Durability Of Linerlocks

[MANIXWORLD]

Ok,i know linerlocks are not a favorite amongst most of you guys here on the forums,and i myself have to say that i would take a lockback over it any time of day.
There are some knives in my collection that have linerlocks and integrated linerlocks.
How long do linerlocks last before they wear out?
are integrated linerlocks a bit more durable than standard linerlocks?
it might not be the strongest lockmechanism on a knife,but would it last the lifetime of the knife?
integrated linerlocks look alot neater and wellmade on certain knives,than standard linerlocks.
i have seen some linerlock knives that look real poorly made.
any opinions on the subject?

[dete]

I'm not sure what you mean by integrated liner lock,

but the all the CRKT models that I like, their Special Forces models are all liner locks and I don't mind at all since they have the LAWKS lever on it.

Another liner lock that I don't mind is the Cold Steel Ti-lite because of it's extra thickness.

I'm not quite sure why they can't make a knife that as the liner wears down, the blade simply adjusts to it, eventually making the blade open at a less than 180 degrees :)

[David Lowry]

I don't like liner locks period. However Spyderco changed me to a liner lock lover (only on one knife). I will not use a liner lock unless it's on the Spyderco Military. That lock kicks total ass.

I've not tried any other Spyderco liner locks but I may considering the lock that I love on the Military.

As far as how long they last. I would say many years (3-5) depending. If I used a Spyderco Military until the lock was all the way accross the tang I would send it in and see if they could fix it up for me and then use it some more. ;)

In my personal opinion as a person who has tried and used about 30 different liner lock knives the Military is the best ever made.

[yablanowitz]

Yes, the liner lock will last the lifetime of the knife, since the lock no longer working means the knife is worn out. ;)
Everything wears out eventually, backlocks, compression locks and plunger locks included. My old 440V Military has less lock travel than my newest S90V Military. I expect both to last for the rest of my life, but they will wear out someday.

The liner lock is deceptively simple. They are popular on low-end knives because they are cheap and easy to stamp out. Getting them right is another story. Getting any knife lock right takes engineering and manufacturing precision and skill. That costs. Cheap knives have given liner locks a bad reputation.

I always have to laugh at people who hate liner locks and praise framelocks, usually for the wrong reasons. I've only seen one person mention the real advantage of the Reeve-style framelock, which is lockbar rigidity and the dynamics of how and where flex occurs. Once again, the lock has to be done right to work right. Personally, I don't like them. I have several and none has won a permanent place in my pocket. It's the single feature that stops me from buying a Sebenza. Put scales over both sides and I might consider it. Oh, wait...wouldn't that make it a liner lock?

Of course, my whole philosophy on knife locks is rather old-fashioned. To me they are like seatbelts. They might prevent injury in an accident, but driving defensively to prevent an accident works even better. As far as I am concerned, if the lock has to do its job, I haven't done mine.

[raven]

I'm not sure what you mean by integrated liner lock,

I'm not quite sure why they can't make a knife that as the liner wears down, the blade simply adjusts to it, eventually making the blade open at a less than 180 degrees :)


Hey dete, I believe the "frame-lock" is the integrated liner lock he's referring to ;).

There are some liner lock models that are made to adjust to blade/liner lock wear. When new you'll see the liner lock almost at the edge of the blade and over time it will engage more toward the center of the blade.

If you look real close at the area where the blade and lock engage, you'll see that the blade where there is surface contact with the lock, is ground in an arc or at an angle. So over time when the lock wears a little, it moves over and adjusts to the surface to surface engagement without having to much verticle play. Hope this helps some ;). Take Good Care Knifebro and Be Safe Always.

God Bless :)


-raven-

[spydutch]

I may be in the minority, but the linerlock is my most favourite lock.

Back at the old printing factory I was working we were issued with a POS China made linerlock. Opened the darn thing a hundred times a day and the lock never failed on me. No blade play either.

So imagine how secure a nested liner lock a la Military will be.

Man would I like a Paramilitary with that nested liner lock intead of that wobbly compression lock:(

[dete]

Hey dete, I believe the "frame-lock" is the integrated liner lock he's referring to ;).

There are some liner lock models that are made to adjust to blade/liner lock wear. When new you'll see the liner lock almost at the edge of the blade and over time it will engage more toward the center of the blade.

If you look real close at the area where the the blade and lock engage, you'll see that the blade where there is surface contact with the lock, is ground in an arc or at an angle. So over time when the lock wears a little, it moves over and adjsusts to the surface to surface engagement without having to much verticle play. Hope this helps some ;). Take Good Care Knifebro and Be Safe Always.

God Bless :)


-raven-
wow thank you Raven for the detailed response!
makes a lot of sense now.

take care
:)

[Brad S.]

Lock wear and tear and how long it last has two main things to take into consideration.

1. The user
2. The maker

1. The user who constantly flicks the blade open should expect the lock to wear faster. Any lock design. The user who gently opens the blade and allows the lock to engage will have a knife with a very poorly built linerlock last a lifetime!!!

2. The maker has alot to do with this. A properly engineered and built linerlock will last just as long as a lock back IMHO. In fact i would go to the point of saying that long term a linerlock could outlast a lockback. A lockback really cant be peened to account for blade wear, a linerlock can, thus giveing it the possibility of a much longer life.

As a third point mostly focused on a comment by yablanowitz
It's the single feature that stops me from buying a Sebenza. Put scales over both sides and I might consider it. Oh, wait...wouldn't that make it a liner lock?


I struggled with this a while back, trying to figure this out. This was my result.
I feel that a Framelock can remain a framelock even with a scale on the outside as the lock is provideing the strength and or frame of the knife. A linerlock without the scales will not function as a knife, it is simply to weak. A framelock without a frame is not a knife a all. A framelock with scales on it can function without the scales. This is all simple my thoughts and I am always open to thoughts and comments.

[yablanowitz]

So as soon as the liners get thick enough, the knife suddenly becomes a framelock with scales instead of a linerlock. Interesting viewpoint.

I'm not really making fun of you here Tricod. To me, a knife with scales on the outside and a lock with the geometry and construction of a Sebenza would be a linerlock. The layers inside the scales are called liners, and the lockbar is part of the liner, so it is a liner lock, no matter how thick the liners are. If the knife is made without scales on the outside, the outer layer is no longer a liner, since it doesn't line the scale. Therefore it is now a frame, regardless of the thickness of the stock.

What do you expect from someone who considers locks on knives optional?:D

[KaliGman]

I have quite a few Emersons with liner locks, a few Militaries, a green Lum Chinese that I carried a lot, etc. I have worn out exactly one liner lock--on an Emerson Combat Karambit (after years of kinetic openings, waves, etc.--I had one of the first of the production Emerson Combat Karambits). It was repaired under warranty by Emerson. Good quality liner locks can work well. As with any lock, test the lock up every now and again and retire or refurbish those knives that don't lock up correctly and you will be good to go.

[MountainManJim]

I like liner locks. They are quick and easy to use.

But, as a person who buys used (and before that cheap) knives I have ended up with two knives that demonstrate the faults of liner locks.

The first example is a failure due to poor design or manufacturing. To accommodate manufacturing tolerances, the liner lock bar interfaces with an angled surface on the blade (as described by Raven). If the blade is not ground at the right angle or curved like the Sypderco grind, the lock bar will “cam” back to the unlock position and disengage when a closing force is applied to the blade. I have a knife that will close on me with very little force applied to blade. Scary! :eek:

This failure mode illustrates a short coming of the liner lock. There is usually a force on the lock bar that will try to disengage the lock when a closing force is applied to the blade. As far as I can see, the only thing stopping the lock from disengaging is friction. In fact, I have one knife where the manufacturer (CRKT) has apparently bead blasted the surface of the blade to increase the friction and to provide a more “solid” lock-up. Engineers usually try to avoid relying on friction to hold things in place (a little oil can kill the friction force). There is a certain amount of distrust of friction, but in truth it is used in may applications.

I believe other manufacturers concentrate more on geometry of the lock and blade interface. It looks like Sypderco has gone to great lengths to decrease or eliminate this disengaging force on the lock bar through their curved grind on the blade. I think others go for more of a “locking taper” between the lock and blade.

The other example I have is a very used knife where the there is apparently so much wear on the liner lock that the bar travels clear to the opposite side of the handle. There is a lot of vertical play in the blade because of the clearance between the blade and bar. The good news is that the bar wedges between the blade and the handle when a closing force is applied to the blade, so the blade can’t close no matter how much force is applied.

I guess there is one thing I have learned but liner locks … test the lock periodically by trying to close the knife when it is locked up. But, remember to keep those fingers out of harms way.

Oh great, another long post by me :o

Jim