Why Do Seki Models Have Lock Rock??!!

[electro-static]

It has to do with the back spacer. Replacing it with a more rigid titanium one minimized mine.

[Tristan_david2001]

All lockbacks will have some movement. It's part of the design. I have Seki lockbacks using the same geometry and design now over 30 years old and still going strong. The knives haven't changed IMO going by my latest Endura in M4.

They are what they are. Buy them or not. I keep on buying new ones and I have been happy with them. Other people apparently not so.

I have yet to see any chopped off fingers from Seki locks so if anyone here has proof please give us a link to some evidence.

Yep! Wise words here too!

Have any of you posting in this thread had a lock failure with one of these knives? A hint of lock rock doesn't mean the knife is dangerous or the lock is going to fail. Can someone tell me how a tiny bit of lock rock is going to make the lock fail?

As The Mastiff said, the Seki lock backs have been like this since the start. Here we all are still buying them. Why? Because there's no actual issue with them.

A few years ago Spyderco spent a lot of time (and I assume money) to make the Native 5 lock as good as they could. I tested Native 5 LWs last night. Tonight I tested some G10 models and one with fluted Ti scales and one with fluted cf scales, all with steel back spacers. Guess what? If I push hard enough even these have a tiny bit of lock rock. About the same as the Seki models I tested. Native 5s are made in Golden. Yet they still have a tiny bit of lock rock. Because it's just nature of the beast.

So put away your torches and pitchforks and either buy them or not. I can't speak for Spyderco but I bet these knives are the same next month. Someone will bring lock rock up again and we'll go through this same exercise all over again

Not true I’ve experienced many of lockbacks without a hint of wiggle in either direction. It is not inherent part of the lock back design. And I think most people here aren’t saying spydercos lockbacks are unsafe or unreliable or affect performance, but that’s it’s a manufacturing feat that many people expect at spyderco’s price points. Personally I can’t complain, a little wiggle in the lock isn’t enough for me to not use a design I love that is executed nearly perfect in every way

[vivi]

It has to do with the back spacer. Replacing it with a more rigid titanium one minimized mine.

I have had a lot of Spydercos with steel backspacers & lock rock. Chiefs, C95's, etc.

[Sharp Guy]

Not true I’ve experienced many of lockbacks without a hint of wiggle in either direction. It is not inherent part of the lock back design. And I think most people here aren’t saying spydercos lockbacks are unsafe or unreliable or affect performance, but that’s it’s a manufacturing feat that many people expect at spyderco’s price points. Personally I can’t complain, a little wiggle in the lock isn’t enough for me to not use a design I love that is executed nearly perfect in every way

Yeah I thought that most of mine didn't have any lock rock either. It's there. You're just not pushing hard enough. If you don't feel it push harder

People already complain about the price of Spyderco knives. Imagine the complaining when/if Spyderco has to tighten up the specs even more

I don't know why I chime in on threads like these. Have at it. I'm out!

[Tristan_david2001]

i have held lockbacks without rock sharpguy, believe it or not. It’s not inherent to the design. Is it one of the harder locks out there to manufacture with consistent completely tight lockup and good action? Probably. But it’s not impossible. Like I said I’m not one who complains about it, I believe the quality of spydercos products are generally worth their price points.

[Doc Dan]

This is almost disheartening because I've badly wanted to try the K390 steel which so many people rave about. I guess I will have to wait until/if they ever produce an American model with the infamous K390 steel.

Infamous? In what way does K390 have a bad reputation?

I do think the Golden knives have better tolerances, as do the Taiwanese knives. Perhaps a lockback from one of those factories?

K390 does not have a bad reputation. Infamous meaning "widely known and accepted". I can use a different word or phrase to describe the steel though - K390: "Highly regarded, excellent, top notch, fantastic, one of a kind." Hopefully Spyderco will release another American model in the future with this steel because I refuse to pay these inflated eBay prices which some collectors have the audacity to charge when a model is a limited run.

I understand what you meant, but the word infamous means criminal, widely understood to be bad or immoral, and that sort of thing. "Hitler was infamous for his treatment of the Jews." The "In" prefix is a negation, so infamous is the opposite of famous. Another such word is inglorious, the opposite of glorious.

You mean famous, reputable, esteemed, or something of the sort.

K390 certainly is highly respected and esteemed. It is highly regarded and it is one of my favorite steels.

[Sharp Guy]

i have held lockbacks without rock sharpguy, believe it or not. It’s not inherent to the design. Is it one of the harder locks out there to manufacture with consistent completely tight lockup and good action? Probably. But it’s not impossible. Like I said I’m not one who complains about it, I believe the quality of spydercos products are generally worth their price points.

You have to do more than just hold a knife to induce lock rock

Look, I always thought all my Native 5s were solid without any lock rock. I still think they're rock solid because the teeny bit of lock rock I can induce by pushing the blade straight down hard into a block of wood is a ridiculous thing to complain about. All the Seki models I've tested in the same manner are about the same. I actually think my Calys have more lock rock and I wouldn't complain about them and I'm about as OCD as they come. Sure there might be some Seki knives out there with an excessive amount of rock. From testing my own knives this is not the norm and maybe they should go back to Spyderco for them to have a look

Read about the Native 5 and it's lock here

https://www.spyderco.com/catalog/details/C41G5/663

[Tristan_david2001]

Good grief.
I’ve tested* the lockup of lockbacks before that didn’t have any movement, so it’s not an inherent thing that a lockback must have. That’s all I was saying.. I know the vast majority of spydercos have it though but it is generally within acceptable range. But making Rock-less lockbacks is far from impossible

[Ramonade]

Well, if even the words of the guy who designed and manufactured them for decades is not to be trusted, it is sure this discussion will never result in a mutual understanding

[Tristan_david2001]

A mutual understanding on a social media forum isn’t very crucial to me, but it is a shame for being associated as a liar for sharing my experience with mid lock backs and how they can achieve rock solidity, even some spydercos I’ve owned. I guess one who hasn’t experienced it won’t believe. While overall I have no complaints about spyderco’s qc, I don’t knock at when people say they wish most spyderco lockbacks were generally rockfree when other companies can & are doing it at similar prices

[The Mastiff]

Yeah I thought that most of mine didn't have any lock rock either. It's there. You're just not pushing hard enough. If you don't feel it push harder

Yep. That is my experience with them. I have examples from most manufacturers somewhere here in boxes but I always go back to Enduras.

People already complain about the price of Spyderco knives. Imagine the complaining when/if Spyderco has to tighten up the specs even more

I'm one. Sal has stated a few times that if he has to build knives to specs of Chris Reeve 's knives they would cost what one of those does. There is no way around that. Changing a lock design even slightly is no little thing and the hours and costs add up which always comes back to the consumers. I'd go through some of the steps involved but that is too much typing for me.

I don't know why I chime in on threads like these. Have at it. I'm out!

We have this same thread every few years. I always tell myself that this will be the last time I respond but then the next time happens and I find myself reaching for the submit button again. :)

[electro-static]

It has to do with the back spacer. Replacing it with a more rigid titanium one minimized mine.

I have had a lot of Spydercos with steel backspacers & lock rock. Chiefs, C95's, etc.

Every Native 5 LW I have received has had zero lock rock that I could detect. The metal back spacer on my endura 4 lw doesn’t outright eliminate it but it does reduce it heavily for me.


I think it’s possible for seki lock backs to have zero lock-rock but there would need to be a fundamental change to their construction to eliminate it, perhaps to the point where the model number would change (Endura 5 LW, stretch 3 LW, ect…)

[vivi]

It has to do with the back spacer. Replacing it with a more rigid titanium one minimized mine.

I have had a lot of Spydercos with steel backspacers & lock rock. Chiefs, C95's, etc.

Every Native 5 LW I have received has had zero lock rock that I could detect. The metal back spacer on my endura 4 lw doesn’t outright eliminate it but it does reduce it heavily for me.


I think it’s possible for seki lock backs to have zero lock-rock but there would need to be a fundamental change to their construction to eliminate it, perhaps to the point where the model number would change (Endura 5 LW, stretch 3 LW, ect…)

key words in bold

It's easier to detect it on longer knives like the Chief I'd imagine.

I believe Enduras have plastic backspacers, unless you have a g10 or stainless steel scaled model. I know they had to add a pin to reinforce the lockbar spring on the Police LW.

[Wartstein]

..

...
The bottom line is, as some have stated outside of myself, there shouldn't be any blade play in these knives which is not only concerning but dangerous in the long run. ......

I am still waiting for any proof or example that a Seki backlock with slight or a tad more than slight lock rock (and because of that lock rock) is "dangerous in the long run"

Again: I have been using Seki backlocks extensively for quite a long time - really beat on most of them - flick them open all the time - and so on: Not the slightest sign that any of those got "unsafe and dangerous" resp. was unsafe from the get go due to "lock rock".

Also, no account of a such on that forum that I personally read (unlike I did with comp.locks and linerlocks).

This is not blindly defending backlocks, I am truly interested in what you actually mean and how you came to that conclusion. I just don´t see the complaints about "failing Seki backlocks due to their lock rock".

Just the opposite: I can recall both Sal and Eric saying, that they like large folders like the Police (Seki...) to have a backlock, because this lock is particularly safe and strong (I can search for those quotes if you want me too).

[Wartstein]

Yes, I guess this is the kind of lock rock guys are talking about and the kind of my Seki folders have too: With most I have to either press them really hard on a surface or grab the handle tight and force the blade upwards in a pinch grip to induce slight movement.
My Stretch XL LW for example even then feels almost rock solid, while older Enduras have slightly more.

EXCATLY and like you say and I say:
- This (the only slight amount of it) is also the reason why the "lock rock" that folks are complaining about does not bother me personally at all.
It is a none issue for me, and not a safety issue by any means anyway for anyone.
.......

Correct. You just GUESS. Don’t you guys think you are a little too arrogant ? No need to tell others what they experienced. We are not hallucinating…. I guess. In reality me (and others like me) experienced a very perceptible lock rock. The kind of lock rock that is easily perceptible with your senses when you grab the tip of the blade and you push it up and down with just a small amount of force. You can see it and you can feel it with ease. No need to push hard in a piece of wood. I hope I was clear this time. I had hundreds of Seki made models over the years(not to mention people I know and friends and others on this forum) and many of us had the same experience. I am not saying that all Seki models are the same. Some come with this lock rock from the factory and some develop it in time and some might just be totally free of lock rock(which I doubt). And yes, when you cut with your folder and feel the blade moving, you have the right to be annoyed and to doubt the reliability of your lock. And yes, I saw Seki lockbacks failing and I am not saying this is the norm. You trust and favor them ?! Good for you, enjoy. I love most of my Seki models but I only wish they implement a stronger lockback, that’s it. You will never hear me complaining about my Chaparrals.

Hey Marius, I think you got me wrong - and my apologies should my post not have been worded carefully enough.

I did not mean to imply by any means that I don´t take guys seriously who don´t like the "Seki lock rock"!
I actually literally stated in some posts that I respect and even understand that, despite I personally feel differently (though again: It does not really matter to me, but gun to the head I´d also say lock rock FREE is better all other things equal!)

I was just honestly of the opinion and thus seconded what "Sharp guy" said, that this slight up and down movement of the blade actually IS what you are all taking about, cause I did not read about much more severe examples so far.

And I thought it could further the understanding of people reading this thread, cause for the longest time I myself did think my Seki backlocks had NO lock rock at all, till I realized that actually that rather slight movement is meant (and most or even all of then have THAT when I really try to induce it).

[Bolster]

...this slight up and down movement of the blade actually IS what you are all taking about...

It would be great if we could quantify this. What is "slight"?

It's difficult to tell if the disagreement between the two sides is: (1) actual different amounts of rock; or (2) the different amounts of tolerance that different owners have for relatively uniform amounts of rock across all Spyderco lock backs. (This section option is difficult for me to believe because I see large variance in rock across the many Spyderco lock backs that live in my sock drawer, but leave that aside for now.)

Most of my Spyderco lock backs have (what I would call) very slight, or virtually no, or sometimes just no, up/down blade movement. Ie, unnoticeable levels of it--no complaints, a non-issue. Several (in particular my Mokis) have/had (what I would call) obvious movement, enough that I didn't want to use them.

So I don't entirely disagree with those who say "it's a non-issue." I partly agree with that statement, for many/most of my lock backs, particularly the Golden lock backs. But it's an issue for some of my lock-backs.

It would be nice to be able to remove the subjective part of this discussion, and replace it with actual measurements. Maybe the insults would stop flying back and forth if we had actual measurements.

[RustyIron]

Well, if even the words of the guy who designed and manufactured them for decades is not to be trusted, it is sure this discussion will never result in a mutual understanding

Bwahahaha! Y'know, those are the truest words of this whole thread.

It must be hard being the renowned leader of a respected company, and reading posts about how you're doing it all wrong. My first response might be, "Why don't you go out and buy some steel and some plastic and make yourself a better knife. Until then STFU and quit bothering me." But that's why I'm not the renowned leader of a respected company.

That's not to say that some good ideas are not generated from The Forum. Even a blind pig finds an acorn once in a while. Mabye the name of the forum should be the Blind Pig Society.

Oink.

[Bolster]

^ I think it's more complicated than saying "Whatever is, is right." (Apologies to Alexander Pope.) If that were the case, there'd be no CQI.

First, nobody has said Sal is "doing it all wrong." I think most of us greatly admire how well Sal does everything he does and has done. The forum is the voice of aficionados, and Spyderco uses it from time to time to adjust course.

Second, Sal is not making the knives himself. He has expressed many times, over the years, how he has to work with the existing subcontractors at whatever level they're at.

Third, Spyderco already has a fix. It's called a stop pin, and they've implemented it in several knives already.

If rock weren't a concern, if it were truly a non-issue, why would Spyderco implement the stop pin in the first place?

[electro-static]

It has to do with the back spacer. Replacing it with a more rigid titanium one minimized mine.

I have had a lot of Spydercos with steel backspacers & lock rock. Chiefs, C95's, etc.

Every Native 5 LW I have received has had zero lock rock that I could detect. The metal back spacer on my endura 4 lw doesn’t outright eliminate it but it does reduce it heavily for me.


I think it’s possible for seki lock backs to have zero lock-rock but there would need to be a fundamental change to their construction to eliminate it, perhaps to the point where the model number would change (Endura 5 LW, stretch 3 LW, ect…)

key words in bold

It's easier to detect it on longer knives like the Chief I'd imagine.

I believe Enduras have plastic backspacers, unless you have a g10 or stainless steel scaled model. I know they had to add a pin to reinforce the lockbar spring on the Police LW.

I replaced the backspacer on my endura 4 with a flytanium titanium one. The original backspacer was likely FRN and had molded pins with some flashing on it. I think a move to actual metal pins may help.

I played around with my N5 LW Lc200N and couldn’t find any “lock rock” until I gripped it very tight at a weird angle, I then adjusted my hand and it went away. Turns out it was just my palm meat pressing the backlock loosening it. I had to work pretty hard to “find” what turned out not to be lock rock. beat this knife through wood too so it’s not like I babied it either.

I don’t own a native chief so I can’t speak for lock rock on it. From the looks of it the back spacer in the N5LW may actually be a part of the linerless scales rather than a third piece sandwitched between steel liners like on the endura.

It could be partially a size thing too, I noticed less lock rock on my delica which is the same length as the N5.

Seki’s spydercos are my favorite knives from them so it isn’t really a deal killer for me, they are reasonably priced knives with comfy handles, thin geometries, and high performance steels that other makers charge an exhorbant premium for if they offer them at all.

[electro-static]

Infamous meaning "widely known and accepted".

No.

My apologies. It does mean generally regarded as bad, unacceptable, notorious. I used it in the term of being widely known. It's famous K390 since that is the word you're looking for.

This post was supposed to receive good feedback, which some definitely have, not turn into a firestorm of keyboard warriors defending their opinions and loving to start arguments because they haven't grown up.

I do appreciate all who've commented with their constructive criticism and honest feedback and experience.

The bottom line is, as some have stated outside of myself, there shouldn't be any blade play in these knives which is not only concerning but dangerous in the long run. I exhort anyone who hasn't already, to dip their toe into the world of custom knives. Go out and spend a lot on a custom piece (do your research on makers though). You won't be disappointed. Please see the tight tolerances, flawless grinds, and attention to detail of these amazing products and I'd like to see blade play or lock rock of any kind be acceptable or "not concerning" in that kind of market. That clientele wouldn't have it. [Example: Ford or McLaren; Kia or Koenigsegg]

The production market such as Spyderco, Benchmade, Hogue, Microtech, Pro-Tech, etc. probably makes up the biggest profit margin in the knife industry. However, if custom knife makers had thousands of forums to expose their repetitive flaws (the kind that production companies all carry over) the industry would take a huge loss in income from these makers. Just one custom knife most times can be the same price as 10-20 production knives. For all those who say custom isn't worth it, you have not idea, because, you don't know what you don't know.

Custom makers have a reputation to maintain and they won't let things like lock rock, blade play, bad grinds, poor heat treatment and many other things ruin their products or sully their name. That's why there are so many stellar custom makers making and selling some of the highest quality knives on the market. We live in a golden age of knifemaking and it's exciting to see what will happen even in the next 10-20 years!

I like my custom fixed blades I own two and have two more on order they are very close to the price of high end productions , but it’s hard to see something complicated like a folding knife ever being affordable enough to use and break from small shop, as precision machining is expensive as is the time of a master craftsman. I can’t really see a sub $500-1000 folder being profitable for a small custom shop.