2 Chinooks & a Manix failed a "spine-whack"?

I have read this hole thread and I see very little that anyone should feel guilty about or apologize for. If someones true feelings are that they have trouble believing something they have read, they have every right to express that. One thing I've learned in this life; anything is possible. The fact of the matter is it is just a hard story to swallow for most of the guys that have had one of these knives in their hands. Alls I can say is it must have been one heck of a whack to defeat the lock on one of these beasts.
 
Esav, STR,

Yep it did take one HECK of a whack to make the lock "bounce" loose. Much more than I think would generally be encountered in use. I decided to smack them pretty hard just to see how much it would take, if they would fail at all, etc. Like I said, these "tests" were far from scientific, as such I have no idea why the Endura held while the Manix didn't, maybe the lock varies slightly from one to the other, it could be anything. None of the folders were damaged aside from cosmetically (marks on the spine, etc.)
And if anyone doubts that my Manix fails under the these conditions and such, pay shipping and test it for yourself and return when done.
 
What is the test suposed to accomplish in the first place? How would one encounter these conditions in real life application? a sneaky MBC technique maybe? Maybe I'm missing out training to use the edge :confused:
 
You never know what odd problem is going to end up giving a bad lock. Years back someone found problems with a large lockback from another company. The lock seemed way too beefy to fail an easy spine whack, but sure enough, other people on the forums skeptically re-tried the test and they kept failing. The problem ended up being that the lock spring wasn't anchored properly in the handle. So, merely having a big lock spring that fits snugly into its notch isn't enough -- a lock is more than just the little pieces that engage.

No problem with high reporting his experience. Spyderco gets to look at them and see what's up. And the rest of us get to go back to the garage and try a few whacks just to make sure things are sound, so we're sure no odd problem such as outlined above is occurring.. I'm sure at this point that High understands that if a relatively new guy with very few posts takes a knife that lots of people have tested without a hint of problem, and finds a lock problem, people will be a little skeptical. If that same guy finds three problems with three knives, they'll be incredulous. No offense to you, high, it's a natural reaction. Hell, Cliff couldn't get his to fail, and you nailed three of 'em?!?! A little time will tell what's up.
 
Michael Cook said:
What is the test suposed to accomplish in the first place? How would one encounter these conditions in real life application? a sneaky MBC technique maybe? Maybe I'm missing out training to use the edge :confused:
Click to expand...

A true ninja wouldn't have to use the edge. A ninja chop with the spine, and it's lights out.

Seriously, the spine whack is a perfectly reasonable test of basic lock geometry. I tend to use a light whippy snap, which is a slightly tougher test than the real-life condition of getting your knife stuck in a material, then yanking it out and hitting the spine on the uncontrolled withdrawal. Don't roll your eyes, more than a few people have posted about having done this in real life, including a few whose locks failed. Plain and simple, a light whippy spinewhack duplicates some real world cases ... case closed on that.

The really hard hammer-like spine whacks become harder to justify. I know a guy who does it to simulate a defensive encounter, where someone hits the back of the spine with a stick or whatever. You can also imagine a hard snapcut gone awry, which hits ... a wall, a belt buckle, etc. Fine if you believe it, but I generally don't do this type of spinewhack. Ironically, the light whippy snap is more prone to cause failure than a hammer-like spinewhack anyway ... it's how fast the energy gets dumped into the lock that causes the little bounce, often a slower but harder blow won't be a problem.

Joe
 
high said:
in hindsight rather than cause such an upset i should have sent the knives in without posting my spine whacking results.truth is i got caught up in all this lock testing that is so often mentioned on the forums. it was never my intention to bad talk spyderco period.
Click to expand...


You really don't need to apologize for this. I'm sure you understand though alot of folks disbelief that the locks failed on those particular knives. To my understanding these weren't "light taps" or even what I would call moderate hits to the spine on a table, they were full force slams. Seeing as how the lockback geometry is what it is, and the locks didn't "physically" fail (as in break) I'm thinking it does have something to do with the mass of the lockbar + very strong and rapid shock "bouncing the lockbar" a bit at the moment of impact, giving the blade just enough room to slip past that tooth on the lockbar.
 
High,

You are a true gentleman! In my rush to disprove what I thought was another attempt at Spyderco bashing, I trampled on you with my serious lack of tact. For that, I am sorry. You did nothing wrong by posting the results of your spine-whack test, and I should have been more genuine and helping, and a little less sarcastic and skeptical. You seem to be a very good Spyderco customer (who has experienced an unfortunate run of bad luck recently).

All in all, I'm glad that you recieved the help you needed from Spyderco (as I knew you would). As you can see, this is the type of man Sal is. This is another reason I jump so eagerly to defend him and his products. I have yet to meet another person/company with as much integrity as Sal Glesser/Spyderco knives. I could have taken a lesson from him and been much more tactful in the way I brought this topic to his attention and assisted you.

High, I hope you will accept my most sincere apology. I would also like to offer something to you to make up for the mess I created. If your Manix is found to be in good working order by Spyderco, and you are uneasy about using it due to the fact that it failed your spine-whack, I will send you my Manix (which has passed every spine-whack test I've thrown at it), free of charge (including shipping). You have my word on that. Simply post a message on this thread, and I will get in touch with you. :)

Sincerely,
3Guardsmen

P.S.


mike_mck2,

Thank you for coming to High's defense. Your post was spot on!
 
First off, Joe, I very much enjoy reading your posts (have for years) and sincerely appreciate the advice and dedication you selflessly give to the knife community. :thumbup:

The question I wanted to ask was: How did the Manix do in your tests (spine-whack in particular, as I consider you the father of that method of lock testing)? Thank you!

Best wishes,
3Guardsmen
 
imho the spine whack is a great tool to determine if the knife locks correctly BUT ya dont have to whack it into next week, i gently tap the blade against my palm/the carpet on the floor to determine if it locks up right, if ya put on gloves and go to town on 1 well heck i could probably make a extrema ratio folder fail, its just not neccesary to do it that hard imho.

as far as is it possible to have 3 fail, probably so i have had 2 spydies with lock probs (ie lum tanto folder and a millie) myself, which spydie fixed FWIW, but am sure there are some spydies with bad locks floating around in the world, of all models. not that spydies are known for lock probs but lemons are made by all manufacturers no matter how carefull they are and how much QC they have, just happens imho.
 
hi all, first of all thanks 3guardsmen for the apology and kind words. you didn't create a mess. we are all passionate about our love of knives or we wouldn't be here. i look foward to reading this forum every day if possible and that is why i support it with my membership. it is a well of information. sifu1a is correct i didnt spine tap i spine whacked. is it a fair test , i dont know. i noticed that on the chinook with the combo edge the lock release takes much more pressure to unlock . the other two take less pressure. maybe a spinewhack does make the lock bounce out of lock position. i might doubt the lock on my knife but not the company as i will always love spyderco.if spyderco's testing reveals nothing wrong then that is good enough for me. so for now lets just hang loose until spyderco does their thing. high
 
Thank you for being so understanding! I look forward to many more informative discussions with you, here on these great forums. :)

Sincerely,
3Guardsmen
 
Joe Talmadge said:
The really hard hammer-like spine whacks become harder to justify.
Click to expand...

Some knives are intended for back cuts, knives with sharpened swedges or dagger blades for example, it is hard to argue these should not take loads on the spine. Or in general consider any fighting folder which will fold if it takes a rap on the blade, is this really the desired behavior.

It also isn't just simply impacts on the spine but other activities which can cause similar loading, a very hard stab which isn't perfectly perpendicular (in both the way you load it, the vector of the knife, and the resulting non-movement of the target) will cause the lock to experience a very high spine load.

Ritter has also really raised the bar as well by promoting his Grip for batoning. It is simply a case of relative performance. If he can get a knife out there that can do it then everything else has to either match it or settle with being inferior. I started doing this type of work recently simply because I want to know how locks compare to the performance he promotes.

-Cliff
 
I agree with Joe. It is hard to justify hard repeated spine whacks that constitute gross abuse of the knife. I speak for the general buying public. It is another story entirely when someone like you Cliff is asked to do so by the maker. That is a horse of a different color.

From my point of view I have people like you and Sal and Lynn Thompson as well as others to test the knives so that when I get them I can be relatively secure in my faith that it is a good product that can be trusted for what it was intended to do. A light tap or maybe even a real world use heavier one as well as maybe even some other tests are justified and even expected to a large extent to make the user feel better about it and to help build more trust and get to know the knife but beyond that is plainly enough to void any and all warranty coverage plain and simple. It is not something that the general public needs to be doing IMO. Otherwise why do we need you?
 
Mike wrote:

"If Sal, the very person who makes these knives, can manage to consider the possibility that they failed..."

It more likely reveals a good business man who quickly gives the customer the benefit of the doubt.

Sal has demonstrated remarkable interpersonal skills on this forum.

More importantly, he makes the most robust folding knives I have ever encountered.
Good quality, good price, built stout.
I consider my Chinook II the best folder I have ever examined.
I have no, read that as zero, loyalty to Spyderco or Sal.
I wouldn't even recognize the man if I saw him on the street.
I know his knives, though.

With all respect, I think these spine-whack people have had a few too many whacks themselves.
 
I had similar issue with my Chinook II but I have fixed it in a very simple way.

but firstable I didn't need to even spinewhack very hard, just did in with the right speed, the lock started to bounce and after few times disengaged completly. Here's the link to short movie (sorry for poor quality).

but since the Chinook and Manix have regulation of lock spring tension (second big torx screw, near the main pivot) I just tightened the screw, and its all right now. I guess one could still unlock the knife, but he would have to spinewhack very hard, with all available power. Im not going to to this. Check the screws in your knives.
 
lukaszki said:
I had similar issue with my Chinook II ...
Click to expand...

The method names really need to be changed, the "spine whack" as origionally promosed by A. T. Barr and done by Joe is very different than where it went with regards to level of impacts, Steve Harvey probably set the upper limit and this is really a different test both it what is does to the lock and what it is intended to check.

There are four basic types, the very light tap on the back of the hand, the fast whippy snap Joe uses, the heavier impacts which involve more arm movement to accelerate the knife and a tight grip and finally the really heavy spine impacts, batoning and the like which Harvey origionally did for tactical folders and Ritter recently started for survivial folders.

All of these get lumped together under the same term which is kind of misleading, it is like saying "I was cutting some wood with my XXX and it broke." when you were actually batoning it through a heavy knot. Technically true, but send the wrong image.

In regards to the Chinook / Manix, one of the problems with larger knives is the inertia. I can do the above impacts as the movie demonstrated on a $2 lockback "made in taiwan", even harder than illustrated with no problems. It however it very light and thus the impact energies which load the lock are also very small even if you snap the knife very hard.

-Cliff
 
But does the rapid-fire style of spine-whack in that video really simulate anything at all? Sure, it's not that hard, but the lock is only disengaging because of the repeated blows which the above poster says cause the lock to bounce out of engagement.

Spine-whacks that have time between them could simulate real-worl situations in my mind, but that kind of rapid-fire smacking is representative of exactly nothing, in my book.

And I'm saying this as someone who does spine-whack his knives. Of course, I don't try to beat out a rhythm with them like that.
 
Spyderco began spine whacking its production folders in 1981. We were
heavily criticized by manufacturers in a number of countries but we felt
then, and do now, a manufacturer is obligated to extend their best effort to
make their locks as reliabily safe as is possible. We believe Spyderco has been instrumental in helping to improve lock reliability in production knives.

We advocate that every customer do a light spine whack of maybe 5 pounds of pressure before purchasing a knife. A lot of knives are far too sharp to
take a chance on an unreliable lock.

I don't believe any manufacturer would make a knife that would intentionally be unsafe. We have found that slight changes in angle or length or spring strength affects the geometry and consequently the reliability in the the lock.

I would recommend that before you use any locking folder that you test them and then test them periodically. A light tap is not going to hurt the knife, but a pile of lint somewhere in the lock would be a nice thing to know.

If the lock fails and it is not clogged up with debris, or has not been abused, then send it back to the dealer or manufacturer. I am sure they would want to know if there is a problem and would be pleased that no one was accidentally hurt.

Building a safe knife is the manufacturer's responsibility. But using a
safe knife is the customer's responsibility. Cleaning the knife, sharpening
the knife, periodically checking the lock, regular lubrication, these are
all responsibilities of the knife user. While I have not toured Mick's
factory, I think I can safely say that every Stryder is spine whacked at
least once in the manufacturing process, as is every Spyderco.

Manufacturers love responsible users. It makes everybody's life easier. If
you guys are really into this "I can jump higher than you" game, come up
with a set of requirements, invite each manufacturer to produce a model to
those requirements. Come up with a set of agreed on tests that are as
objective as possible and have a "race". To realistically compare knives
like the Manix and the Stryder is unrealistic. Like a 4-wheeler racing a
sports car, the outcome depends on whether they are racing on a racetrack or through the countryside. Every manufacturer is capable of designing and
building anything they want. The results benefit everyone.

A "standard" method of "spine-tapping" for lock reliability that anyone can use and understand is needed. Cliff? Joe?

sal
 
ThinkOfTheChildren said:
But does the rapid-fire style of spine-whack in that video really simulate anything at all?
Click to expand...

You could violently jackhammer stab someone with a similar frequency which could easily induce significant spine loads. You could also baton with similar strikes, even much heavier, generally I don't baton that fast for a number of reasons, none of which are concerned with the lock.

I would be curious if the jarring works both ways, if you chop into something really hard with the edge and then pull back and the spine sees an impact, how much of an effect did the chop have on the stability of the knife in regards to the following spine impact.

The frequency though is a valid point, aside from the speed and power it is also something which should be mentioned to clarify exact what is being done. I don't think for example that the spine snaps Barr proposed were intended to be done at such a high rate.

-Cliff
 
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