Lockbar inserts...improvement or potential problems?

[EChoil]

(I do not yet own a folder with a lockbar insert. Full disclosure.)

I was looking at my ZT 561 the other day, thinking about the addition of a lockbar insert to the newer ones. Then I ended up posting a few comments in various threads about the inserts in general, and it got me thinking...

How many people will really end up benefitting from having frame lock lockbar inserts? Is it really an "improvement" alteration of a frame lock?
​

Assuming the reason for inserts to be lock wear:

First, as an average folder user it's hard to imagine the day coming when I've worn my lock to the extent of rendering the knife useless. I suppose it could happen but I don't foresee it. I know a few hard users will however.

Next, how many of these companies are still going to be around in 10-20 years with the replacement insert for your model when it does wear out? Are these inserts suddenly going to be flying off the shelves in 5 or 10 years? Are companies finding the knives are wearing down that fast already?

What compounds it is they're only available on the finer knives which are supposed to last forever to begin with.

Assuming the reason for lock inserts is to avoid lock stick:

If someone owns and uses a knife they have obviously accepted what lock stick may be present. Is it worth adding another screw and a floating piece to a key stress point on the knife? To me it seems like just one more screw to loosen and one more part to either loosen or fall off eventually.

And being one of the likely stress points on the knife, why would one saw it off and make it a screw on piece vs. retaining solid Ti or stainless structure?

Finally, and please read this, I know there are some frequent users who will wear their knives and a replacement insert will be quite convenient for them...and for those who just can't tolerate the least feel of lock stick in a good knife it may be beneficial.​

But does it really benefit that many people at the expense of so altering that critical area on a folder? Currently I'm more comfortable with that portion of the knife remaining solid of structure. Someone please educate me here.

 

[The Aflac Duck]

It's fairly obvious that titanium is softer than steel. Why have a lockbar that is softer than the blade itself?
Not only does it help prevent wear and stick, it helps prevent lockrock from forming as well. Lockrock has nothing to due with lockup percentage, I have Ti framelocks that are at 30% lockup or less and have lockrock from wear.

It's the same reason why some manufacturers carbidize their lock faces.

 

[rycen]

Is it necessary? No. What it does do is make repairing a problem should it arise,less costly to the manufacture.

 

[Misanthropia]

In regards to them potentially falling out due to a screw loosening, most are press fit into place as well and are very difficult to remove even after they have been unscrewed.

 

[amg137]

While I'm sure it'd take many years of wear to render a framelock truly useless, it's very easy to develop lock rock with an untreated lock face. My 0561 developed moderate lock rock in roughly 8 months, and I don't even carry it every day. Luckily ZT fixed it up and replaced the locking side with one that had an insert and it's been fantastic ever since.

It's worth noting - the appeal of the insert (for me) is not replaceability. The insert itself will be much more resistant to wear than the titanium, meaning you shouldn't need to swap it out. Having the option to replace it someday is just icing on the cake.

 

[Insipid Moniker]

It seems to be primarily a feature on higher end production knives, which are almost exclusively sold to very picky people like us. I somewhat suspect that it's origin is as a cost-saving measure for the manufacturer in case of replacement more than a feature for the end user. I could be wrong, of course.

 

[EChoil]

While I'm sure it'd take many years of wear to render a framelock truly useless, it's very easy to develop lock rock with an untreated lock face. My 0561 developed moderate lock rock in roughly 8 months, and I don't even carry it every day. Luckily ZT fixed it up and replaced the locking side with one that had an insert and it's been fantastic ever since.

It's worth noting - the appeal of the insert (for me) is not replaceability. The insert itself will be much more resistant to wear than the titanium, meaning you shouldn't need to swap it out. Having the option to replace it someday is just icing on the cake.

Noted. Interesting point of view---the insert is the solution to it wearing in the first place, the idea being to AVOID ever having to replace it.

I haven't run into lock rock that much in frame locks so I hadn't considered that it would cure that too.

 

[EChoil]

In regards to them potentially falling out due to a screw loosening, most are press fit into place as well and are very difficult to remove even after they have been unscrewed.

OK. I thought most were attached with screws. So they aren't user-replaceable anyway....has to be done at the factory.

 

[EChoil]

It's fairly obvious that titanium is softer than steel. Why have a lockbar that is softer than the blade itself?

Right. But....in the average circumstance, will it really wear out so fast that it's worth compromising the structure of a titanium lock bar by cutting it, at the most stressed part of the knife, and replacing it with a pin-on separate part?

That's my real question. Maybe it is. I don't know.

 

[EChoil]

Is it necessary? No. What it does do is make repairing a problem should it arise,less costly to the manufacture.

You and Insipid Moniker point out the manufacturer's side...another point I hadn't considered. But again, not necessarily an alteration to benefit the consumer.

 

[PURPLEDC]

(I do not yet own a folder with a lockbar insert. Full disclosure.)

I was looking at my ZT 561 the other day, thinking about the addition of a lockbar insert to the newer ones. Then I ended up posting a few comments in various threads about the inserts in general, and it got me thinking...

How many people will really end up benefitting from having frame lock lockbar inserts? Is it really an "improvement" alteration of a frame lock?
​

Assuming the reason for inserts to be lock wear:

First, as an average folder user it's hard to imagine the day coming when I've worn my lock to the extent of rendering the knife useless. I suppose it could happen but I don't foresee it. I know a few hard users will however.

Next, how many of these companies are still going to be around in 10-20 years with the replacement insert for your model when it does wear out? Are these inserts suddenly going to be flying off the shelves in 5 or 10 years? Are companies finding the knives are wearing down that fast already?

What compounds it is they're only available on the finer knives which are supposed to last forever to begin with.

Assuming the reason for lock inserts is to avoid lock stick:

If someone owns and uses a knife they have obviously accepted what lock stick may be present. Is it worth adding another screw and a floating piece to the most stressed part of the knife? To me it seems like just one more screw to loosen and one more part to either loosen or fall off eventually.

And being one of the highest stress points on the knife, why would one saw it off and make it a screw on piece vs. retaining solid Ti or stainless structure?

Finally, and please read this, I know there are some frequent users who will wear their knives and a replacement insert will be quite convenient for them...and for those who just can't tolerate the least feel of lock stick in a good knife it may be beneficial.​

But does it really benefit that many people at the expense of so altering that critical area on a folder? Currently I'm more comfortable with that portion of the knife remaining solid of structure. Someone please educate me here.

IMHO a properly built frame lock does not need a lockbar insert to perform properly for the life of the knife. Even so i like having them. And I have experienced no ill effects of having one. I have never had a screw come loose and in many cases the lockbar insert is pressure fit so tight that its not going to fall out even if the screw does. Either way loctite is your friend. I also disagree that it is the highest stress point of the knife. I think these points are the stop pin, the pivot and the edge. The only time the lock really sees any incredible amounts of stress is during abuse tests and even in the case of flipper where the weight of the blade puts pressure on the lock when opening the brunt of that force is taken by the stop pin, handle and then the recoil energy which has been significantly reduced goes into the lock and even that is further dampened by the fact your hand and skin is not completely rigid and acts as a shock absorber for much of that stored energy.

 

[EChoil]

It seems to be primarily a feature on higher end production knives, which are almost exclusively sold to very picky people like us. I somewhat suspect that it's origin is as a cost-saving measure for the manufacturer in case of replacement more than a feature for the end user. I could be wrong, of course.

The other original question---are that many of these knives really wearing out that fast; do they have that short of a lifetime?

 

[crom]

I have a frame lock with the insert, not fond of the idea that if I ever did need to replace it, that I could possibly screw those tiny threads up on reassembly. My ti frame locks seem to have settled at a point where lockup is solid and isn't progressing, I have no reason to believe they won't be serviceable 10 or more years from now. As another poster pointed out; what if inserts aren't even available in 10-15 years?

 

[The Aflac Duck]

I have a frame lock with the insert, not fond of the idea that if I ever did need to replace it, that I could possibly screw those tiny threads up on reassembly. My ti frame locks seem to have settled at a point where lockup is solid and isn't progressing, I have no reason to believe they won't be serviceable 10 or more years from now. As another poster pointed out; what if inserts aren't even available in 10-15 years?

Can't say I've had the same experience. I have 3 framelocks that have full Ti lockbars and they all have developed lockrock despite having early lockup. This was in under a year for all of them. I have 3 other framelocks, 2 with inserts and 1 with a carbidized lockface, and they lockup solid after much more use than the others have.

 

[The_Knife_Man]

I used my zt 0561 till it had rock lock. You know opening packages, breaking down cardboard, tuna can, wood, ect.
Eventually sent it in for rock lock; had an insert installed at zt`s discretion.
Back to perfect.

So in long I'd say it's improvement.

 

[1AbominAble1]

It may be that it's possibly easier to produce than a standard Ti frame lock. Upon assembly the worker can put the knife together, adjust insert to the proper place, tighten it down, and call it a day. With a standard frame lock there may be much more taking it apart and fitting the blade tang and lock to get a proper lock up that falls within their percentage of acceptable. If the employee messes up the frame lock he trashes the whole side unless it can be used on another knife that has a long tang but if he grinds the insert too far I doubt that they'd bother trying to save that inexpensive part for another knife- use new one and move on.

I think that it'd be the same for lock up issues for warranty work. It's a much smaller and cheaper part than a whole new 3D machined titanium locking side of the knife.

I doubt that most of the improvements that we see are for the customer but are more than likely for ease of assembly and cost savings.

I've used and abused CRK's for years and have never developed any lock rock, in fact the lock up hasn't changed on any of them. I really don't think that the insert is a necessary item if the knife is made right but I do think it's a great feature that is a huge selling point on paper.


Aren't we all looking for an excuse to buy the next knife anyway

 

[The_Knife_Man]

So in other words it's a clever money saving technique. Saving production cost of roughly $200 per knife with an adjustable insert instead of a hand fitting.
If that's the case; that's a heck of a bargain.

 

[EChoil]

PurpleDC it won't let me quote-post you but you're right. I should have said "key" rather than "highest." I'll revise that. And thanks for the POV.

 

[EChoil]

I have a frame lock with the insert, not fond of the idea that if I ever did need to replace it, that I could possibly screw those tiny threads up on reassembly. My ti frame locks seem to have settled at a point where lockup is solid and isn't progressing, I have no reason to believe they won't be serviceable 10 or more years from now. As another poster pointed out; what if inserts aren't even available in 10-15 years?

Yeah it sounds like the 'user replaceable' hook of this is going up in smoke....

 

[kniferbro]

I think the point of the steel insert is to reduce wear. You basically have a steel frame lock where you want steel, and the weight saving of Ti for the rest. Replaceability is secondary. The inserts may not be available in 15 years but neither will full Ti locking sides. All things the same, and excluding the possibility of replacement, the inserts will last longer than plain Ti, treated or not.

As far as user serviceability, they are press fitted (at least in ZT's case) but I have removed and reinstalled them countless times (when tuning lockbars) with no ill effects.

Also, the inserts (again at least in ZT's case) aren't "movable" to set the lock up. They have one fitted position and are ground to fit just like a Ti lock interface. ZT doesn't scoot the insert up until it makes contact with the blade tang then tightens it down at that position. That would make for an extremely weak lock.