Just finished a spine whack test on my Buck Select.

[marcinek]

Well... You don't have to be a tactical guy to do the test...

... but it helps. I continue to have a hard time understanding what this test is supposed to demonstrate.

 

[BladeScout]

You left out the part where you flicked the knife open and closed all day checking the locking mechanism :thumbup:

I'll admit to fingering a knife or a flashlight when sitting around.
Drives some people nuts.
My name is BladeScout and Im a knifeaholic and a flashaholic.

 

[jjoanty01]

It demonstrates that during a zombie apocalypse, you cannot trust this knife to bean the zombie hoard over the head with the back of the blade. Gotta make sure you have one of those skull crusher type window breaking pommels on the knife.

 

[jjoanty01]

I'll admit to fingering a knife or a flashlight when sitting around.
Drives some people nuts.
My name is BladeScout and Im a knifeaholic and a flashaholic.

Heheh... my name is jjoanty01 and I have a knife problem. My problem is I don't have enough knives :thumbup:

 

[Sonnydaze]

For a while, I was able to follow this thread....

 

[chiral.grolim]

I will quote user me2 from a previous thread http://www.bladeforums.com/forums/s...k-tests-not-indicitive-of-lock-strength/page2

The spine whack test is perfectly valid if you expect that your folder might get whacked on the spine. Several users have given examples of that happening during using their knives in tight quarters. Spyderco had a line of knives designed and marketed for Martial Blade Craft, with appropriately stout locks. These should be able to pass a spine whack, since pretty much anything can happen if you're having to use a knife for that purpose. One handed modern folders do not work like slip joints or lock backs with half stops. If the lock lets go, the blade is free to swing. A few taps on the spine will tell the tale. Perhaps standing in a door, and turning around would be a good way to simulate the working scenario where a spine can get some impact. Lock strength (slow load against the spine), reliability (does it fully lock every time), and impact resistance (spine whack) can all be considered and tested by knife owners. None have to be to failure

.

Some claim that applying any sort of pressure to the spine of a knife is already incorrect use and any failure is on the part of a user. Similarly, slamming on the brakes of an automobile must be incorrect use and break-failure is the fault of the driver
Even slip-joints incorporate a spring to provide back-pressure against force exerted on the spine of a knife to keep the blade open, but slip-joints are not designed to withstand much force and so can close on the users fingers inadvertently. The entire purpose of a lock-mechanism is to prevent such accidents. Different locks are designed to withstand different levels of force against the blade spine - again note, the locks are designed to resist force against the spine, not force against the blade edge. Shock-force does occur in "nature" - e.g. hard stabs, accidental contact with another object, even in carving - and folks have been injured due to accidental knife closure from such events. Some locks are designed to withstand this, others are not. The "spine-whack test" demonstrates the strength, or rather the shock-resistance of the lock. Many if not most liner/frame-locks are NOT designed to endure such shock and may disengage readily with light impacts, the type of force as might be experienced if 'yanking' a stuck blade free from a box or piece of wood. It is clear form the design why this is so. Others, like the axis and triad, should withstand this as is once again clear from the design.

I do not understand why the concept of such forces occurring and being the reason behind the invention of these designs is so difficult for some to grasp. If you've never encountered such forces, why bother with a lock mechanism, even something as weak as a slip-joint spring, at all? And why criticize those who prefer a more durable locking mechanism? Why is this controversial? The locks exist for a reason, and it is not to simply add a step to closing the knife. They are intended as safety mechanisms. Do those who criticize these tests also criticize the implementation of safety switches on firearms? What about seat-belts in cars? Afterall, when using the seat correctly, the seat-belt is superfluous as all pressure is exerted against the seat, and shock-force is never exerted outward! ... except, of course, when it IS and then lack or failure of the safety mechanism can result in serious injury...

I own a couple of liner-lock knives, but I am much more careful with them than my "hard use" folders because i understand their limitations, and I understand those limitations because I have tested or experienced them. Without the test/experience, one cannot know what to expect, and that ignorance can be harmful.

 

[Bugout Bill]

Well you know, if you happen to be on a backpacking or camping trip and it's just you and the folder because your fixed blade got lost. The folder must be able to provide firewood for you to survive and live off the land until help arrives.

I don't really see how that is a plausible situation. If I am every going anywhere were I see the possibility that I would need to live off the land (which I would fail quickly at), I carry a fixed blade or have one in reach. If I am ever outdoors and I loose my fixed blade, I will have lost my pants and with it any folders I was carrying (Belt and leg tie down on my big knives). In that case, I am probably going to die. There is a reason why a lot of people carry dedicated neck knives or carry a conventional knife around their neck.

If you lose a large (5-8 inch) fixed blade, you have done something seriously wrong.

Also, why baton with the knife in the locked position?

 

[DarkPatriot]

Well the spine whack test is completely valid for testing whether you're folder can handle being stabbed into a tree to be used as a step to reach the next branch when being chased by a grizzly bear. Think about it, that grizzly is coming after you, you may misjudge the distance to the closest branch and need to jump up and down on the spine of the knife to reach that branch and pull yourself to safety . I agree with Bill, I've been out in the woods for a month at a time before and never lost my fixed blade, maybe you need a more expensive one. I know the more I paid for something, the more closely I pay attention to its whereabouts.

 

[sunandsteel]

I don't really see how that is a plausible situation. If I am every going anywhere were I see the possibility that I would need to live off the land (which I would fail quickly at), I carry a fixed blade or have one in reach. If I am ever outdoors and I loose my fixed blade, I will have lost my pants and with it any folders I was carrying (Belt and leg tie down on my big knives). In that case, I am probably going to die. There is a reason why a lot of people carry dedicated neck knives or carry a conventional knife around their neck.

If you lose a large (5-8 inch) fixed blade, you have done something seriously wrong.

Also, why baton with the knife in the locked position?

I was being sarcastic.

 

[o4tg]

People like the spine whack test, simply because it tells them how tough their liner is. No matter how invalid it is or not, does anyone really not like the peace of mind knowing their knife has a strong locking mechanism? The problem is repeated testing of it will cause undue stress to the liner, prematurely compromising lockup.

In reality though, a hacking test which stresses the stop pin is much more valid at showing the brute strength of a folding knife. I get rocks thrown at me for saying this, but the Buck Vantage line has one of the lamest and weakest stop pin assemblies I've ever seen.

 

[sunandsteel]

People like the spine whack test, simply because it tells them how tough their liner is. No matter how invalid it is or not, does anyone really not like the peace of mind knowing their knife has a strong locking mechanism? The problem is repeated testing of it will cause undue stress to the liner, prematurely compromising lockup.

In reality though, a hacking test which stresses the stop pin is much more valid at showing the brute strength of a folding knife. I get rocks thrown at me for saying this, but the Buck Vantage line has one of the lamest and weakest stop pin assemblies I've ever seen.

Never encountered a problem with my Vantage Select. Which of the Vantage line did you own, and if wasn't for you, there's plenty of knives out there.

 

[BladeScout]

Some claim that applying any sort of pressure to the spine of a knife is already incorrect use and any failure is on the part of a user. Similarly, slamming on the brakes of an automobile must be incorrect use and break-failure is the fault of the driver

In light of the subject that is one of the more spectacular spelling fails No offence.

Further more, I havent seen anybody saying that pressure of 'any sort' on the spine of a knife is 'incorrect use.'
One person would like to see the edge against something prior to putting pressure on the spine.

Even slip-joints incorporate a spring to provide back-pressure against force exerted on the spine of a knife to keep the blade open, but slip-joints are not designed to withstand much force and so can close on the users fingers inadvertently. The entire purpose of a lock-mechanism is to prevent such accidents. Different locks are designed to withstand different levels of force against the blade spine - again note, the locks are designed to resist force against the spine, not force against the blade edge. Shock-force does occur in "nature"- e.g. hard stabs, accidental contact with another object, even in carving - and folks have been injured due to accidental knife closure from such events. Some locks are designed to withstand this, others are not. The "spine-whack test" demonstrates the strength, or rather the shock-resistance of the lock. Many if not most liner/frame-locks are NOT designed to endure such shock and may disengage readily with light impacts, the type of force as might be experienced if 'yanking' a stuck blade free from a box or piece of wood. It is clear form the design why this is so. Others, like the axis and triad, should withstand this as is once again clear from the design.

I do not understand why the concept of such forces occurring and being the reason behind the invention of these designs is so difficult for some to grasp. If you've never encountered such forces, why bother with a lock mechanism, even something as weak as a slip-joint spring, at all? And why criticize those who prefer a more durable locking mechanism? Why is this controversial? The locks exist for a reason, and it is not to simply add a step to closing the knife. They are intended as safety mechanisms. Do those who criticize these tests also criticize the implementation of safety switches on firearms? What about seat-belts in cars? Afterall, when using the seat correctly, the seat-belt is superfluous as all pressure is exerted against the seat, and shock-force is never exerted outward! ... except, of course, when it IS and then lack or failure of the safety mechanism can result in serious injury...

I own a couple of liner-lock knives, but I am much more careful with them than my "hard use" folders because i understand their limitations, and I understand those limitations because I have tested or experienced them. Without the test/experience, one cannot know what to expect, and that ignorance can be harmful.

Obviously something you feel strongly about. Ill tread lightly.

Its not 'difficult for some' of us to 'grasp' (thank you) - its just that it seems kind of silly for 'some,' if you'll permit me saying so.
I dont know what kind of action packed world you live in and it is not like I live especially pampered and protected. I have been to Iraq and to Afghanistan several times and when home I go hunting (hog hunting with knife only - no guns), kayaking, camping and hiking all year round. I use knives quite a bit. Some of them see quite heavy use. But as most of our daily life is planned, I bring a fixed blade knife for the above outdoor activities, which calls for a fixed blade knife.

99,999%* of us dont get into a situation, where the scenario you describe plays out - let alone involving a folder. In short I am fine with letting the remainder of those concerned about such things dwelve into spine whacking and such.

Truth be told, if you worry that must about the strength of folders, there is an easy remedy; get a Spyderco-Perrin Street Beat (or similar).
In the scenarios you envision, it'll be way stronger in any way/situation/scenario, that you can imagine.

Now, I didnt bring a folder when I went to Astan. But if I did, I wouldnt feel 'undergunned' (underknifed?...nah) with a good quality folder from a mid range manufacturer of my choice. In a situation, where I would have to resort to a knife, I would have done a bad job anyways and would be in a world of hurt. Besides one would use any means possible to survive, but thats neither here nor there - the bottom line is, that most of us in our daily routine (be it work or play) dont have to worry about putting vast amounts of stress on our folder. We use them for ordinary purpose 99.9 % of the time. Here at last we can finally reveal what most of our knives are used for (in fact most of them may be 'slightly' overengineered) - see below:

I did some critical thinking and figured out why people do all these crazy tests. I think it's because no one wants to talk about or watch videos of folding knives doing what it is they're designed to do. You know, cut stuff. Listen to this exciting story...

Early this morning there was a stray piece of fabric dangling from my pants so I opened my knife and cut it off. A little later I needed to open a box of diapers for my 2yo daughter and used my knife to cut through the tape on the box. When my wife got home she had a plastic package she couldn't open so I got my knife out and carefully cut the top off. I also sliced an orange into 4 pieces. After that hard day of work my knife slept in the drawer. The end.

In that story I don't abuse my knife. No whacking in any direction, no cutting wood, never paired it up with a hammer...kinda boring. Thanks for reading though!

*Number grasped out of thin air.

 

[BladeScout]

Heheh... my name is jjoanty01 and I have a knife problem. My problem is I don't have enough knives :thumbup:

Sounds like the opposite of a drinking problem (no problem at all; I drink, I fall down, no problem).
I suspect, that your knife problem is widespread here. There is no cure Resistance is futile and all that....

 

[Insipid Moniker]

You learned some of the parameters under which that particular lock will fail. I'm always a bit confused about people challenging the validity of a spine-whack test. It certainly isn't the end-all-be-all of testing, and I don't value it particularly highly, but what is a lock supposed to do, other than protect you fingers against similar forces?

 

[Bugout Bill]

You learned some of the parameters under which that particular lock will fail. I'm always a bit confused about people challenging the validity of a spine-whack test. It certainly isn't the end-all-be-all of testing, and I don't value it particularly highly, but what is a lock supposed to do, other than protect you fingers against similar forces?

Knowing whether or not the lock is going to fail under white knuckling or lateral loads is a lot more valuable that spine whacking.

 

[Orv]

This is the first thread I've read on this forum that had me rolling out of my chair

 

[Bugout Bill]

I was being sarcastic.

My apologies, I manage to fail at emoticons.

 

[Sonnydaze]

I have watched test cars being crashed on purpose on tv...in order to check their safety features, but I'm not inclined to do that myself.

 

[sunandsteel]

My apologies, I manage to fail at emoticons.

No problem.

 

[Insipid Moniker]

Knowing whether or not the lock is going to fail under white knuckling or lateral loads is a lot more valuable that spine whacking.

Agreed, but neither of those is really testing the purpose of the lock, which is to hold the knife open against force applied to the spine of the blade. My slip joints handle white knuckling just fine. They can handle lateral loads as well, though you get into dangerous territory with that.