scaled it from beefy hard-users, to inexpensive zytel handled knives, to gents folders. My only complaint might be that axis lock knives can be a little thicker than comparable liner locks and lockbacks.

Rolling lock: theoretically the same as the axis lock, in practice not executed quite as well by REKAT, and more reports of failures.

Ultra lock, Arc lock: Two axis variants. I have no experience with the ultra lock. The arc lock appears very promising, although my sample showed some blade play after use.

Frame lock: Simple, strong, reliable. It has the same susceptibility to torquing that the liner lock has, but if designed properly, the hand will support the lock, so reliability isn't an issue. Still, occasional reports of failure in counter-clockwise torque (for righties), where less hand reinforcement is on the lock, occur. This lock style also puts severe constraints on the design and aesthetics. I like this lock, but the design constraints it imposes get old real quick.

Compression lock: With the exception of ambidextrousness, this lock has potential to deliver strength and reliability and all the other important features, without imposing obnoxious design constraints. It may very well be the best of the bunch -- or the worst <img src="smile.gif" width=15 height=15 align=middle> The fact that it made it past the Stamperizer is a good sign. I'll have to handle one to be sure!

Joe
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Carlos
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#7

Post by Carlos »

Hi Sal,

Thanks for clarifying. It redo #7:

Frame lock: The advantages of the frame lock (integral linerlock) are its potential for greater lock strength and its greater simplicity. With the common linerlock, the strength of the lock rests primarily upon the pins holding the knife together. A frame locks strength is limited by shape and thickness of the lock lever where it joins the scale.

Reliability should be equivalent to a linerlock if implemented correctly. Sebenza fanatics who rant on the concept that you grip the lock closed overlook the issues that this is only true if you hold the knife in one specific way (a grip that I myself rarely use), and that if you are in contact with the lock a twisting motion could disengage the lock while cutting.

The disadvantage of this type lies in ergonomics and limitations on design -- unlike a linerlock which can be adapted to any handle shape.
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#8

Post by J D Wijbenga »

Below are some of my thoughts concerning locks.

1. Lockbacks
In general I think lockbacks are best for the lower end production knives (below+/- $75). A good lockback is dependable and strong but on many you can push the blade slightly upwards into the locking bar. This does not compromise functionality but is unacceptable on an expensive knife. An expensive folder should lock up rock solid with no play. Expensive folders should me more than just functional. I think that a lock back can be made this solid but that it is difficult to do it constantly in a production environment.
A. rear (eg: Buck 110)
The work but are difficult to close with one hand.
B. mid (eg: Native)
The best lockback layout in my experience. It works well and easy.
C. front (eg: early Al Mars, Spyderco Rescue)
Don't know.
2. Linerlock
Best in Gentleman knives. I do not entirely trust them. I have heard to much about them going wrong, though some are better then others. At the moment I carry a Starmate and think its liner lock is secure and save but not rock solid. If I push on the back of the blade when it is open I can bent the spring a bit. This my very well be my last linerlock. The are easy to operate though. I hope to switch to the compression lock soon.
3. Rolling Lock
Don't know.
4. Axis Lock
Solid as long as the springs do not break. On my BM710 they did break, both of them. I think the springs are the biggest weakness of this design. On the plus side it is, besides solid, save, easy to operate, and a joy to play with.
5. Ultra Lock
Don't know.
6. Arc Lock
Don't know.
7. Frame Lock (Chris Reeve style integral linerlock)
Solid and save but on my BM Pinnacle I can push the lock spring, when the knife is open, upwards. This makes it feel a bit cheep although it doesn't effect lock strength.
8. Compression Lock
Not enough experience jet.
9. Balisong Lock
Solid and fun. It like to play with balis. They are the safest folder in existence when open. The only drawbacks are the limited handle configuration possibilities and the law.

IMHO the key to a good lock is good quality control. Most locks work if you make them right. And they all require small tolerances to function safely and smoothly. Most locks that fail do so due to bad materials or bad fit and finish.

Sal, good luck with the new designs and thanks for asking.
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#9

Post by Joe Talmadge »

JD -- Although I've read of an Axis spring failing now and then, it's always one spring that fails, and the other one works as a failsafe just as Benchmade says. I did read one case where one spring broke, but instead of returning the knife the owner continued to use it, and the 2nd spring broke a month later. One case does not a trend make, but the lesson I took away was: in the unlikely event one spring breaks, you've got a few weeks of fail-safe on the other spring, so send the knife in as soon as you can.

Was that you who posted about one spring breaking and then the other breaking a month later? If not, then that's two cases of this happening. How soon after your first broke did your second break?

Joe
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#10

Post by J D Wijbenga »

This is the first time I have reported this happening. I think the second spring broke about two months after the first one went. Getting a BM fixed when you live in Europe is an expensive business so I didn't want to send it back after the first spring broke, after the second one I had little choice.

JD
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#11

Post by Tightwad »

In the company that has repiled so far I can only offer a consumers point of view. So here goes...
Lockbacks.....
A. the buck 110 lockback is well proven and simple.It is a favorite.
B & C both mid an front lockbacks are useful on small to medium size knives.
The "Boye dent" is a much needed improvement on the front / mid locbacks
As to the rolling lock axis lock and all of the other "Types" of lockback I am unable to comment.
What I can say is if the locking back method is solid and reliable then it 's ok with me.
Linerlocks......
Not worth a darn. I have only seen / used one linerlock that merits ownership...The Schrade 125ot
Mustang. It's not even a true linerlock ....it's a slipjoint (another favorite) with a brass linerlock saftey.
To bad they don't make them anymore.
Frame locks....
From my view pont another linerlock and just as un-reliable.
Balisong locks ......
As close as is possible to fixed blade in a folding knife as you can get. I'd guess that why they have
so much trouble with John Law.
Keep in mind that any folding knife will never be as strong as fixed blade. After all if there is a joint
the knife will in time fail to lock or at least will break under duress.
So for my money I'll buy / consider any lockback on the market and will NOT consider / buy any
linerlocks. But again that's just me........
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#12

Post by tique »

1. Lockbacks
A. rear (eg: Buck 110)
B. mid (eg: Native)
C. front (eg: early Al Mars, Spyderco Rescue)
2. Linerlock
3. Rolling Lock
4. Axis Lock
5. Ultra Lock
6. Arc Lock
7. Frame Lock
8. Compression Lock
9. Balisong Lock


1.A. These have stood the test of time as others have said, they are not my personal favorite, and I don’t own a single one. The seem to work very well for the ELU that prefers some of the less expensive cutlery though, so I would not rule them out by any means.

1.B. These are quite similar IMHO to 1.A., but different at the same time. I own a few of them, my Calypso Jr. and my Boye Folder are two that come to mind. They seem to provide a good amount of lock strength, but are still a bit cumbersome to use one handed.

1.C. Don’t have any experience with these to be honest, so comments are minimal. They appear to be similar to the others lockback types though, and more like B than A.

2. Linerlocks are still one of my favorites… I know there are some reported problems with them, but I still trust most of them. I am a little picky as I have had two knives from well respected companies have worthless liner locks, but they also fixed the problem when confronted about it.

3. Rolling Locks suck as far as I can tell. I have had two REKAT’s with them, and got rid of both as quickly as possible. They stick, sometimes don’t engage right, and overall are a pain in my hind end. I also dislike the fact that they are not ambidextrous. I don't know if it is actually the lock or just the execution by REKAT, I was not satisfied with either of their knives that I owned, the fit, finish, and function that I desire were not there, so I doubt I will ever say another good thing about them or purchase one of their products.

4. I really like axis locks. My current EDC is an axis lock, and will continue to be until I get my custom folders that are on order in. They function well, I have never had one fail on me. It appears to be a very strong lock setup, but I do not have the numbers in front of me, and I have been proven wrong on this sort of thing before. The axis does have the problems of too many parts though. There is a lot of stuff that can go wrong and/or break, but I have never experienced it, and reports seem to be quite rare.

5&6 I have no experience with. They appear similar to other formats discussed above, and from what I have heard are not as favorable as an axis lock, but I have no first hand experience.

7. I still also like frame locks. Some are well built, some are not. I think there is sufficient strength for what I use one for in the lock. I know they also have problems similar to liner locks in addition to the fact that they are quite weak at the bend, but I don’t generally put that much stress on a folding knife.

8. Compression locks look really sweet. I played with a couple at BLADE, and I am hoping that I can pick one or two up sometime soon, but I have to wait for the desired models to come out, and I need to save some cash due to upcoming deliveries.

9. I am a fan of the Balisong. I think it is the most reliable folding design that is in production. I have a few, and I have another on order. If/When the Spyderbali is a reality, I am probably going to be among the first in line to get one.

I think that when it comes to locks, one of the best ways to judge what you like is by looking at what you carry. I currently carry a BM 735(axis lock), Spyderco Calypso Jr. lightweight(mid), Boye folder(mid), and a number of fixed blades. As far as the folders I have on order, one is a liner lock, the other is a frame lock. I think the makers do excellent work, and I have total confidence in the product they produce. I have talked to both of them, and they appear to know their stuff when it comes to their lock, and have done a good bit of work to perfect it.
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#13

Post by Sword and Shield »

I have to step in regarding liner locks. My Kershaw Liner Action Tanto is very strong, and I never have given a second thought to the lock failing or even slipping. Opens in a flash, locks tight, flips shut just as fast.

While I understand how some "lower" companies offer weaker knives and locks, pay for quality and that is what you will receive.


Keepin' it real...real sharp, that is.
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#14

Post by Joe Talmadge »

S and S --

You may very well have a perfectly strong and reliable Kershaw there, so for the rest of this reply forget your Kershaw and let's speak more generally. What follows is just my opinion, but it's opinion that's backed up by probably at least an order of magnitude (if not two orders of magnitude) more hands-on testing than the average knife user.

To clarify, in your reply you have focused on the strength of the lock in your Kershaw and of the knife in general ("offer weaker knives and locks&quot<img src="wink.gif" width=15 height=15 align=middle>. No one is questioning the strength of a well-done liner lock; in fact, I personally say that a well-done liner lock is plenty strong. The problem here is reliability. This isn't a hypothetical concern: as I said, over and over again, liner locks have had a disproportionate number of problems in the field, and in testing. Furthermore, you absolutely cannot tell how reliable your liner lock is just by how strong the liner seems, or how solid the lockup <i>feels </i> . Testing is the only way to be sure -- and I say this because I've managed to get some very solid-looking, solid-feeling locks to give.

More importantly, my experience is directly contradictory to your statement, "While I understand how some 'lower' companies offer weaker knives and locks, pay for quality and that is what you will receive." I've found there's only limited correlation between high-quality companies/makers and the reliability of their liner locks. I am decidedly not impressed with the liner locks of Microtech and Emerson, for example, though I believe both companies (especially Microtech, which really does raise the bar) are making a very sound product otherwise. Likewise, there are some very big-name makers whose liner locks used to be very suspect, though a couple of them have improved greatly in recent years -- still, they were already huge names when they were making suspect locks a few years ago. Liner locks are so difficult to consistently get right that even buying from a very high quality manufacturer or maker guarantees you little. That does not mean that some companies are not more successful than others at making reliable liner locks -- Benchmade's liner locks are excellent, and Spyderco better still. But there are some surprising names in the "suspect reliability" column.

I heartily recommend reading the Liner Lock Test FAQ and testing all your locks. Spyderco already does the most important tests in-house during QA, probably one of many factors as to why they are pretty successful with their locks.

Joe
PS Sal, I'm not sure if I'm out of line by directly mentioning other manufacturers, but I needed to do so to illustrate one of my points. My apologies if you're uncomfortable with it, and I'll refrain from doing it again if you let me know.
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#15

Post by Carlos »

I am a fan of the linerlock, but all of this may be moot as I just asessed what's been happening with Spyderco and locks (that I know of), and I think that the linerlock's days at Spyderco may be numbered.

Item #1. Military is being moved to a compression lock,and Mil Jr will have one ab initio.

Item #2. Of several latest releases from Spyderco, two are compression locks (Gunting and Vesuvius), two are lockbacks (Chinook and Ayoob), and only one is a linerlock (Lum Chinese) -- and that one they tried to fit with other locks first (rolling, then lockback).

Item #3. New in-house folders over the next 6 months to 1 year? The Lil' Temperance folders, Meerkat, "Salsa," and ATR. All compression locks except for the Meerkat, which has a new in-house lock.

Item #4. New custom collaborations? Wegner "Lynx" and Janich MBC. Both compression locks.

Item #5. We expect that a few of the present custom collabs with linerlocks to be discontinued this year to make room in the lineup.

I bet that in a year or two there will only be a few linerlock knives from Spyderco, either because their designs require it (Lum Chinese, Cricket) or because of custom maker preference with custom collabs. Alas poor linerlock, we hardly knew ye!

Edited by - Carlos on 7/1/2001 1:27:24 AM
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sal
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#16

Post by sal »

Hi S&S. Welcome to the Spyderco forum.

Hi Joe. I don't mind metnioning other company names on this forum (especially the Tekno). I don't think I would want to do it on BF though.

I think linerlocks will have their place in smaller knives in the future. the built in problems that Joe mentioned are real. Even the Kershaw that is rock solid now, may not be in 3 years. We have done a great deal of R&D on these locks to get where we are, but they can never have a really high ultimate strength because of the direction of the forces when tested.

We recently broke a Buck Strider and Emerson's "#1 hard use knife in the world" (at least that's what it said on the box). Both rated medium duty (over 50 inch/lbs per inch - under 100 inch/lbs per inch) by our standards. For comparison the Calypso jr is heavy duty (over 100 inch/lbs per inch of blade length).

BTW. Pulleeaaze don't repeat this outside of this forum. I'm not trying to cause argument.

The reason reliability is difficult in linerlocks is because of how critical the interface is. Angle, materials, wear and surface finish all affect the interface and all change with time.

sal
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#17

Post by Tightwad »

Hi Sal, At the first of this thread you stated that this was a "learning misson". So with that in mind I
offer this thought....The linerlock seems to be a least favored type of lock with the various "types" of lockbacks getting better press. Your new compression lock (as I see it ) is another simpler type of
lockback that looks to be a strong safe lock. Now to where I'm going with this.... the lum chinese
is a very good well proven old asian utility blade that is still very much favored in the east. It works
for 99.9% of daily chores with great ease. But......It is a liner lock. Before you groan "not again" !
please consider converting the chinese to a compression lock or a front lockback (in the manner of
A.G. Russells' famed "one hand" knife. ) when / if it is ever offered in FRN handle. I've read else
where that FRN has crossed other folk's mind as it has mine. I've used the chinese design years
ago in Asia in a slip joint and liked it then. So this "Type" of lock change might help sales of this
model & cost to the consumer. My point here is that any folding knife made CAN be made in a
lockback of some type. Would I buy a chinese in FRN lockback ....I might but as long as it's a
linerlock I know I won't. As a consumer I stick with what work's for me. I'm sure many others
feel the same way.
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Joined: Fri Sep 24, 2004 10:33 am

#18

Post by Joe Talmadge »

Sal: I think a year or two ago I switched to a similar position on liner locks: a nice option on gents' folders and smaller lighter-use knives, unacceptable on larger, harder-use knives. This was a modification of my somewhat extreme previous position: "unsafe at any speed" <img src="smile.gif" width=15 height=15 align=middle>

Tightwad: I don't look at the compression lock as a lockback variant; it is decidedly a liner lock variant, to my eyes. However, it theoretically solves many liner lock problems, and will hopefully fulfill the original promises of the liner lock. The liner lock is deceptive: on the outside, it looks so simple (just a slit in the liner), but it is actually outrageously difficult to make a good one. In fact, even the added complexity of adding omega springs, milling out handle slots, etc (ala the axis lock) yields a lock that is more consistently reproducible than a "simple" liner lock, because the only problems that need to be solved seem to be spring technology, rather than complex geometry changes. The compression lock, in a very simple and elegant way, promises to solve the most difficult problems the liner lock has. And it solves all of them all at once. Bushing and washer compression, change in tang/liner geometry over time, change in handle geometry under torque or other load.

Joe
Tightwad
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Posts: 255
Joined: Fri Sep 24, 2004 10:33 am

#19

Post by Tightwad »

Hi Joe, As a consumer I can lay no claim to any level of expertise about knife locks at all. My comments
were intended for Sal and the readers (you et. al.) to see how a consumer might view this subject. I'd
have to agree with you 100% about the compression lock. It is a variant of a linerlock differing only
where it engages the blade.... on the back of the blade. Thus as a consumer I'd consider that to be a
"type" of lockback with he exact mechanics of which, for this discussion, is unimportant. The mix
of expert opinions (such as yours) and those of consumers ( such as mine) comprise the information
that Sal was looking for I hope. Consumers tend to lump "type" together as one kind. I feel kinda
special that a person of your level of experience cared to comment on my offering . Thank's
GronK
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Posts: 218
Joined: Fri Sep 24, 2004 10:33 am
Location: Pueblo, Colorado, USA

#20

Post by GronK »

Don't mean to pull this thread off-subject, but would just like to express my appreciation to you, Sal, and your company for continually searching for improvements in an already excellent product line. This came to my attention when I recently received my second "Viele". I've owned the earlier version with serrations for some time and have carried it as a large gent's folder. I decided to try one of the new ones in plain. The improvements you've made are spectacular! They make it the best, by far, of all the liner locks I've tried. Still silky smooth, but solid as a rock!
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