Fixing Lock Rock in Seki FRN lockbacks

[DavidNM]

I am curious to know if the lock rock remained after new scales and backspacers were installed? Has anyone swapped out the scales an backspacers on a Delica or Dragonfly? Was the lock rock eliminated or reduced?

I own two native 5’s from golden none of them have any lock rock whatsoever. But that could just specific to that model.

I have a Lil’ Native and it doesn’t have any lock rock that I can detect so maybe the Native/Lil Native design lends itself to eliminating lock rock?

[James Y]

Well, the Golden back locks for the Native 5, the Native Chief, and probably the whole back lock Native family were re-engineered, and have a deeper lock notch than the Seki back lock design (the latter was, if I'm not mistaken, originally an AL Mar design back in the late '70s or early '80s or so).

Jim

[DavidNM]

Well, the Golden back locks for the Native 5, the Native Chief, and probably the whole back lock Native family were re-engineered, and have a deeper lock notch than the Seki back lock design (the latter was, if I'm not mistaken, originally an AL Mar design back in the late '70s or early '80s or so).

Jim

I was not aware of that. Out of curiosity I checked my Dragonfly for lock rock and I had a very difficult time feeling or seeing any and I was pushing pretty hard on the handle. This is a non-issue for me but it is interesting to know that the Native line of folders lock mechanism was re-engineered.

[James Y]

Well, the Golden back locks for the Native 5, the Native Chief, and probably the whole back lock Native family were re-engineered, and have a deeper lock notch than the Seki back lock design (the latter was, if I'm not mistaken, originally an AL Mar design back in the late '70s or early '80s or so).

Jim

I was not aware of that. Out of curiosity I checked my Dragonfly for lock rock and I had a very difficult time feeling or seeing any and I was pushing pretty hard on the handle. This is a non-issue for me but it is interesting to know that the Native line of folders lock mechanism was re-engineered.

Many years ago, I wanted an original Golden-made Native, but every one I handled in shops had blade play/lock rock. So I never bought one. This was maybe back in the late '90s or beginning of 2K. The current re-engineered Golden back lock is wonderful. I'm sure there are people who have experienced lock rock in their re-engineered Golden back locks, but all 3 of mine have been rock solid.

IIRC, it was the late AL Mar who originally introduced Sal to the Seki makers to manufacture Sal's first Spyderco knife designs. And that AL Mar also gave permission to Spyderco to use his design variation of the mid/back lock.

Jim

[Wartstein]

I’m not sure what is meant by lock rock here. Are people using the knife hard and noticing movement in the lock while it’s being used, or are people generating lock rock by moving the blade up and down by hand? I...

I am not 100% certain sure either, since I figure that different people could mean a slightly different experience when it comes to perceiving "lock rock"?

To me it is something that can be provoked in any backlock Spydie I had except the Chaparral when I press the blade down harder on a surface.
This causes the lockbar to move a bit. Not an issue at all to me personally in most backlock Spydies, cause in actual use it is barely or not at all noticeable.

If I had a model where this kind of movement would be a lot more, it would bother me though.

What lockrock is NOT (imo): When the blade gets a bit looser cause one accidentally activates the lockbar to a small degree by really squeezing the handle. This can happen (more) with no- boye-dent Spydies, and to me is another (and more annoying) issue than "lock rock" ads I define it for me.

[electro-static]

The criticism of those who criticize Seki lock rock is always the same: "You are demanding the perfection of absolute rigidity, you need to lower your standards, the knife is perfectly safe and useable with rock, it doesn't bother me, therefore it should not bother you."

I think that's a straw-man argument. I can't speak for everyone, but I'm not asking for a back lock with zero movement (though it would be nice, and is the case for the Chaparral). I am willing to accept a little lock rock. I have many Spydercos with a little lock rock and they are very satisfactory. (I also have many Spyderco backlocks with none, at least under normal conditions--Golden models as you might guess.) But a good number of my Seki models...I'd guess a third...came new with so much rock it bothered me enough to stop buying certain models that I really liked otherwise.

While some of you are recommending "Just live with it," I'd encourage Spyderco's subcontrators to reduce the amount of rock, since we have seen it done successfully. Yes, I'd pay more for higher QC standards, or tighter fitment, or an improved back spacer, or a stop pin. There is a stop pin in the Chap and it is still an affordable knife in FRN.

This forum is filled with fanboys and I am definitely one. But I don't think fanboyism means we can't voice dissatisfaction if done logically, politely, with evidence of the problem, and with an eye to possible solutions. I'm not hostile to Spyderco just because I'm pointing to something bothersome that can be improved. Just the opposite.

I'm a fanboy too. I would also prefer if the tolerances of the Seki knives were as good as the Taichung or Golden knives, but they aren't.
It'd be great if that could be improved. I really like a lot of the Seki knives and have a preference for back locks as I prefer folding knives to stay closed when I want them to stay closed.. I still like the products which are made in Seki and will continue to buy them even if no tolerance changes are made.

However, it's easy for me, some bozo on the interwebs, to say "increase your tolerances", but actually doing so is surely an expensive proposition. I'm sure that would require lots of machinery and other capital expenditures. Lots of money to spend only to make marginally "better" versions of what they already make. There's no additional profit to make there with that investment. It's probably more rational to expect the tolerances to get better over longer periods of time as machinery needs to be replaced.

So, I really don't think that Seki's lower tolerances is a problem which actually needs to be solved.

I do have back locks with lock rock from other manufacturers. Actually, every non-Spyderco back lock I own (honestly not a lot, so small sample size) has some noticeable lock rock. I suspect that back locks without lock rock are more of an exception than a rule (barring designs which include stop pins).

I'd sure like to see more Taichung back locks too given that the Chaparral is such a perfect thing.

I would expect that more use the powerlock instead would "solve" rock lock, however, it has a higher part count than a traditional back lock. I would like to see it get used again.

honestly the cost associated with “increasing tolerances” isn’t worth it. the Seki K390 line let us try super duper steels in fantastic designs for a fraction the cost of a custom. I would say keeping the price point is vastly more important than lock rock. Spyderco makes excellent cutting tools, not pocket jewelry.

To your point, I will try taking apart an endura a d re-assembling it again to see if it improves the lock rock as you say, and if the Ti backspacer is just a red herring.

So I tightened up the T6 screws on my other endura’s handle and found that it seemed to reduce the lock rock. So at this point I can’t say if the new spacer helped or the reassembly did. I did the same for my stretch 2, and it seemed to help but not as much.

Note: While lock is improved by tightening the screws, it isn’t to the same extent as the improvement with the Ti backspacer.

[RugerNurse]

My dragonfly has more rock than my salt 2 but I only use my dragonfly for around the house light stuff like opening packages, cutting string, etc. the salt 2 is pretty good but it’s the first one I remember having lock rock. The delicas I’ve had in the past didn’t have anything I remember. Maybe it’s linerless models that make it worse?
I’ve bought and sold a number of native 5 models and none of them had any rock.

[prndltech]

My dragonfly has more rock than my salt 2 but I only use my dragonfly for around the house light stuff like opening packages, cutting string, etc. the salt 2 is pretty good but it’s the first one I remember having lock rock. The delicas I’ve had in the past didn’t have anything I remember. Maybe it’s linerless models that make it worse?
I’ve bought and sold a number of native 5 models and none of them had any rock.

Ahhh… the dragonfly. One of my favorite knives ever. I can tell you they are extremely tough and that you’ll probably hurt yourself before the knife. Not that I know from personal experience or anything…

[Urkilnmesmalls]

I have a stretch 2xl salt that the lock rock is very noticeable and I would send it back if I hadn’t dyed it already. That said, I have been using it as a short machete against blackberry vines and it’s not unlocked on me or anything. It is annoying when whittling and things like that but it’s useable.

[Ryder]

I have two copies of the Dragonfly in K390. One has a little rock to it and the trademark side of the blade isn’t finished as good as the signature side. My second copy doesn’t have any but an almost imperceptible rock, almost not there and both sides of the blade are equally finished. They are both working blades so I don’t really notice or care.

So you that live near a brick and mortar dealer are lucky to be able to check several copies of a model as you choose.

[Paul Ardbeg]

Just got the Endura 4 wharncliffe in K390. First thing I checked was the backlock. When I hold the blade and firmly press down it has the tiniest bit of lock rock. With normal use you will never notice it, even when pushing down hard so a non issues for me.

[Ramonade]

Many years ago, I wanted an original Golden-made Native, but every one I handled in shops had blade play/lock rock. So I never bought one. This was maybe back in the late '90s or beginning of 2K. The current re-engineered Golden back lock is wonderful. I'm sure there are people who have experienced lock rock in their re-engineered Golden back locks, but all 3 of mine have been rock solid.

IIRC, it was the late AL Mar who originally introduced Sal to the Seki makers to manufacture Sal's first Spyderco knife designs. And that AL Mar also gave permission to Spyderco to use his design variation of the mid/back lock.

Jim

I concurr. I've had more than 20 Native 5s in my hands over the past few years and only one of them had perceptible lock rock when I tried to find it. My Native 1s are different, one is like the N5 and the other is more like an Endura.

Over time it can become more perceptible but the fact that the design makes the lockbar put constant pressure on the blade tang must help ! I've had to regrind the lock interface of my Maxamet N5 and there's still 0 lock rock. A lot of material was removed.

Such an excellent backlock design !

[ejames13]

Interestingly, I just picked up a Salt 2 wharncliffe in LC200n, and it has the best lock up of any Seki knife I've ever owned. Absolute bank vault, and I cannot get it to rock or wiggle at all.

My K390 Delica wharny on the other hand is probably the worst of all. It's not actually the lock though. It rocks at the pivot on nearly every cut I make, with even the slightest pressure.

[yalel]

Its all a matter of production tolerances. If the pin that goes through the lockbar does not get “press-fit” into the scales the slightest space in that connection creates the lock rock. With G10 and FRN handles of several Native 5’s I tested no lock rock was there as these scale materials allow for a super tight fittings of the pin the lock bar pivots on into the scales. When I have lockrock I wrap 2-3 times a thin , small band of plumbers tape around that area of the pin thta goes on both sides into the scales and “problem” fixed. If the lockbar cannot go anywhere , even the slightest bit, the lockbar rock cannot occur. Again it is all about tolerances ( costs) in production.

[Flash]

If the consumer is paying a premium for a product then it’s important to expect premium quality in return.
At Spyderco’s general price points, zero lock-rock is the only acceptable amount of lock rock.

The amount of blade play and uneven grinding my wharncliffe K390 Delica had would suggest it dropped out of a cheap Christmas cracker!

[yalel]

Indeed. As I stated in both my G10 en FRN Native 5 with OEM scales I had NO rocklock. It was only when I installed after-market scales that this occurred.

[elena86]

If the consumer is paying a premium for a product then it’s important to expect premium quality in return.
At Spyderco’s general price points, zero lock-rock is the only acceptable amount of lock rock.

The amount of blade play and uneven grinding my wharncliffe K390 Delica had would suggest it dropped out of a cheap Christmas cracker!

I totally agree. I never understood why Spyderco doesn’t implement tighter tolerances or a different engineering when it comes to the Seki backlocks. Maybe because most buyers seem to embrace the “it doesn’t bother me” slogan every time the lock rock subject is discussed. Well, it’s annoying for quite a few of us when the lockrock is present and this should be enough.

[RyanY]

Its all a matter of production tolerances. If the pin that goes through the lockbar does not get “press-fit” into the scales the slightest space in that connection creates the lock rock. With G10 and FRN handles of several Native 5’s I tested no lock rock was there as these scale materials allow for a super tight fittings of the pin the lock bar pivots on into the scales. When I have lockrock I wrap 2-3 times a thin , small band of plumbers tape around that area of the pin thta goes on both sides into the scales and “problem” fixed. If the lockbar cannot go anywhere , even the slightest bit, the lockbar rock cannot occur. Again it is all about tolerances ( costs) in production.

The plumbers tape is very clever. I may have to try that on my delicas

[SpyderEdgeForever]

1 can lock rock cause someone to lose a finger?
2 can we put aftermarket stop pins in?

[dsvirsky]

1 can lock rock cause someone to lose a finger? To the best of my knowledge, no one has ever received so much as a scratch because of lock rock.
2 can we put aftermarket stop pins in? Theoretically possible, at least with knives that have liners. But, I'm reasonably certain you'd have to get it exactly right on the first try.