frame lock questions

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notos&w

Joined
Jul 17, 2002
Messages
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in a earlier thread i asked about the various types of locks and was told the framelock is, in general, the strongest and least likely to close on your hand.
i understand the reason the for it not closing on your hand (squeezing tighter makes it less likely to open) but cant figure out exactly what makes it stronger than a linerlock. is it that the framelock is thicker? as far as i know, a framelock and linerlock work the same; the framelock essentially being a linerlock w/o the scales.
am i missing something?
 
The frame lock is way thicker, it's as thick as the handle itself, half the handle that is!

James
 
Yes, frame locks are generally thicker, but not always. The stronger locking has more to due with the fact that your hand presses against the lock, thus helping to hold it in place. A liner lock is on held in place by the bend in the locking bar, which can theoretically move back to the side under pressure.

This is theory though. The quality of the design and manufacturing probably have more to due with the lock's reliability than the type of lock itself. I prefer frame locks, but have many liner locks that are superbly strong.
 
Well, that is pretty much it. The "squeezing" is one of the primary advantages of the framelock.

One other significant advantage over a liner lock is that there is no "trap" between the liner and the scale material to trap crud, skin, grit, etc.

When Chris Reeve coined the name "Integral Lock", I presume he was referring to a lock integral with the scale. A new take on the Walker Lock.

Physically though, it is the same principal - bend a piece of steel or titanium and when you take the blade out of the way, voila, you get the liner/frame secured against the blade tang.
 
Originally posted by Buzzbait
Yes, frame locks are generally thicker, but not always. The stronger locking has more to due with the fact that your hand presses against the lock, thus helping to hold it in place.
Click to expand...

In principle this is a very good idea but I have found that with some tip-down knives you end up squeezing the pocket clip (you would have to squeeze REALLY hard to squash the clip and get to the locking bar on my Mad Maxx)...

RL
 
Hmmm... I hadn't considered that. Both my Sebenza and Camillus EDC have finger coils at the locking bar, so your index finger naturally grips the lock with both side and vertical pressure. I'm suprised that Darrel omitted something to facilitate side pressure on the bars of his Mad Maxxes.
 
Framelock knives always have some sort of scallop milled out of them so you can actually move the lock and open/close the knife. Ideally you'd like the material at the scallop to be about .070" in thickness. That gives you plenty of strength but relieves the lockbar enough so that you can move it. Consider that a typical liner lock has liners that are .040-.060" in thickness. There are many other factors possible but these are probably safe averages.
 
You should also consider the so called third gen. locks, like the Benchmade Axis, Rekat Rolling Lock (now in limbo), SOG Arc-lock ,Cold Steel Ultra Lock.

I personally like the BM Axis because
1. your finger doesn't cross the blades path to close it.
2. the lock pulls the blade close in last 10 degree of travel. Meaning the blade won't stay open even when accidently opened a bit.
3. the strenght of the lock, there is a thread that compared the Seb, pinaccle (BM750) and the BM710 Axis, and what can I say but read it yourself.
4. Even my wife knows how to unlock and are un-afriad of it, she is really scared of the liner and frame locks closing on her finger!

There are also some other lock systems out there and if not listed then someone else will surely chime in.
 
Frame locks use the same principle but have a few improvements. Your grip does reinforce the lock like everyone said already, but theres also more strength in the lock alone. The thickness of the tab prevents it from bowing/flexing. Stress that could compress that tab on a liner lock so that it bends or slips, isn't going to effect a frame lock. At least it would take alot more stress to cause problems if the lock is designed right. Thats really only an issue in extreme situations though.
 
What kind of lock is the one used on Gerber's Paul knife? It always seemed solid and the least likely of any I've had to accidentally disengage.
 
I really don't beleive the grip reinforces the lock theory. The amount of force it would take to push the lock bar over would be more than the flesh on your hand would hold. Just grab your fingure like it was a knife and wiggle it. You really think your hand will help hold the lock bar? Not me.
 
I believe the strength -- better, the reliability -- of a framelock has less to do with your hand squeezing the lock and more to do with it protecting it. However your hand may shift around the handle, it still guards the flat locking bar from opening away from the tang. In a liner lock, theoretically, if your grip shifts, you might push the liner out from behind the tang, because your hand was prevented by the handle slab from covering the flat of the locking bar.

Both my Sebenza and Camillus EDC have finger coils at the locking bar, so your index finger naturally grips the lock with both side and vertical pressure.
Click to expand...
Buzzbait, I think that's why Chris Reeve is so adamantly against tip-down carry on the Sebenza, he doesn't want a clip in the way of holding the lock.

However, on both my CUDA Maxx and my DDR custom Maxx dagger, also 5.5", the edge of my undex finger does rest against the locking bar when the knife is open.

* ****** **** ****** *

Burke2, the Paul lock is proprietary, and the whole point behind the knife, and the whole problem with it: it's a button lock and opening mechanism and pivot all in one, and it takes very precise machining to get it right. This drove up the cost and made QC very important. A big company could do it but they would have to commit resources they might prefer to use elsewhere. Of course, the actual Paul knife also used a classic, clean design, which added a lot to its appeal, besides just having such a high-tech lock.

One of the nice points about all framelocks is the simplicity of the design. Sure, precision manufacture and the best materials add a lot to the finished product, but it's much more straight-forward than all the finicky little parts and complex holes and grooves in the axis/arc/ultra locks or the questions about liner thickness or handle slab materials on liner-lock knives.
 
Originally posted by notos&w
in a earlier thread i asked about the various types of locks and was told the framelock is, in general, the strongest and least likely to close on your hand.
Click to expand...

Regarding strength, whoever told you the framelock is the strongest format was pretty much guessing, so take that advice with a large grain of salt. A well done framelock is amazingly strong, but so is, say, a well-done axis lock. With these lock types, just normal failure of the main lock bar (the frame leaf and the locking pin, respectively) may not be what we're looking at. We're looking at shearing through the handle frame (axis) or the stop pin breaking (axis or framelock) or the frame leaf moving way to the far side under pressure (framelock). I've maintained all long, once you get to locks this strong, we really don't know what's stronger than what due to lack of head-to-head destructive testing, and it depends on the particular quality of construction anyway.

Regarding "least likely to close on your hand", again, both axis and framelock have proven to be astoundingly reliable. There are at least theoretical failure modes for each, though in real life they don't seem to show up.

Joe
 
I think Joe said it. Once you get to this level of "ultimate destructive failure", shouldn't you really be considering the use of a fixed blade??
 
Originally posted by Esav Benyamin

Burke2, the Paul lock is proprietary, and the whole point behind the knife, and the whole problem with it:
Click to expand...

I guess that means there's no generic name for it? It's a nice piece of work. I've had mine for about 20 years now, and it seems as good as when it was new.
 
When the question of lock strength or reliability comes up, someone will often comment that framelocks are susceptible to torque failure. I have a Camillus EDC, and it is difficult for me to see how this could happen. Maybe if the blade was stuck in something, I twisted the handle in a direction counter to the lock, and my hand slipped, it could somehow release the lock. It doesn't seem very likely though.

Can someone clarify the point about framelocks and torque failure?
 
Though it does not firectly deal with the issue of lock strength, one additional benefit of the frame lock over the liner lock is that in actual field use the frame lock does not get dirt, mud, fat, blood, flesh and other knife gingering matter beteween the handle slab and the lock bar. Lock backs and liner locks both suffer from having sentitive areas that can foul with debris and render the mechanism inoperative. Yet another benefit of the full tang fixed blade.
 
The Axis lock is not fool/fail proof. The lock can be accidently disengaged when you move your thumb from "the thumb on the top of the blade grip" to a hammer grip - it happened to me and that is why I believe the frame/integral lock to be better.
 
db :

[grip reinforces the lock]

You really think your hand will help hold the lock bar? Not me.
Click to expand...

The limit of hand strength in this manner (very close tight grip) is several hundred pounds of force. Yes it depends on the individual, but in all cases it will be a factor, in some not very significant, in others very much so.

As for causing it to release, if the knife is stuck in an object, and you twist or rotate it, you can induce the lock bar to move and come out of contact with the back of the blade. It doesn't take much force to do this either, just consider how much it takes for you to release it with yout finger.

-Cliff
 
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