Seller admiting to doing spine whack tests (as a selling point)...

Macchina

Macchina

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I am looking at buying a nice knife for an excellent price, but in the listing the seller says the knife passes the spine whack test :thumbdn:! That is like saying a used car passes a front end highway collision test! He goes on to say the knife has some vertical blade play, well duh, you induced it on purpose! I want the knife, but I don't the leftovers of somebodies stupidity. If the lock bar isn't badly bent or deformed, the knife will be worth it, but I am taking the risk of this thing being worse than I imagine.

If any of you haven't read about spine whacks, please don't do them. It has been proven to be destructive to liner locks and If a "test" has the word "whack" in it, it's probably not too scientific. We don't do concrete cutting tests, nor do we do flame resistance test, why do the spine whack test :confused:...?

I messaged him about whether he actually spine whacked the knife, or if he is presuming it would pass the test bassed solely on how strong the lock "feels".
 
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Spine Whacks like I showed in my Video are fine, but any harder than that and one will likely damage the knife.

The purpose of the Spine Whacks is to make sure the lock is working properly, not as a destructive test.
 
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Spine whacks are a good test of lock strength, the idea being that you subject the knife to worse conditions then it is ever expected to have to handle. I like the spinewhacks Cold Steel subjects their folders to, but I wouldn't want to own the tested knives, I'd rather get a new one... knowing its identical twin survived a rough test.
 
Hmm.. not big on destructive and/or abusive testing myself but a decent lock ought to be able to withstand some stress. Obviously, testing by "spine whacking" should not mean attaching the knife to a 3' steel pipe and striking as hard as possible against an anvil or such.. and then complaining about a weak unreliable lock. :D
 
Frankki said:
Hmm.. not big on destructive and/or abusive testing myself but a decent lock ought to be able to withstand some stress. Obviously, testing by "spine whacking" should not mean attaching the knife to a 3' steel pipe and striking as hard as possible against an anvil or such.. and then complaining about a weak unreliable lock. :D
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I disagree completely (I agree with your point, but I don't think this is what a spine whack test is). If it is done lightly, I agree that it shouldn't hurt the lock, but from what I've seen of people doing it, it's not a tap because the purpose of the test is to see what kind of strike the spine can take. Liner locks are designed to put a little pressure on the tang so that the opposite part of the tang is held flush to the stop pin. It is the stop pin that is designed to take load. The mechanical advantage on the liner lock when a 4" blade is struck on the end is incredible and it doesn't take much to induce blade play by deforming the liner lock bar.
 
If the lock bar isn't badly bent or deformed, the knife will be worth it, but I am taking the risk of this thing being worse than I imagine.
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You aren't really going to buy this are you? :confused:
 
cziv said:
You aren't really going to buy this are you? :confused:
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I'm waiting for more pics and details from the seller. I won't buy if it looks like the vertical play was induced by the spine whacks. I will also only buy if I can return it.
The price is almost too good to pass up ($80 for a lightly used [and spine whacked] SERE 2000 on another website). The seller is claiming the spine whacks are a good thing, but it just worries me that I don't know what (if anything) the spine whacks did to the knife.

I've held knives before that were spine whacked and the liner lock will slip all over the face of the tang because it has been deformed and no long is angled to properly engage the lock face. I've also accidentally spine whacked a few of my knives lightly (drops with the blade open where the spine may have hit the floor, withdrawing a knife from a tight spot, etc.) with no damage done whatsoever.
 
cj65 said:
No, not the spine whack thread! It is like a case of herpes. It keeps coming back, festering shanker that it is! Do not buy a whacked knife!
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I've always wondered about these tests; why on earth would anyone want to do this to a knife? I can see CS doing this to demonstrate lock strength in a video, because . . . well . . . LT & his crew are kinda strange like that (but I do like some of their knives) but the 'spine-whack-test' has no place in the real world of knife usage, IMHO.

cj65 said:
I did a spine whack test on the BF Sebenza pass around.
***
This resulted in a flesh wound to my spine. However the mole did not grow back. ;):D
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But the big ugly one on your shoulders is still there. :D :p

thx - cpr
 
Spine whack or not, why would you consider buying a second hand knife with virtical blade play in the first place?
 
orca8589 said:
I've always wondered about these tests; why on earth would anyone want to do this to a knife? I can see CS doing this to demonstrate lock strength in a video, because . . . well . . . LT & his crew are kinda strange like that (but I do like some of their knives) but the 'spine-whack-test' has no place in the real world of knife usage, IMHO.



But the big ugly one on your shoulders is still there. :D :p

thx - cpr
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It is a valid test for lock strength so show how strong the lock can be, but I wouldn't pound my knives so hard as to do damage to it or try to make the lock fail.

Most knives will fail this test if you pound them hard enough and enough times. That is abusing them. ;)

Lightly hitting them say 5 times hard enough to dent the wood is hard enough, any harder than that is abuse. ;)

I have however pounded one of my current knives to the point that would cause failure in most others. It was the Strider RW-1 and that was after my video I did when I had to get it fixed. Even after I loosened it up in the video I pounded it like 30 times extremely hard and the lock held. I am talking about over head swings here. Don't ever try that with most knives on the market today because they will fail.
 
This can and should be a straight up and straight down buy, seems to me.

The fella is offering to sell you a knife. He says it is in excellent mechanical condition but that it does show some wear mostly a few small marks from honest wear. You buy the knife from him with the right of return. That is if it is not as described, or what you want, you can return it and get your money back. If the fella does not offer right of return don't get it.

In this case a fella says the knife is in X condition and has passed all his stress tests or what ever goofiness. His tests are irrelevant. What is relevant to you is the condition he says the knife is in..."excellent", very good, good or poor and that you have a right to return the knife if it is in less than the condition you both understood it to be in. That is all. Keep it simple and clean.

If he is selling a worn and damaged knife only get it if you want a worn and damaged knife. If he says the knife is in very good shape get it if you want that but with a right of return if it is not. You are buying the knife. You are not buying whatever tests he said he did or that he says his grandpappy did. Keep it simple.

tipoc
 
I admit to spine wacking a few of my linerlocks. I'd never owned one until about 2 years ago - being a lockback guy before I became active here and bought knives like a few Spydercos with LL's.

By comprarison to Jim's tests they were verrrry mild. I'd put my big dictionary on TV tray with a towel on it and lightly pop the spine on my test pile. That's the extent of my spine wacking tests.

I'd never buy a spine wacked knife with vertical blade play - even at a great price, but YMMV. That's probably why it's being offered at a great price! :)
 
I asked him if he did in fact spine whack it or if he was just presuming that it would not fail a spine whack test. He said he spine whacked it, so I passed on it. No matter how good of a deal it is, I decided I wouldn't carry it if I wouldn't trust it.
 
Do not buy that....I don't believe in spine whack tests at all. Makes no sense it's like hitting your new hummer with a bat to show how well it takes a baseball bat to the hood. You shouldn't be doing something so stupid with a knife that it gives out.
 
tipoc said:
This can and should be a straight up and straight down buy, seems to me.

The fella is offering to sell you a knife. He says it is in excellent mechanical condition but that it does show some wear mostly a few small marks from honest wear. You buy the knife from him with the right of return. That is if it is not as described, or what you want, you can return it and get your money back. If the fella does not offer right of return don't get it.

In this case a fella says the knife is in X condition and has passed all his stress tests or what ever goofiness. His tests are irrelevant. What is relevant to you is the condition he says the knife is in..."excellent", very good, good or poor and that you have a right to return the knife if it is in less than the condition you both understood it to be in. That is all. Keep it simple and clean.

If he is selling a worn and damaged knife only get it if you want a worn and damaged knife. If he says the knife is in very good shape get it if you want that but with a right of return if it is not. You are buying the knife. You are not buying whatever tests he said he did or that he says his grandpappy did. Keep it simple.

tipoc
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I strongly disagree with your bolded statement. He can describe the condition of the knife all he wants, but he can't tell me things like the angle of the lockface to lock bar, or if the liner lock is slightly bent, or if forward pressure on the liner lock has been reduced from OEM. Condition descriptions can only go so far, beyond that you have to look at what the knife has been through. If a test is destructive, it matters very much! Every time you spine whack a blade it weakens the liner lock. If a liner lock does not fail the first 5 intentional spine whacks, what's to say it isn't weakened to the point of failing on the sixth spine whack that you do on accident during use?


There is a reason you don't do destructive tests on things you use. You don't see a rockwell test dimple on the edge of your knives. You don't see the results of corrosion testing, or electrical shock resistance, or tensile test, or any other destructive tests because they're destructive. As with any other item, you either trust it's reliable from the manufacturer (or test it in an nondestructive way), or you don't buy it. If the test weakens the knife, then you can never trust it after weakening it because your test results are different after each testing.

You don't buy new crash tested cars, you don't buy SAAMI max pressure barrels, and I don't buy knives that have been spine whacked.

As for the rest of your post, I agree. I inquired if he actually spine whacked it or was presuming it'd pass a spine whack and when I found out it was spine whacked, I passed on the deal. I agree that I'd be buying damaged knife and I cannot accept that at any price.
 
I've never had to cut or chop or pierce anything with the spine of my knife. If you are that afraid of the lock failing then use a fixed blade. Do you stab car tires to see if they can stand up to being punctured. A good test of a knife is carving wood, cardboard, food, etc.
 
michaelmcgo said:
I inquired if he actually spine whacked it or was presuming it'd pass a spine whack and when I found out it was spine whacked, I passed on the deal. I agree that I'd be buying damaged knife and I cannot accept that at any price.
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That's good. :thumbup:
 
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