What is the purpose of a spine whack test?

SpacemanSpiff23

SpacemanSpiff23

Joined
Feb 22, 2009
Messages
160
Isn't it about as useful a test as plunging the blade between 2 rocks and then yanking it to one side?

When would a situation ever come up where that much force is applied to the back of the blade in one violent strike like that? It is a completely unreasonable test to perform.
 
Testing the lock's strength.

If you had to stab something or someone:rolleyes:, you may want to have the confidence that your knife isn't going to close on your fingers causing serious injury.

That being said, I have never in my 20+ years as a knife owner, ever needed to stab anything.
 
It is defined as abuse sure, but in the end 5.56 is right. It tests the locks strength so you know when or IF it will close on your fingers. Better to test it wearing gloves then to actually one day have it close on your fingers.
 
I feel a decent spine whack is a pretty good test to do and I do realize that the blade wasn't intended to be a hammer.
Nevertheless, when I'm checking out a potential repair job on a boat my knife is poking, prying and tapping (light spine whacks) away in the area of interest. Lightly spine whacking in areas of dry rot will sing you a song about its condition.
The reviews that Ankerson has done most closely simulate what I do with my knives, though I'm a bit nicer to my blades. I'm more interested in the multi-year/decades long tests.
As much of a no-no as it is, my knives will occasionally be spine whacked. Maybe the baby hammer is on the other side of the shop and I just need to set a few finish nails for reference... whatever.
The only blades that I can recall breaking where on multi-tools, don't think I ever broke one on a basic folder.
Myself, well I don't understand why so many people are stabbing cars and fridges and smashing folders with a sledge in their reviews.
 
5.56 said:
Testing the lock's strength.

If you had to stab something or someone:rolleyes:, you may want to have the confidence that your knife isn't going to close on your fingers causing serious injury.

That being said, I have never in my 20+ years as a knife owner, ever needed to stab anything.
Click to expand...

I like stabbing things like trees and other things you shouldn't with a folder.
Stabbing is a better test of stabbing than spine bashing. I DO test lock integrity first, with progressively applied pressure to the spine or tapping the spine with the second knuckle of the middle finger to get the "feel" of the lock. If you've tested enough locks, this will tell you what you need to know.
I'm a stabbaholic and I still have all my fingers!:D
 
To show my pee pee is bigger than yours. Metaphorically speaking...in the marketing scheme of things, of course...
 
On another forum, there was a question about the strength of various locks, one of them being the liner lock, versus other versions.

Someone asked if the Buck Striders were as strong as the Strider SNGs and so on. And one of the respondants said that some of the Buck Striders had very thin liner locks, and that a simple tap on the back of the spine would be enough for the blade to close. As a consequence, he suggested that before buying one of those knives that a stipulation be made that if the liner lock was insufficient that returning the knife would be alright.

Ahaaaa....

Someone then said that this problem basically didn't occur with actual Striders, just with some of the Buck Striders.

So there you have it....

Testing with a spine whack is not a bad idea after all, is it?

How could it happen in a real life situation? Well, imagine a self defense situation and the knife is swung and the spine hits something like a pipe... you certainly wouldn't want it folding down on your fingers, right?

Folderguy
 
stabman said:
I like stabbing things like trees and other things you shouldn't with a folder.
Stabbing is a better test of stabbing than spine bashing. I DO test lock integrity first, with progressively applied pressure to the spine or tapping the spine with the second knuckle of the middle finger to get the "feel" of the lock. If you've tested enough locks, this will tell you what you need to know.
I'm a stabbaholic and I still have all my fingers!:D
Click to expand...

HAHAHA Stabman, I lol'd:thumbup:

So what's your preferred lock to go around stabbing trees? Don't say fixed blade. :p
 
Folderguy said:
Someone then said that this problem basically didn't occur with actual Striders, just with some of the Buck Striders.

So there you have it....

Testing with a spine whack is not a bad idea after all, is it?

Folderguy
Click to expand...

I had one of the Buck/Striders in question which had the flimsy liner lock (I also had the one with the thicker liner lock).
1) Visually: you could SEE that the liner was too thin.
2) Manual Pressure: gradually increased hand pressure on the spine of the blade caused the lock to slip off, thus failing.

Hence spine whacks still unnecessary.:)
 
5.56 said:
HAHAHA Stabman, I lol'd:thumbup:

So what's your preferred lock to go around stabbing trees? Don't say fixed blade. :p
Click to expand...

I like frame-locks the best, as long as the knife is held in a blade forward grip. The hand holding the lock in place doesn't add to structural strength of the lock, but it DOES prevent the most common cause of liner and frame-lock failures; the lock-bar sliding off the tang.
I also trust AXIS locks, as they have held up well.:thumbup:
A solid lock-back like the Manix can be trusted as well, as long as pocket lint is not in the lock-well.
Compression lock has the advantages of AXIS, and may be better in some ways (I think), so it gets the nod as well.:)
A good liner lock can certainly do the trick, and I still have all my fingers (Wheew!), but I no longer like doing it with them. I can say the Spyderco Military did fine.

Right now the Umnumzaan is about my favourite for it. It is good and tough while still having that, well, pocket knife feel to it. It doesn't seem to freak people out, and it opens quietly. Usually impresses rather than freaks out.:thumbup:
 
stabman said:
I had one of the Buck/Striders in question which had the flimsy liner lock (I also had the one with the thicker liner lock).
1) Visually: you could SEE that the liner was too thin.
2) Manual Pressure: gradually increased hand pressure on the spine of the blade caused the lock to slip off, thus failing.

Hence spine whacks still unnecessary.:)
Click to expand...

In that case, no spine whacks were necessary. And just your story should be enough for people to carefully check out the engagement of the lock. In any case, I confess that I do like to watch those tests that Cold Steel does on at least some of their folders, the spine whack tests, in particular. From what I gathered when watching one of their videos, they test each knife with 5 spine whacks or they won't let it out. If that's true, gotta say I like that...

I wonder how many of their knives don't make it out?

Folderguy

P.S. If memory serves, that test is shown on knives with their Ultra Lock and the Tri-Ad lock.
 
Sometimes, someday someone will make spine whack test on slipjoint... And that will most likely result a lawsuit... :D

I personally do not understand spine whacking but I am sure it serves some purpose to test knife in situation 99,998% of knife user's never will encounter and when someine actually encounter's it no spinewhack test is truthful for the end results ;)

But some overclock computer's and abuse components that way, other people abuse knives.
 
SpacemanSpiff23 said:
Isn't it about as useful a test as plunging the blade between 2 rocks and then yanking it to one side?

When would a situation ever come up where that much force is applied to the back of the blade in one violent strike like that? It is a completely unreasonable test to perform.
Click to expand...

All jest aside , I always spine whack test my locking folders because it increases my condifence in the lock. It is not in the least unreasonable.

It does not void a warranty unless you are beating the snot out of it and somehow cause some part to fail.

It does prove to me that the locking bar, whether liner or frame, on my folder will most likely not close unless I intend it to.

It is not meant/construed to be a laboratory physics test with magnitudes and platitudes and gratitudes and other things that are beyond my ape-like capacity to grasp.

:)

Tostig
 
I just grab the blade and give it a wiggle to test my lock. the spine whack has always seemed like abuse to me. By performing a spine whack you aren't testing anything that the knife would normally do so it's not an accurate test of anything.
 
To quote Ankerson.

"A Hard Use Knife should be able to do some light prying, and a small amount of heavier prying, the pivot should be able to take some force without loosening up too much and the lock shouldn't fail the Over Strike and Spine Whacks. This should be able to be done with the same knife with no adjustments during the test."
 
freedoom said:
I just grab the blade and give it a wiggle to test my lock. the spine whack has always seemed like abuse to me. By performing a spine whack you aren't testing anything that the knife would normally do so it's not an accurate test of anything.
Click to expand...

This is true, however it is nice to see how much a knife can withstand before it explodes in your hand. 99% of us know that a knife is to cut and a prybar is to pry, a hammer is to hammer; however, this is still something that is interesting.
I tend to think of of all this as ELU R&D, it can only help to build a better product later on down the line. Just a thought.
 
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