Spine whack testing: valid or not?

[EngrSorenson]

i have often wondered what do people do when they need a cutting edge for doing knife things after they just got done splitting wood with the knife.

In general, this isn’t a big problem. Clear grain wood supports the edge from both sides evenly. After there’s sufficient penetration (giggity) the wood starts to split and ride high on the knife away from the edge. I’m not a big batonning guy, but I’ve done it and been surprised when the edge isn’t mangled.

It’s been covered in depth loads of places, but generally the concern with batonning folders is whether or not the individual parts can take the abuse. There’s probably 10x the failure modes in a folder compared to a fixed blade.

Now “can” vs “should” is another topic. Battening or spine whacking, my concerns are the same; are we introducing a problem by beating on these things to make sure there’s no problem?

 

[Grizzly3]

Which came first, the spine whack tests or the triad lock? Are these tests designed to highlight the strength of the triad, ignoring the side to side weakness that may still be there? I don't know. I just bought my first CS folder, a Code 4 and at 76 I'm not sure I need that strong of a lock. It is a bit of a pain to close. I much prefer other designs. I went about 18 years with a slip joint before locks became popular. We were careful to keep our fingers out of the way of a potential blade closing suddenly. Now, we put our fingers under the blade and trust the lock. I'd hate to have one of these scary sharp blades close on my fingers today. I may wind up giving this one to a grandson to enjoy. I just wanted to try out a tanto and think I may want a narrower blade, something like a Civivi and maybe a weak button lock . It doesn't make sense to beat the heck out of the back of the blade to ensure it holds up to such treatment. Have we been watching JoeX too long?

 

[Guy McVer]

Now, we put our fingers under the blade and trust the lock.

You shouldn't trust the lock. A lock is a safety feature. It's like a seat belt. Seat belts can fail. Likewise, any lock can fail. Just as you still drive cautiously, obeying the rules and trying to avoid getting into an accident where the seat belt would come into play, so should you follow proper knife usage guidelines and try not to use the knife in a way in which the lock would come into play.

I say it all the time: locking folders can give people a false sense of security and lead them to form bad habits which make accidents more likely to occur.

 

[Delgadonine]

You shouldn't trust the lock. A lock is a safety feature. It's like a seat belt. Seat belts can fail. Likewise, any lock can fail. Just as you still drive cautiously, obeying the rules and trying to avoid getting into an accident where the seat belt would come into play, so should you follow proper knife usage guidelines and try not to use the knife in a way in which the lock would come into play.

I say it all the time: locking folders can give people a false sense of security and lead them to form bad habits which make accidents more likely to occur.

This is a better example of the point I was trying to make using the Fire Arm scenario. 'User Error' leads to more injuries, no doubt. Negligence increases the chances of an error, therefore injury.

'Bad luck' or 'that was weird' circumstance is mutually exclusive of a 'spine whack'.

 

[jux t]

You shouldn't trust the lock. A lock is a safety feature. It's like a seat belt. Seat belts can fail. Likewise, any lock can fail. Just as you still drive cautiously, obeying the rules and trying to avoid getting into an accident where the seat belt would come into play, so should you follow proper knife usage guidelines and try not to use the knife in a way in which the lock would come into play.

Seatbelts go through hard use testing, thank goodness. Yeah you shouldn’t be relying on them, but at least you know the designs had to be tested.

 

[brancron]

A spine “light whack” test (not a smash but a firm knock) is perfectly valid. Any locking knife that fails such a test is defective. It’s hard to believe this is subject to reasonable disagreement.

 

[EngrSorenson]

Seatbelts go through hard use testing, thank goodness. Yeah you shouldn’t be relying on them, but at least you know the designs had to be tested.

Right, and seatbelts are a great example of how regulations, as annoying as they are, build consumer confidence. Most of us aren’t out there testing the seatbelts. (And by the way, how many stories are out there still lingering about how people believe seatbelts kill? More than enough that they had to address that in my driving classes in the early 2000’s)

I think this brings up a good point. Feeling the need to spine whack might be an indicator of confidence in the product, regardless of whether or not the product can handle it.

 

[EngrSorenson]

Reminds me of a story from ~5 years ago. An older Chinese lady was getting on an airplane and tossed a coin into the engine on her way to board for good luck. If you want to ensure you have a bad travel experience, throw some foreign objects in a jet engine.

Similarly, I watched a guy on YouTube (I wish I could find the video again) manhandling an Opinel with the virobloc engaged. He struggled for 5 minutes wiggling it and forcing it shut before he was able to shut it, which of course it did, violently, cutting himself in the process, and the title was the lock on an Opinel sucks.

I think the Opinel lock did great.

 

[navman]

(Holds up trigger finger) "This is my safety, sir."

 

[Delgadonine]

A spine “light whack” test (not a smash but a firm knock) is perfectly valid. Any locking knife that fails such a test is defective. It’s hard to believe this is subject to reasonable disagreement.

I look forward to seeing your data.

Exactly when does proper use of a knife lead to failure? How often? Who repeated the study?

The topic used the word 'valid'. That's not a word one uses casually.

 

[Delgadonine]

(Holds up trigger finger) "This is my safety, sir."

'I don't handle a tool or weapon until I know how to do so!'

 

[SharpBits]

Unless the majority of the industry gets together and decides on a set of formal tests, there will be no valid data. That leaves the individual to decide how valid their test is in relation to their use.

We really do not want any government involved in setting testing standards as they will be just as likely to declare knives inherently unsafe.

 

[EngrSorenson]

We really do not want any government involved in setting testing standards as they will be just as likely to declare knives inherently unsafe.

my comments on seatbelts weren't really directed towards being for or against government involvement with knives, merely that there's a regulation, or standard, that must be met for seat belt safety.
The industry could develop it's own standard and regulate itself accordingly, which is what you described here:

Unless the majority of the industry gets together and decides on a set of formal tests, there will be no valid data

Forget about how robust a lock should be, people can't even agree on what the fundamental design requirement of a lock is.
If it ever became a big enough concern, or profitable for the knife community, they could come up with a tiered knife lock system.

Ex. This is a type 1 knife lock: Designed to prevent accidental closure under light use, such as food preparation and cleaning game.
Ex. This is a type 2 knife lock: Designed to prevent accidental closure under heavy use, such as battoning, chopping and personal defense

Then the industry could decide where to draw that line.

I don't see it happening, but just for the sake of kicking around ideas it's a fun exercise.

 

[SharpBits]

my comments on seatbelts weren't really directed towards being for or against government involvement with knives, merely that there's a regulation, or standard, that must be met for seat belt safety.
The industry could develop it's own standard and regulate itself accordingly, which is what you described here:


Forget about how robust a lock should be, people can't even agree on what the fundamental design requirement of a lock is.
If it ever became a big enough concern, or profitable for the knife community, they could come up with a tiered knife lock system.

Ex. This is a type 1 knife lock: Designed to prevent accidental closure under light use, such as food preparation and cleaning game.
Ex. This is a type 2 knife lock: Designed to prevent accidental closure under heavy use, such as battoning, chopping and personal defense

Then the industry could decide where to draw that line.

I don't see it happening, but just for the sake of kicking around ideas it's a fun exercise.

My government comment was not directed at you, just hopefully heading off any attempt at getting any government involved.

Spyderco has set their own lock standards, but I'm not sure outside of their MBC rated locks how formal it is.

 

[Blues]

If you use your knives with the thought the lock may fail, it's less likely you're going to be injured by some boneheaded maneuver.
(And if you use the knife in the manner it was intended to be employed, even less likely.)

I've had more sutures in both hands than most folks...and none of them came from a folder. Go figure.

 

[EngrSorenson]

just hopefully heading off any attempt at getting any government involved.

*puts down pen before signing letter to representative*

 

[Delgadonine]

If you use your knives with the thought the lock may fail, it's less likely you're going to be injured by some boneheaded maneuver.
(And if you use the knife in the manner it was intended to be employed, even less likely.)

I've had more sutures in both hands than most folks...and none of them came from a folder. Go figure.

Chainsaws?

You've been juggling chainsaws again?

Am I right?

 

[Blues]

Chainsaws?

You've been juggling chainsaws again?

Am I right?

I haven't done any mayhem to myself with one of those.



(Yet.)

 

[J. Doyle]

my comments on seatbelts weren't really directed towards being for or against government involvement with knives, merely that there's a regulation, or standard, that must be met for seat belt safety.
The industry could develop it's own standard and regulate itself accordingly, which is what you described here:


Forget about how robust a lock should be, people can't even agree on what the fundamental design requirement of a lock is.
If it ever became a big enough concern, or profitable for the knife community, they could come up with a tiered knife lock system.

Ex. This is a type 1 knife lock: Designed to prevent accidental closure under light use, such as food preparation and cleaning game.
Ex. This is a type 2 knife lock: Designed to prevent accidental closure under heavy use, such as battoning, chopping and personal defense

Then the industry could decide where to draw that line.

I don't see it happening, but just for the sake of kicking around ideas it's a fun exercise.

You forgot about type 3 locks:

Designed to prevent accidental closure under extreme use such as a headbutt from a rogue flying sheep.

Other than that, it's a decent idea.

 

[SharpBits]

I use a spray for rogue flying sheep. It must work because there have never been any around me. #science