Kershaw Spine Whack Fail

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I don't understand the point of the spine whack test. I don't know a situation where I would need to turn my knife around and beat it on something?
 
Lock could nearly fail spine tapping a wine glass. This is blatant abuse? Please explain.

Yes D Monk, I am narrating the vid.

Spine whack test is odd way to evaluate knife value. Still, it is perplexing how such light shock could disengage safety lock. All it means to me is Spyderco Para is back in the pocket. No spine whacking with that one but the old user Tenacious held up just fine.
 
Honestly though, this horse has been beaten to death. To me it tells nothing. I don't tend to cut with the spine anyway. That would be something though. I'd love to see a video with somebody trying to cut phonebook paper with the spine of a blade, claiming it failed and concluding that the blade is inferior.
That would probably give the same amount of information as this video...
If you want a blade that does not fail spinewhack tests, go get a fixed blade. It will do marvelous in these kind of tests, I can assure you.
 
A slip joint will fail a spine whack test every time and people have been using them for a long time. Just sayin
 
Isn't this just a test of the lock strength? Wouldn't you want to know the strength of various knife locks? Kind of like
car tests when you'll never drive your car that way.
 
Nic S. said:
I don't understand the point of the spine whack test. I don't know a situation where I would need to turn my knife around and beat it on something?
Click to expand...

A lock is a safety feature, ideally you'll never rely on it for anything. That being said, it's still pretty important to know if the safety feature is gonna keep you safe.
 
I'm going to try my Kershaw/ZT knives, just so I know for my self. Pretty sure my RAM will do fine.
 
Nic S. said:
A slip joint will fail a spine whack test every time and people have been using them for a long time. Just sayin
Click to expand...

And if all you want are slip joints that's great, but if I want a knife that locks I want it to stay locked through more than was demonstrated in the video.
 
Wow, it's just amazing how people will defend failure. I got the same kind of response when I posted a thread about my ZT 0200. It will pop open on a spine whack against the palm of my hand that doesn't hurt my hand, so it's obviously not that hard. I mean, the purpose of a lock is to lock, right? Not some of the time, not most of the time, not only under certain conditions but 100% of the time until I purposefully decide to unlock it. Otherwise, why don't we indeed just all go back to slipjoints and rely on no one ever having any kind of accident or doing something inattentive and stupid? To me, this video and my own experience says that Kershaw/ZT needs to work on their linerlock lock face geometry at the least. It's not a problem restricted to Kershaw/ZT, either. I have three Spyderco Resiliences, none of which will withstand a light whack. On the other hand, I have a cheap Schrade linerlock whose locking bar is about as thick as a matchbook cover that will not collapse no matter hard it's whacked. Personally, it doesn't seem to me to be unreasonable to expect a "hard use" $100+ linerlock to lock as well as an $8 cheapie.
 
All the controversy and opinions aside, you got to admit that in the video, needs work closes VERY easily. I would not like that.
 
The spine whack test is important. If you feel a need for a locking blade in the first place then you want to be sure that it locks. The downward pressure of the whack test simulates the downward pressure on the knife blade as you may encounter through improper rotation of the blade, one of the reasons for a locking blade in the first place. Realistically you should never have a need to test a lock in proper use. However, since its there and there is no back spring keeping the blade in place I would want mine working. I had a CRKT Zytel M16 fail after a lot of use in the same manor. I gave it away as a result. Now I am looking at slipjoints though :)
 
That lock failed under just hand pressure, too. That's not right.

Thanks for the video. That's a fair test. You certainly were not whacking it too hard. I tried my ZT 0560. I had to do it a little harder, and it failed, but only once in a while. Then I could not repeat it. Really surprised me.
 
I would also say that liner locks are going to fail by design. If its just spring tension pinning the lock over then it's really just a matter of greater pressure to force it back out. Nothing actually locks with them. Some are better than others but overtime I wouldn't trust them.
 
I have to admit that this was a bit disconcerting to watch so I just did a quick impromptu test with a control on several of my knives. First I spine whacked them with the common grip of holding the knife by the end of the handle with my fingers out of harm's way. Second, I gripped the same knives very firmly but with my hand right in the way of the blade but close enough to it so that if it did fail, the ricasso would hit the meat of my hand sparing me severe damage. I found a very significant difference in the rate of failure with zero knives failing with the same amount of force while I was "gorilla gripping" the knife, as I would be in a life or death situation. Of course I didn't hit the knives as hard as I possibly could, but I did whack them with the same amount of force and even a bit more that caused them to fail using the end-of-the handle grip.

First, the knives that did not fail with the end-of-the handle grip:
Spyderco Delica 4
Spyderco Military (liner lock)
Spyderco Military (frame lock)
Spyderco Tenacious
Spyderco Gayle Bradley
Emerson CQC-15
Emerson CQC-8
Emerson CQC-7
Kershaw Speedform II
ZT 0700
ZT 0550
Boker Wharcom

Here's the list of knives that did fail with end-of-handle grip, but again, not one failed with an upside down, "gorilla grip":
ZT 0301 (!!!)
Kershaw Piston
Kershaw Blur, de-assisted (this one failed ridiculously easy too, but would not fail with the upside down gorilla grip - I could feel the liner moving, but it did not fail)
Spyderco PPT (this one just has way too early of a lockup and also failed easily with end-of-handle grip, but again, did not fail with the upside down gorilla grip)

Anyway, I've never held much stock in the spine whack test and usually test lock strength with simple hand pressure. To be honest, I still do not hold much stock in the spine whack test, especially when it's being done the way most people do it. I don't recommend doing it the way I did, but at least it proved to me that if you have a good, solid grip on the knife, even under fairly severe force, most modern liner and frame locks should hold up.

I also learned that my Emersons and Spyderco Militaries (my most carried and used knives) have some of the most solid locks around and I have the utmost faith in those knives. :thumbup:
 
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