Steel Lockbar Inserts - Question

[Petunia D. Feeble]

The only real benefit I can see to the steel insert is the ability to later install a slightly taller one. When a lockbar travels the full width of the tang and no longer provides enough tension to prevent play there's only a couple ways to fix it:

Beefing up the stop pin, either by rotating it so that an unworn portion is making contact or simply installing one of larger diameter. This reduces the amount of rotation in the blade, leaving the tang closer to the top of the lockbar. It may screw up the geometry though, making contact with just the corner of the lockbar rather than the full face.

Replacing the lockbar, which is the entire scale on a framelock. Costly, but is the only way to elongate the lockbar in order to achieve earlier lockup.

Replacing a steel insert. If you can replace the tip of the lockbar, you can achieve earlier lockup by simply installing a taller tip. So regardless of whether the blade tang or the lockbar insert is worn, it can be fixed with a few cents worth of steel and a couple tiny machine screws.

I don't think they're entirely necessary, when you can use carbidized titanium as was mentioned above, but it does allow for cost effective, efficient warranty service.

 

[ChazzyP]

I appreciate your thoughts, ChazzyP!

I was under the impression that CRK heat treated the end of the lockbar higher in order to increase life / reduce lock stick. I was not aware that they did anything beyond that, but I've always been curious about the triangle of silver material in the corner of the lockbar. Perhaps that is the result of the process described above?

The shoulder on my Hati is also present on every Shirogorov 95 I've ever seen. I don't know how much lockbars with steel inserts travel over time (hence this thread), but if they do indeed wear down and travel over through use that shoulder is rather concerning, as it will inevitably prevent further travel and lead to vertical blade play.

I thank you for taking the time to write that post! Good stuff. Hopefully someone with more knowledge of steel insert lockbar behavior will enlighten us below.

I've noticed the lock-bars on at least a couple of my CRKs are somewhat discolored on the interior faces toward the tip and that is where I've assumed that carburizing (heating with a torch to harden) has occurred. That's the process to which I referred.

Exactly my thoughts on that Shiro shoulder. I went back again and looked at my two Shiro liner-locks to be sure, and, again, neither of them has that shoulder. I confess to being relieved at that.

BTW Dmitry13 has a fair number of excellent pictorials reviewing Shiros here at BF. They show a number of models with various upgrades over time and illuminate features with good pics of both assembled and knocked-down knives. I think one of those is where I first noticed that shoulder.

 

[ChazzyP]

I have 2 knives with that shoulder on the lock bar, like Anarchy posted,.....both Benchmades. 790 & 761.
BM then went and installed an adjustable lock pin.....shaped like an octagon.
Not too sure if this was done to compensate for wear or if it is there for adjustment only. I remember watching a vid by that sanctimonious dip stick, apostle, and he trashed it for some reason.
Does anyone know if they came up with this feature to combat what we're discussing??

Great post Chazzzzzy!!
Joe

Thanks for the kind words, Joe.

I had a Benchmade Siebert MPR that had that adjustable, octagonal stop pin. (I didn't recall if it had that shouldered lock-bar, though, so I did a Google image search and found my own pictures from when I posted it for sale--seemed just a little weird.) Anyway, it did have the shoulder and was, like your two knives, a Benchmade Ti frame lock. So that's kind of a BM thing for their frame locks, I guess, though it's not a style of knife that they do often. I imagine it has something to do with being concerned about wear, but seems kinda like butter-boxing to me--put a shoulder on the lock-bar so it can't wear down past a certain point, then put in an adjustable stop-pin to get rid of the lock-rock when the shoulder hits. :confusion:

That was a cool little knife that I bought for a work carry but never pocketed, so I moved it out in a drawer-cleaning sale of knives I liked but not enough to carry or be drawer-queens. It had the weakest detente of any knife I ever owned and you could flick it open by batting your eyelashes at it.

 

[palonej]

Wait a second here Steve!!!!! You batt your eyelashes at your knives??? No more PMs headed your way.......weirdo!!!!
[emoji16][emoji16][emoji16][emoji16][emoji16]
Joe

 

[FlaMtnBkr]

This entire conversation is why I don't like frame locks, and even more so, liner locks.

There are better lock designs that don't have these types of concerns to worry about.

 

[The Aflac Duck]

This entire conversation is why I don't like frame locks, and even more so, liner locks.

There are better lock designs that don't have these types of concerns to worry about.

There are no concerns on my end. I have examples of good and bad frame/liner locks in my collection.

To assume they are all bad is, well...
You know what they say when you assume

 

[ChazzyP]

There are no concerns on my end. I have examples of good and bad frame/liner locks in my collection.

To assume they are all bad is, well...
You know what they say when you assume

No offense to the poster he quoted, but :thumbup: for what Blues said. There are plenty of excellent and terrible versions of all lock types to go around. Most all lock designs have their advantages and short-comings. I like having something of everything--frame locks, liner locks, compression locks, AXIS locks, CBBLs, even back-locks which, while not high on my list of favorites, still have their advantages. I also wouldn't not buy a knife that otherwise interested me just because it had a less-than-favorite lock type.

 

[ChazzyP]

Well, I do love knives, Joe. A little "come hither" glance is not inappropriate....

 

[palonej]

Every lock type can have concerns. To make a blanket statement like that is a bit short sighted. You're also cheating yourself of many fantastic models with these types of locks.
As long as a liner, or frame lock isn't purchased at a gas station your fingers will be safe.
Joe

 

[palonej]

Well, I do love knives, Joe. A little "come hither" glance is not inappropriate....

Don't EVER give one of those glances at my knives sir!!!
[emoji16][emoji16][emoji16][emoji16][emoji16]

 

[ChazzyP]

Not guys' knives, nor guys' wives, Joe, but dealer knives are all free agents, no?

 

[MikeH]

I have had a steel lockbar insert failure.

I pulled my car keys from my pocket and my closed LionSteel SR1 came out with them, falling to my concrete driveway from pocket level. (To be fair, I am 6'8" so pocket level is higher than for most folks.)
when I picked the knife up the blade was flopping around. The steel lock insert had broken in half, leaving nothing to contact the blade.
I still consider this knife model to be built like a tank, and believe that it required an exact angle of impact, breaking the hardened steel. Maybe it was a flaw in the steel, I can't say. They examined it at the LionSteel booth at Blade '16 and promptly replaced the knife with a new SR1.

 

[palonej]

Not guys' knives, nor guys' wives, Joe, but dealer knives are all free agents, no?

I can live with that.......BUT, when they arrive at my house they are no longer free agents!!! Neither are the ones picked up off waivers!!!
Be very careful Steven......you know how those WOPS are.....quite possessive!!!
[emoji51][emoji51][emoji51][emoji51][emoji51]

 

[palonej]

I have had a steel lockbar insert failure.

I pulled my car keys from my pocket and my closed LionSteel SR1 came out with them, falling to my concrete driveway from pocket level. (To be fair, I am 6'8" so pocket level is higher than for most folks.)
when I picked the knife up the blade was flopping around. The steel lock insert had broken in half, leaving nothing to contact the blade.
I still consider this knife model to be built like a tank, and believe that it required an exact angle of impact, breaking the hardened steel. Maybe it was a flaw in the steel, I can't say. They examined it at the LionSteel booth at Blade '16 and promptly replaced the knife with a new SR1.

Hey Mike!!
First off....6' 8"????? That poor knife was in free fall for 10 minutes brother!!!
[emoji51][emoji51][emoji51]
Also......that is no where near 'normal use' my friend!!!
[emoji16][emoji16]
All kidding aside though......great CS by Lionsteel!!
Joe

 

[The Aflac Duck]

I have had a steel lockbar insert failure.

I pulled my car keys from my pocket and my closed LionSteel SR1 came out with them, falling to my concrete driveway from pocket level. (To be fair, I am 6'8" so pocket level is higher than for most folks.)
when I picked the knife up the blade was flopping around. The steel lock insert had broken in half, leaving nothing to contact the blade.
I still consider this knife model to be built like a tank, and believe that it required an exact angle of impact, breaking the hardened steel. Maybe it was a flaw in the steel, I can't say. They examined it at the LionSteel booth at Blade '16 and promptly replaced the knife with a new SR1.

That's absolutely crazy!!!

I've dropped plenty of knives w/ inserts from ladders and scissor lifts 10'-20' up and never had a failure like that! Talk about bad luck

 

[tiguy7]

#1, Titanium Carbide as deposited in a Carbidizing apparatus is quite gritty. Probably not an an ideal surface for a sliding blade tang/leaf spring interface. #2, Titanium above 750 degrees F reacts with everything in sight. If you could heat Ti above 750 F in the presence of a Carbon source, you could Carburize the surface.
When they do this to steel self tapping sheet metal screws, they call it case hardening. These screws have an FeC3 coat 3 mils thick over a less brittle substrate. They cut their own threads but do not snap when torqued.
A process like this would convert the surface of the lock face from elemental Titanium to Titanium Carbide with a hardness >72HRC.

 

[FlaMtnBkr]

I've had multiple frame and liner lock failures on quality knives. And lock rock that can't be fixed is a failure in my book. I've also had a back lock release the blade under pressure. The lock didn't break but is still a failure since my finger got cut pretty bad. And I had an AXIS lock omega spring break. However, I easily made a new one out of 0.025" MIG wire that still works almost a decade later. The lock still worked fine with one broken spring and was an easy fix. I actually prefer something I can fix myself and not have to send the knife off for a few weeks.

Most in this thread are concerned about the longevity of the frame lock and I don't like worrying about that and also have had bad luck and feel it's just not that good of a lock from an engineering standpoint that needs little tweaks to make it work reliably. It also keeps getting more additions to try and increase reliability.

But frame locks are popular so I realize my opinion won't be. I've had more knives than any sane person should own and through use have learned what I like and is reliable, strong, easy/safe to use, and works for me.

But we all like different things for different reasons. I would rather have an AXIS lock that I feel is significantly better than a frame lock in all aspects. When the patent expires soon, I really hope it becomes more popular than the frame lock. I'm sure it won't and many don't share the same feeling.

 

[The Aflac Duck]

I've had multiple frame and liner lock failures on quality knives. And lock rock that can't be fixed is a failure in my book. I've also had a back lock release the blade under pressure. The lock didn't break but is still a failure since my finger got cut pretty bad. And I had an AXIS lock omega spring break. However, I easily made a new one out of 0.025" MIG wire that still works almost a decade later. The lock still worked fine with one broken spring and was an easy fix. I actually prefer something I can fix myself and not have to send the knife off for a few weeks.

Most in this thread are concerned about the longevity of the frame lock and I don't like worrying about that and also have had bad luck and feel it's just not that good of a lock from an engineering standpoint that needs little tweaks to make it work reliably. It also keeps getting more additions to try and increase reliability.

But frame locks are popular so I realize my opinion won't be. I've had more knives than any sane person should own and through use have learned what I like and is reliable, strong, easy/safe to use, and works for me.

But we all like different things for different reasons. I would rather have an AXIS lock that I feel is significantly better than a frame lock in all aspects. When the patent expires soon, I really hope it becomes more popular than the frame lock. I'm sure it won't and many don't share the same feeling.

You're entitled to your opinion, but you aren't the only person who uses their knives around here. Many of us do too, and liner/frame locks work for us.

I've only had problems with said locks on mid-tier knives. High-end linerlocks from André Thorburn or Rockstead will blow you away. As far as framelocks, only CRK does it perfectly IMO:thumbup:

The axis lock is great, but I've had the lock disengage in my hand from forceful cutting, essentially making my hand slide the steel barrel out of place. Never got cut, but I shy away from that lock type.

 

[Anarchy84]

Agree 100%. I collect CRKs, and until recently my collection consisted of nothing else. I recently picked up a couple Shirogorovs, and I love them. I'm just curious about the steel lockbar insert's longevity. Especially since my Shirogorov Hati has a small lip that will prevent the lockbar from traveling after a while. See photo below:



Typically with Ti lock faces the knife will age gracefully (and avoid lock rock) by allowing the lockbar to travel further toward the opposite scale. That way the Ti doesn't wear down too far in one spot. With the Hati pictured above that will be impossible because of that little lip, but perhaps steel will not wear like Ti does?

That's basically what I'm asking. Is this something to be concerned with, or will the insert stop the lockup from wearing down / traveling over as the knife ages?

I appreciate everyone's input and thoughts. We are all passionate about what we like and don't like, and while that is awesome, I don't want this to become a heated comparison of lock types.

We're still looking for someone who may have some more insight into the original question. ^^

 

[ChazzyP]

I appreciate everyone's input and thoughts. We are all passionate about what we like and don't like, and while that is awesome, I don't want this to become a heated comparison of lock types.

We're still looking for someone who may have some more insight into the original question. ^^

Nice post to re-focus the discussion, A84. I hate it when threads devolve into guys touting their favorites and dissing those of others. Joe and I goofing on each other doesn't help either, but we're just silly boys.

#1, Titanium Carbide as deposited in a Carbidizing apparatus is quite gritty. Probably not an an ideal surface for a sliding blade tang/leaf spring interface. #2, Titanium above 750 degrees F reacts with everything in sight. If you could heat Ti above 750 F in the presence of a Carbon source, you could Carburize the surface.
When they do this to steel self tapping sheet metal screws, they call it case hardening. These screws have an FeC3 coat 3 mils thick over a less brittle substrate. They cut their own threads but do not snap when torqued.
A process like this would convert the surface of the lock face from elemental Titanium to Titanium Carbide with a hardness >72HRC.

Thanks, tiguy. What you describe is what I believe CRK does to their lock-bars to avoid the need of steel inserts to achieve greater longevity. Would Titanium Carbide have any less tendency toward lock-stick than elemental Titanium?