Spine whacking? WHY????

[ourgon]

It failed because its only ti lock against 60 hrc S35VN. Titanium is strong considering it's weight but isn't that good at shock resist.

 

[Gaston444]

Sal's take is basically what I'm saying. But it's a hell of a lot harder arguing with an innovator and inventor like Sal so I'll let his words and thoughts and practices do the talking from here.

That is worth quoting in full:



Tang - Accidentally hitting the tip of a 4" knife while lifting your arm...Arm weight (say 25 lbs) + force to lift (maybe 10 lbs) = 35 lbs times 4" leverage arm = 140 inch/lbs of force. It doesn't take as much as you'd think to develop some force.

Two opposing, conflicting male arms could easily generate 100 lbs of force times 4" of blade (leverage arm) = 400 Inch/lbs. Could you imagine a serrated Spyderco closing up on your hand? even once? How often is not an issue.

Walt, FWIW - Spyderco has been spine wacking all folders since 1981. We've rejected entire runs over lock defeat. We also have minimum lock strength standards that we use for each model.

sal


Says it all really... Long before I ever came here, I found spinewacking a folder (in my case by butt-spinning a plain edge Cold Steel Bowie Pro-lite upside-down) into the narrow space of a derailed and jammed bike chain, said bike chain force-welded in place by abruptly stopped pedaling force(!), was the only reasonable way to "de-weld" the jammed chain without destroying the whole thing link by link... And ignore anyone who thinks they know better in the absence of tools...

Funny thing is, even with my hand nowhere near the lockbar, it never occurred to me the lock could fail (and this being a great folder, it didn't)... I just didn't make sense to me that it would.

Gaston

 

[ourgon]

Indeed

 

[stabman]

Sal says a "light spine whack of maybe 5 pounds of pressure, before purchasing a knife," and "A light tap" at other times before use, even lighter than 5 pounds of pressure.

That is a far cry from what gets talked about by most proponents of spine whacking.

Sal is talking about what should really be called spine taps.

 

[bodog]

Sal says a "light spine whack of maybe 5 pounds of pressure, before purchasing a knife," and "A light tap" at other times before use, even lighter than 5 pounds of pressure.

That is a far cry from what gets talked about by most proponents of spine whacking.

Sal is talking about what should really be called spine taps.

Those Sebenzas failed by just pushing against the spine. Not even a tap. That's the point. And sal said a light whack of 5 lbs before buying the knife. Can you imagine being a store owner and every person coming in started smacking the crap out of every knife they could? Sal was just being smart. Do a light test before you buy it. Like shaving some arm hair to make sure it's sharp. He didn't say bring in 5 miles of rope and start a rope cutting comparison test either, but people kind of want a new knife to be sharp.


Live and let live. Some people want locks that work like they're supposed to. Some people want steel that works like it's supposed to. Others don't care about actual function, they want the prestige of a brand name. It's all good. There's a place for all of us at the knife table. Guys like Chris Reeve offers something. It may not really work that well but for some people it works well enough and gives them what they want. For others it doesn't. Some people just prove that it may not be for everyone and other people get upset about it.

 

[stabman]

Those Sebenzas failed by just pushing against the spine.

Pushing against the spine is a fine way to do things.
I have never encountered a CRK knife that failed from that though.
I have encountered cheap Chinese no-name knives that did; I was testing them prior to giving them away for free (I had been given then for free for a giveaway).

The weirdest one was a cheap Chinese knife that had failed the hand pressure test, which I then gave some spine whacks.
It passed the spine-whack test, even though it had failed under hand pressure right away!
Weird.

 

[bodog]

Pushing against the spine is a fine way to do things.
I have never encountered a CRK knife that failed from that though.
I have encountered cheap Chinese no-name knives that did; I was testing them prior to giving them away for free (I had been given then for free for a giveaway).

The weirdest one was a cheap Chinese knife that had failed the hand pressure test, which I then gave some spine whacks.
It passed the spine-whack test, even though it had failed under hand pressure right away!
Weird.

I don't know many people willing to test $400 knives like that. Demko tested two in a row and both failed easily. One was really bad. I don't think he'd rig the test and it's not a coincidence that two in a row just happened to fail that badly. I don't own a cold steel but I definitely won't own a CRK, either. But yes, my main carry is a Spyderco military with a liner lock. I've spine whacked it some to know where it fails. I've lightly thrown it into wood to see what it would do. I've definitely stabbed and cut all kinds of stuff with it. I know it wouldn't stand up to a triad lock but it works for me and I believe its limits are good for me while being in a knife I really, really like. Some people can say the same thing about other knives. It's cool. But we shouldn't believe that having a non-functional lock is ok. Just don't put a lock on there to begin with if it doesn't work. It's like having a fake suppressor on your rifle or a cowl induction hood and racing fin on your 4 cylinder stock dodge neon.

 

[caseknife64]

Wanna know what i think???? After sebenza fails, metal screw falls to the floor making a metallic noise as it goes. When he puts on the next knife, he gets a new bolt or what have you out of a box, why not use the same one used on CRK? Then you see a quick tighten, no close up of torque wrench setting and tightend really quick. Could he have put a thick rubber washer on it behind bolt??? we dont know, and again why didnt he use the exact bolt as on first knife. It really couldnt have gone too far. The second one could have had a rubber washer on it and torqued less, not at all scientific. Wait a minute, who is performing this? OHHH the less expensive competitor!!!! I dont own any knives from either camp either....

 

[stabman]

I don't know many people willing to test $400 knives like that. Demko tested two in a row and both failed easily. One was really bad. I don't think he'd rig the test and it's not a coincidence that two in a row just happened to fail that badly.

Well, I sure tested my Umnumzaan with hand pressure.
It came sharp; I don't want sharp knife closing on my hand.

My Hinderer and others get that test too.
Sharp knives closing on my hand are a bad idea.

 

[singularity35]

Sal says a "light spine whack of maybe 5 pounds of pressure, before purchasing a knife," and "A light tap" at other times before use, even lighter than 5 pounds of pressure.

That is a far cry from what gets talked about by most proponents of spine whacking.

Sal is talking about what should really be called spine taps.

Thing is, when I say spine whack I'm with Sal. I don't call it a spine tap because Sal doesn't call it a spine tap.

Unfortunately, when the opponents of spine whacking come out swinging, they make it appear that people test by slamming their knives hard enough to break bone.

But then I find that style of argument very common here. Taking a perfectly reasonable action and making it appear ludicrously grotesque to try to prove their point.

 

[stabman]

Thing is, when I say spine whack I'm with Sal. I don't call it a spine tap because Sal doesn't call it a spine tap.

Unfortunately, when the opponents of spine whacking come out swinging, they make it appear that people test by slamming their knives hard enough to break bone.

But then I find that style of argument very common here. Taking a perfectly reasonable action and making it appear ludicrously grotesque to try to prove their point.

Just look at spine whacks on YouTube.
Most of them are in the "hard enough to break bone" category.

That is why people start threads asking why the hell anyone does it, because that is what is put out there most visibly as spine whacking.

 

[singularity35]

Just look at spine whacks on YouTube.
Most of them are in the "hard enough to break bone" category.

That is why people start threads asking why the hell anyone does it, because that is what is put out there most visibly as spine whacking.

Then there really should be a differentiation, not a blanket condemnation.

I would prefer others to crash test the same model car I have, just like I prefer to have others test the limits of folders I buy.

I'm sure that it's the people who carry a knife with SD in mind are mostly the people who care about sharp impacts on the spine of their folders. Now whether they have to defend themselves everyday or whether they ever have to, is another matter entirely. Just like people who carry guns. These probably don't have to use them everyday as well but want their guns to be reliable.

What I don't understand is that why is it held to be ridiculous when people want their folders to be reliable for SD when reliable guns for SD aren't looked at as ridiculous.

 

[JR88FAN]

It's kinda funny that for a long time slipjoints where just fine and did everything we do with knives and nobody lost fingers unless it was user error.

All this about CRK's failing easily, but when I stab my Insingo's into solid wood, guess what? Nothing happens....

That's about as much pressure as the lock will get, stabbing into material. Anything else and you're using the wrong part of the wrong tool.

If you think CRK locks fail by touching the spine, you haven't used a CRK.
Considering how many people do without issue should tell you that the locks are good if you use a knife for it's intended purpose.
How far beyond? I can say from personal experience, far enough.
There comes a point though when the "wrong tool" or "fixed blade" has to enter your mind....

I am not buying a knife based on the fact that the lock won't fail if I hang an elephant off the spine of the blade.

 

[JR88FAN]

Then there really should be a differentiation, not a blanket condemnation.

I would prefer others to crash test the same model car I have, just like I prefer to have others test the limits of folders I buy.

I'm sure that it's the people who carry a knife with SD in mind are mostly the people who care about sharp impacts on the spine of their folders. Now whether they have to defend themselves everyday or whether they ever have to, is another matter entirely. Just like people who carry guns. These probably don't have to use them everyday as well but want their guns to be reliable.

What I don't understand is that why is it held to be ridiculous when people want their folders to be reliable for SD when reliable guns for SD aren't looked at as ridiculous.

Knives for SD is ridiculous in itself.

It's only advantage over running away would be in a sneaky offensive type situation....
Better off with some pepper spray and a good pair of running shoes.

 

[T. Erdelyi]

Thing is, when I say spine whack I'm with Sal. I don't call it a spine tap because Sal doesn't call it a spine tap.

Unfortunately, when the opponents of spine whacking come out swinging, they make it appear that people test by slamming their knives hard enough to break bone.

But then I find that style of argument very common here. Taking a perfectly reasonable action and making it appear ludicrously grotesque to try to prove their point.

Isn't that what he calls it in the closing line?

A "standard" method of "spine-tapping" for lock reliability that anyone can use and understand if needed.

Indeed

bodog, your ridiculous analogy isn't even worth addressing, it's apples and oranges. Wanna design a knife that survives a vigorous "spine whacking" not real hard but if you want a lock that won't fail get a fixed blade. You can make any lock type fail if you understand what compromises it's integrity. When pocket lint can defeat pretty much any lock if there's enough and it's in the right place then there's always a chance for failure and based on that no lock is safe.

Oh and if you're gonna take the time to periodically spine-whack which after the knife comes outta the box and into your pocket the first time you've compromised that lock unless you can definitively prove that it's in the same exact condition as when it came outta the box. If that's the case I'll carry a fixed blade, even a smaller one can't fold on your fingers.

Last point and I know it's been beat to death too, slip joint folders have been around long before locks and people manage to get the job done, even using it to pry with all without a concern over whether it folds, it's called a folder for a reason.

I'll agree with one point that was made, it's your knife do what you want with it but that also means I can do the same with mine and to me a spine-whack proves nothing.

ETA... keep this in mind too, constantly spine-whacking your lock blade will eventually lead to a failure, it may take awhile but it'll happen. Personally I'd rather have a knife last for a hundred years and work nearly as well as new and look better aged.

 

[Goosey]

Knives for SD is ridiculous in itself.

Nope. They have their pros and cons depending on the situation, just like any other item.

 

[bodog]

Isn't that what he calls it in the closing line?




bodog, your ridiculous analogy isn't even worth addressing, it's apples and oranges. Wanna design a knife that survives a vigorous "spine whacking" not real hard but if you want a lock that won't fail get a fixed blade. You can make any lock type fail if you understand what compromises it's integrity. When pocket lint can defeat pretty much any lock if there's enough and it's in the right place then there's always a chance for failure and based on that no lock is safe.

Oh and if you're gonna take the time to periodically spine-whack which after the knife comes outta the box and into your pocket the first time you've compromised that lock unless you can definitively prove that it's in the same exact condition as when it came outta the box. If that's the case I'll carry a fixed blade, even a smaller one can't fold on your fingers.

Last point and I know it's been beat to death too, slip joint folders have been around long before locks and people manage to get the job done, even using it to pry with all without a concern over whether it folds, it's called a folder for a reason.

I'll agree with one point that was made, it's your knife do what you want with it but that also means I can do the same with mine and to me a spine-whack proves nothing.

ETA... keep this in mind too, constantly spine-whacking your lock blade will eventually lead to a failure, it may take awhile but it'll happen. Personally I'd rather have a knife last for a hundred years and work nearly as well as new and look better aged.

Cool. There's nothing wrong with guys showing that a lock works. Some guys just go overboard with acting like they're going into zombie fights all the time. I believe that's where the animosity comes from. It's stupid. On the other hand, guys obviously want knives with working locks or people wouldn't be buying them so the "other side" calls people who take that stand as being just as ridiculous.

There's a middle ground. People want a lock on a knife or they wouldn't buy one. If they buy one, they probably should want it to work right. To know if it works right, it should probably be tested. Instead of ruining your own knife, it's nice that someone else takes it upon themselves to ruin theirs and post the results. Some guys push the knife to failure so we don't have to. It's appreciated. All the other guys NOT testing should probably just accept what works and what doesn't and all the stuff in between and leave other people the hell alone. Do you think I call traditional friction or slip joint knife fans stupid? Nope, they like what they like. They probably want a friction folder to have some friction and they probably want the slip joint to have a good half stop. It's easy to test for that stuff though. People who want locking knives to work and test to see if they work aren't stupid or ridiculous or whatever. It's actually kind of ridiculous to think they are, especially by a bunch of other knife nuts who probably all own knives with some kind of positive locking mechanism. I bet money most of those guys would whine and cry if the grinds were off, or if it was off center, or if the thumb stud was roughly finished. But say their locks don't work right and they don't care, or if they care it's enough to get mad and debate how people don't really need locks at all, but not enough to support those testing certain aspects of a knife that actually serve a function and for safety reasons should work well. That boggles my mind.

The fact that this is so contentious would probably be considered ridiculous by a good many people so maybe we're all off the deep end and accept that other knife nuts are, too, and all just have fun in the pool we're all metaphorically swimming in. Otherwise, what's the point. They're just tools and we like to have fun with them.

 

[Sticky]

Somewhere along the line we convinced ourselves we need locks that will support a Buick in case we ever find ourselves surrounded by ninjas in a jungle.

 

[bodog]

Somewhere along the line we convinced ourselves we need locks that will support a Buick in case we ever find ourselves surrounded by ninjas in a jungle.

Well, most of us knife nuts like at least some locking knives. And if the knife has a lock, it should work. Most reasonable knife nuts don't expect a knife to support a Buick but most think it should be easy to intentionally disengage and hard to unintentionally disengage. Or maybe I'm flying solo with that mentality. Well, me and every company that takes pride on their knives with locks. Someone is buying them so I assume other people think the same way but I guess it's possible that people really only want traditional, non-locking knives but there's a major shortage of them so they're stuck buying knives with unnecessary and unwanted locks. But if people don't really want locks or care of a lock works well in testing and in real life, why do so many care about lockup and steel inserts and longevity of the life of the lock?

 

[T. Erdelyi]

Bodog, it's all about the knives. It's like motorcycles, I'm happy people are ridin' I'm not gonna get hung up on the type or make of bike you ride, hell it gives us somethin' to talk about it's just that you can only talk about which headlight cover is best for off road when the farthest off road most people get is their driveway in the snow. This is one of those subjects that with a quick Google search turns up tons of reading material and in 20 years of talkin' to a lot of the members here about the same topic we've never gotten anywhere with it. Kinda like the old "Is a Sebenza(or insert any midtech knife company here) really worth the money?"