Kershaw Spine Whack Fail

[Jaytaylor]

I decided to test some cars out seeing as the automotive analogy seems so in vogue here.

None of them could cross a 500m lake, all of them failed to fly and all of them were damaged after being run into a wall........therefore I conclude that all cars are a failure and poor design except for Knight Rider...that will likely pass all tests.

 

[TriviaMonster]

I always thought the spine whack was a silly test. It is. It doesn't really simulate anything I would do in the real world. But, I would be lying if I said I never hit the back of my knife on something trying to make a tricky cut, but that's how it goes. My job requires me to work with what I have sometimes and while not ideal, sometimes I will need to rely on the lock. I've even needed to rest the spine on something to get some leverage to cut what needed to be cut. By all means, if you don't need a lock, that is cool with me. I don't wish you to have to do these sort of things, but when you need it to stay open, you need it to stay open. I can't imagine Hinderer being happy about a light tap closing one of his blades, though. Chicks don't dig dudes with missing fingers.

 

[longbow]

The spine whack is a valid test imho. Knives can and do fail that way whether intentional or not. For instance, this past weekend I had one of my favorite high end folders at our camp on Lake Ontario. I used said knife to trim long grass around the front of the trailer, yep trailer, under an over hang where I couldn't get at with the mover. Bumped the back of said knife during a swing to trim the grass that was longest there. AT first I couldn't figure out why my knife didn't cut cause its a friggin razor. Looked down and the knife was half closed. Thumbed it open and finished the little trim job. These weren't wild un-controlled swings either, but rather short sweeping snap cuts.

So go inside to clean off the blade and kind of examine it. It used to pass the spine whack test but no more. Closes easy now with just a slight bump at the tip on the spine. Matter of fact it closes when knocked against a knuckle on the left hand. It is not even that used to tell the truth. It is a high end liner lock with a BG42 blade and just love this thing. Now also at the camp I had a CS Talon in the bedroom. Forgot I had the knife there in another pair of jeans hanging in the closet. My wife had used this a couple of weeks previously in a pinch to cut down some dead ferns in the front facing the lake. Bottom line is I figured what the hell, so went outside to the deck and gave it a couple of hard ass whacks on the deck railing and nothing. NADA. Figured that is about as hard as I'll beat the thing ever so good enough for me. Did the same type of thing to the high end folder and it closed so fast and hard that if I knew it would fail and I had my fingers there it surely would have caused a good deal of injury. When I was trimming the high grass with it to get a bit better snap to the cut I had it gripped down towards the back for a quick snap cut and I had banged the back edge on a little wooden frame that some bricks lie in a the bottom of our deck steps.

Knives I have that don't fail on me: Tabor big ass folder, CS folders, EKI Super Roadhouse and Super 8, Sebenza, Sebenza clone, District 9 frame lock, Pohan Leu BluePhin BM 710, Lum designed Seki Cut, Boker 2000 knife, and a Timberline Wartac and an original issue Paragon folder. None of these fail with a good bounce off some wood near the tip. The other thing folks seem not to grasp here is that a well made liner lock when it fails should fail in towards the opposite side if it is made correctly. I've owned numerous BM CQC knives and when doing that test on most of them you would see the liner go towards the opposite side a tiny bit. So there ya go. It shouldn't release the blade. keepem sharp

 

[Jaytaylor]

The spine whack is a valid test imho. Knives can and do fail that way whether intentional or not. For instance, this past weekend I had one of my favorite high end folders at our camp on Lake Ontario. I used said knife to trim long grass around the front of the trailer, yep trailer, under an over hang where I couldn't get at with the mover. Bumped the back of said knife during a swing to trim the grass that was longest there. AT first I couldn't figure out why my knife didn't cut cause its a friggin razor. Looked down and the knife was half closed. Thumbed it open and finished the little trim job. These weren't wild un-controlled swings either, but rather short sweeping snap cuts.

So go inside to clean off the blade and kind of examine it. It used to pass the spine whack test but no more. Closes easy now with just a slight bump at the tip on the spine. Matter of fact it closes when knocked against a knuckle on the left hand. It is not even that used to tell the truth. It is a high end liner lock with a BG42 blade and just love this thing. Now also at the camp I had a CS Talon in the bedroom. Forgot I had the knife there in another pair of jeans hanging in the closet. My wife had used this a couple of weeks previously in a pinch to cut down some dead ferns in the front facing the lake. Bottom line is I figured what the hell, so went outside to the deck and gave it a couple of hard ass whacks on the deck railing and nothing. NADA. Figured that is about as hard as I'll beat the thing ever so good enough for me. Did the same type of thing to the high end folder and it closed so fast and hard that if I knew it would fail and I had my fingers there it surely would have caused a good deal of injury. When I was trimming the high grass with it to get a bit better snap to the cut I had it gripped down towards the back for a quick snap cut and I had banged the back edge on a little wooden frame that some bricks lie in a the bottom of our deck steps.

Knives I have that don't fail on me: Tabor big ass folder, CS folders, EKI Super Roadhouse and Super 8, Sebenza, Sebenza clone, District 9 frame lock, Pohan Leu BluePhin BM 710, Lum designed Seki Cut, Boker 2000 knife, and a Timberline Wartac and an original issue Paragon folder. None of these fail with a good bounce off some wood near the tip. The other thing folks seem not to grasp here is that a well made liner lock when it fails should fail in towards the opposite side if it is made correctly. I've owned numerous BM CQC knives and when doing that test on most of them you would see the liner go towards the opposite side a tiny bit. So there ya go. It shouldn't release the blade. keepem sharp

Remind me not to buy a used knife from you.

So you frequently whack the back of your folding knives against wood??!?!??! and substitute a lawn mower / weed whacker with a pocket knife. Both are abuse and I'm not surprised you had a folder unlock on you.

The spine whack is not a valid test as it represents NO real world correct use of a folding knife.


I would re-word the "Knives I have that don't fail on me:" to knives I have failed.

 

[Jaytaylor]

Hammer for cutting paper?

Fail......a poorly designed hammer....clearly!

 

[Pete1977]

I had a Kershaw folder fail a spine whack test. It was a blackout, used for general cutting of mostly rope. I tapped it one day on the back of my work boot and it folded on my fingers. The lock face had peened at some point and the tang slipped off of it with any sort of pressure on the spine or point of the knife. I don't know how the lock face was deformed from normal use but it was a manufacturing problem and not operator error. Locks do fail, even from reputable knife companies.

 

[Insipid Moniker]

If knife A consistently fails under circumstance X and knife B does not fail under circumstance X, all other things being equal, I will pick knife B every single time. Spine whacking does not fully demonstrate whether or not knives consistently fail as there are too many variables, but it gives us a piece of the puzzle.

Now all other things are never equal, so there are many factors that inform my purcbasing habits much more, but if someone is performing a test on their knives that shows several clearly failing and one passing, why wouldn't I factor that in? It might not change my final decision, but it adds data I didn't have before.

 

[longbow]

Here is the point to what I wrote. Sometimes in use you accidentally use a folder in such a way as to put stress on the blade and locking system which I did in this instance. The knife is a high end folder used for survival or so the maker claims. It was a bump and not a whack so to speak. Blade released itself and if I wasn't paying attention to what I was doing it could have meant a trip to the hospital for stitches and I kid you not. Did I deliberately hit it like that, nope. Do I perform a spine whack on my folders for liner locks and frame locks, yep. Is that abuse to me, nope, is it to you yep. When I sell a folder is it reliable in both lock up and blade play etc. yep. So no worries about selling you a knife. Read my f.b. numb nuts and you will see complete satisfaction with what I sell. Also the liner lock is made to fail in towards the knife and not release. That is why they are so hard to get right. Oh yea forgot to include my Super Beast folder for not failing at all. keepem sharp and no sale to you EVER!

Here is a quote from a Bernard Levine paper he wrote on the Walker liner lock and test he did with the knife locking system vs. others of the time: "What's more, when Walker's Locker did finally fail, it

failed in the open position. Instead of closing suddenly upon

failure, as all the other knives did, it seized up and became a

"fixed" blade. So I rest my case.

Thanks Mr. Levine.

 

[Jaytaylor]

Read my f.b. numb nuts and you will see complete satisfaction with what I sell.

Thanks for the insult, the intentions of your post were very clear and your follow up confirmed as much.

 

[B.F.U]

Hammer for cutting paper?

Fail......a poorly designed hammer....clearly!

You ever hear the saying "if you don't have anything productive to say don't say anything at all"?

By your logic that xm 18 you want will be a great cheese slicer!

Not everyone is a collector. The fact that these knives failed this test does not apply only to situations where you actually hit the spine on something. I'm confident if I had used a liner/frame lock (even a high end one) to open a packing tube I received recently rather than a ($60 in this case) back lock I would be injured at this very moment. In order to open the tube I had to apply great pressure in a piercing motion. I did not have a better tool for the job, save a hack saw, because I don't have a million fixed blades. I have one, it is extremely cheaply made, and not full tang. But my $60, linerless back lock did just dandy.

 

[B.F.U]

If knife A consistently fails under circumstance X and knife B does not fail under circumstance X, all other things being equal, I will pick knife B every single time. Spine whacking does not fully demonstrate whether or not knives consistently fail as there are too many variables, but it gives us a piece of the puzzle.

Now all other things are never equal, so there are many factors that inform my purcbasing habits much more, but if someone is performing a test on their knives that shows several clearly failing and one passing, why wouldn't I factor that in? It might not change my final decision, but it adds data I didn't have before.

I think you make a valid point which puts forth a similar idea to the one I said, but in a more logical format.

 

[Karda]

For instance, this past weekend I had one of my favorite high end folders at our camp on Lake Ontario. I used said knife to trim long grass around the front of the trailer, yep trailer, under an over hang where I couldn't get at with the mover. Bumped the back of said knife during a swing to trim the grass that was longest there. AT first I couldn't figure out why my knife didn't cut cause its a friggin razor. Looked down and the knife was half closed. Thumbed it open and finished the little trim job. These weren't wild un-controlled swings either, but rather short sweeping snap cuts.

So go inside to clean off the blade and kind of examine it. It used to pass the spine whack test but no more. Closes easy now with just a slight bump at the tip on the spine.

Here is the point to what I wrote. Sometimes in use you accidentally use a folder in such a way as to put stress on the blade and locking system which I did in this instance. The knife is a high end folder used for survival or so the maker claims. It was a bump and not a whack so to speak. Blade released itself and if I wasn't paying attention to what I was doing it could have meant a trip to the hospital for stitches and I kid you not. Did I deliberately hit it like that, nope.

Thank you for supporting my statements below.
I suppose you don't think that your previous "spine whack testing" contributed in any way to the failures of your knives?
If you are going to hold the manufacturer responsible, you cannot absolve yourself of your own responsibility to be aware of what you are doing during usage, to perform proper maintenance and for proper usage.

keepem sharp and no sale to you EVER!

Don't worry, I don't buy from spine whackers. If I accidentally did and found the lockfaces damaged, the seller would be refunding me.

Folding knives by their design have some inherent risk. A risk that is known both by the manufacturer and the end user.
Which means that the user bears some responsibility in proper usage.
Because a knife is used (or tested) improperly and fails, doesn't mean it is automatically faulty and the manufacturer is solely to blame.

Which is why I consider spine whacking invalid and abusive. Who in their right mind is going to spine whack a knife during its intended usage?
As I said before the design has a known inherently liability that the end user is responsible for having enough thought to comprehend and watch for. Therefore that user should use the knife carefully and as intended because they know it can fold as intended by design.

 

[longbow]

You folks aren't seeing the forest for the tree's. Michael Walker re-invented the locking liner on modern folders. It has been around for many many years in different forms and most not being very reliable. If the liner fails and releases the blade it is not made correctly plain and simple. The intent of Mr. Walker's liner lock design was to make the folding knife using the system more like a fixed blade in that if it fails it fails open and doesn't release the liner lock so it doesn't close on ones digits. So my conclusion from Mr. Levine's testing and Mr. Walker's design is that if it fails closed it ain't right no matter what you guys want to say.

Also what you guys think I sit all day hitting the back of my knives? Give me a break and be logical and do a bit of research on the way Mr. Walker designed this lock. Just doesn't make sense if the knife with a liner lock is designed to fail open as he designed it and it doesn't fail open then it is not made correctly and is unsafe.

Another instance of use on an MOD Tempest. The knife was brand spanking new when it was first released. What a well made tool. Impeccably made. So my wife is in the kitchen using said knife to cut a piece of gasket material she was taking off the door of the fridge. Open the knife for her, hand it to her, she cuts the gasket material like butter, raises up to hand me the knife and hits the spine as she is raising up with the knife, on one of the trays along the door. Knife closes on her fingers and cuts them. Minor cuts but cut none the less. She was not to happy with me or the folder. Sent the knife back to MOD and talked with a gentleman there and explained what happened. Sent the knife in, new knife returned to me a week or so later as I remember and as solid a lock up as one could ask for. I hit the knife out towards the tip and it held like gang buster as a matter of fact it traveled very slightly across the lock face. Perfect. Lost that knife in the house somewhere and to this day it is still lost. So there ya go.

PS Don't think I'd sell to you either Karda

 

[Karda]

PS Don't think I'd sell to you either Karda

PS: Don't think i'll ever ask you to!

 

[Luis G.]

All I will say is this: You are more than welcome to buy from me Karda or Longbow.

Providing full disclosure (Longbow) and asking questions (Karda) is the best way to go about it, it's the responsible thing to do.
No need to judge each other by the way we treat our knives.

Longbow you are correct on liner locks. The proper way to make them is so as to cause the liner lock to go into the knife tang not disengage. However achieving a balance, THAT is easier said than done. As I mentioned it does require very tight tolerances in the entire construction of the knife, a simple mil or two can throw off the linerlock/framelock mechanisms.a
The result however is a very strong lock.

What the Tri-Ad lock, axis lock, CBBG have in common and their real success, imho, is the simple robust design yet ingenious mechanisms that do not require insane tolerances to outperform other locking mechanisms.

 

[Dorito Monk]

I decided to test some cars out seeing as the automotive analogy seems so in vogue here.

None of them could cross a 500m lake, all of them failed to fly and all of them were damaged after being run into a wall........therefore I conclude that all cars are a failure and poor design except for Knight Rider...that will likely pass all tests.

That's because you lack discipline.

(skip to 3:00 or 4:50)

[youtube]4oeJjzdlTuI[/youtube]

Cars can even cross the English channel, and it only takes two episodes of Top Gear to figure out how to do it.

[youtube]WTVPPTV-bQM[/youtube]

Now that I've taken this automotive analogy to the stupidest possible place, let's look at our findings: liner locks are like regular cars - you can use them for every single normal task you'd ever need to accomplish, but you can't spine whack them (or drive them across lakes). Overbuilt locks like the Triad are cracked-out Icelandic nitrous-powered dune buggies, and you can spine whack them (even though you don't need to), or race them across lakes. Just because knives exist that can pass a pointless test, it doesn't mean that a knife needs to pass said pointless test to have value.

(In this analogy, a pointless test can refer to either driving a car across a lake or spinewhacking a knife.)

BAM. Money in the bank. Now go hit your folders against bricks or something. It's pointless as hell but entertaining for the rest of us. Just like Top Gear challenges.

 

[longbow]

You can whack the spine, it's simple, hold the knife upside down point forward and hit it out towards the tip on a piece of wood, not rock, steel etc.etc. If the lock releases it is defective, why cause it didn't fail open.(period) As it was designed by Mr. Walker it is designed to fail open and not closed as in the blade closed on fingers or what have you. Cutting grass that is about 6" tall with a sweeping motion is not abuse of a knife. Bumping knife on wood and having knife blade close is failure no matter how you cut it. Cars ain't got nothin to do with it. But kinda of interesting, but not really cause it ain't got nothing to do with knives.

 

[presz]

Send in the 2 that aren't Blems. Problem solved. You may get charge $10 for a new blade for the Needswork, but the Piston will be fixed for free. You are SOL on that Blem though. That's why I don't buy them any more. Not worth the risk to save 20%. The only Kershaw that I have ever had lock problems is a Blem........You think that could be why it was a Blem? Kershaw has the best warranty department that there is, give them chance to make it right. Lock this thread until then.......then make a new video.

I've had several Pistons and 0350s pass through my hands. Did some spine whack tests on one Piston and two 0350s. Never a budge out of any of them.

The OP's knives must be defective, especially that blem 0350.

 

[ursamajor]

I feel like the spine wack test is the knife equivalent of testing the airbags in your car by driving into a brick wall. Both are pointless and cause unnecessary damage.

The strength of a lock to withstand an impact to the spine is far from pointless. What about the guy who works in a warehouse, and is cutting and moving boxes/bands/etc. What if lifting from a cut, the spine of the knife impacts something, causing the blade to fold on his fingers? Is that irrelevant? In normal use of a strong utility folder, there is ample opportunity for a knife to have a moderate impact on the spine.

To say the strength of a lock is irrelevant on a folder is no different than to say the strength of a tang on a fixed blade is irrelevant.

 

[gwebb]

The whole point of the liner lock (or any knife lock for that matter) is to keep the knife edge from coming down on your hand. The only situation that would cause this to happen would be for you to have some kind of pressure on the spine of the blade, which actually CAN happen in real world situations. Much like the situation the previous poster described. It's not like the OP used the knife like a hammer. He was using the weight of his hand. That is pretty ridiculous. The knife in the video is hopefully a lemon and does not reflect the quality of the model as a whole. When i pay the kind of money that we all pay for knives, I expect more. Period. I do not agree with abusing knives but if you think the video shows a knife owner abusing his knife then you probably arent using yours hard enough. That seems to be pretty typical around here though.