Umnumzaan fails spine whack? (not my vid)

[J_Curd]

Assuming the act of stabbing the fridge was a straight line force along the longitudinal axis of the knife, we should expect that the stop pin, the pivot and the lock bar will equally absorb the impact force. However, if you examine the video, the individual in question prises the blade from the fridge by placing downward force on the handle. Due to the fact that the steel of the fridge has effectively wedged the blade, the pivot now acts to shift the force towards the spine of the blade and directly on the lockbar rather than the stop pin. This extreme pressure on the lock bar was repeated as many times as you see knife punctures. No lock mechanism on a folding knife is designed for that degree of stress. At that point, the damage was done. We have no knowledge as to how the knife performed under a 'spine whack' in that vid as none were performed. For all we know, the lock failed when he pulled the knife out of the fridge while off camera. As well, for all we know, he stabbed the knife into the fridge repeatedly off camera or otherwise abused the knife before the vid of the 'spine whack' failure.

I feel that after such abuse as was illustrated, it would be inappropriate to condemn any folder or lock mechanism. The actions simply exceeded the design criteria.

I owe you for summing that up beautifully. Thank you.

 

[chanwahyaoh]

Soooo, when knife is HYPER overextended? After single extension of 3mm(1/8inch )? What about being 100 times extended of 1/16inch, and what about 1000 times being extended of 1/32 inch? Because Umn has no lockbar stabilizer, so overextension will happen from time to time while closing.
But there is another thing - if overextension is the reason of failure it means that Umn is a knife you damage/destroy its lock with one single, simple move of finger. Just grab then knife, open the blade, extend the lock and tadam - your great new knife is now useless.



http://www.youtube.com/watch?v=6ruVryahT7c
Spyderco tenacious, same tester, same fridge. Not every knife fail those tests.

I have an Umnumzaan and I have to say that if overextension of the lockbar simply "happens" with your copy of the knife, then I'd have to say that it's defective and should be sent back immediately.

I always admired the merits of the Hinderer lock stabilizer...until I handled a sebenza (and later on the Umnumzaan). After using both those knives I learned that the stabilizer is not necessary if the lock is designed properly.

On the Chris Reeve folding knives I've had - It would take a very large degree of force to extend the lockbar well beyond what is considered reasonable. And by "very large", I mean one would need artificial leverage - a pry bar or some mechanical force to get it as far open as the pictures I saw in the original thread in the Reeve Forum.

 

[idaho]

I have an Umnumzaan and I have to say that if overextension of the lockbar simply "happens" with your copy of the knife, then I'd have to say that it's defective and should be sent back immediately.

I always admired the merits of the Hinderer lock stabilizer...until I handled a sebenza (and later on the Umnumzaan). After using both those knives I learned that the stabilizer is not necessary if the lock is designed properly.

On the Chris Reeve folding knives I've had - It would take a very large degree of force to extend the lockbar well beyond what is considered reasonable. And by "very large", I mean one would need artificial leverage - a pry bar or some mechanical force to get it as far open as the pictures I saw in the original thread in the Reeve Forum.

Thanks for that info. I didn't handled either Sebenza or Umn for much time, so I cannot say whether it is realy that hard to overextend the lock - probably you are right. I will just wait till that particular Umn will get to CRK, until that moment we can only speculate.

 

[Twindog]

I can easily extend the lock bar on my Sebenza beyond the handle. I didn't try to move it very far past, maybe 1/16th, if that. It was obvious that I could have taken it much farther. There was plenty of flex and no memory, but it took very little pressure.

When the guy was stabbing the fridge, he may have been squeezing the locking bar in, preventing lock failure. Any RIL knife that fails the spine whack test when slapped against a pinky is a broken knife. I can't imagine that stabbing a fridge would harm my Sebbie in any way, other then screwing up the edge.

 

[Cotherion]

He did not damage the folder I think. If he did not over extend in order to take a picture of the ceramic ball (he/she bent lockbar far out until ball can be seen) then the folder would have been in better shape. Sure as hell it'll take a pinky whack.

Anyone have a custom framelock or quality production framelock? Care to sacrifice (hyper-extend) one of them in the name of science?

 

[Tony8179]

I've been watching these threads since the beginning and I figured I'd finally speak up.

So where does the severe abuse happen?

I agree with Flamtnbkr. Refrigerators aren't all that tough as long as that outer piece of steel isn't Stainless. This one obviously doesn't have a stainless shell. A knife is a tool and in my humble opinion, a knife made by a company with a reputation like CRK should be able to stand up to some thin metal, styrofoam, and plastic. I'm not seeing much lateral force or twisting of the blade during the stabbing or removal of the knife so I can't imagine that's the problem.

The overextension of the lockbar may be where this failure began. This overextension can easily take the spring/memory out of the lockbar to the point where the lockbar wants to slide away from the lockbar interface of the blade instead of into it further.

There seems to be alot of anger about this test. I'm not really understanding why. These guys can test the knife in any way they see fit. If they find failure after these tests then I'm sure CRK is very interested to find out how and why the failure happened. CRK hasn't issued a statement or even seen the knife for that matter. This may have been one that slipped through the cracks and was faulty already. It may be from the overextended lockbar, it may be from the stabbing, it may be that the Ceramic ball framelock isn't all it's cracked up to be.

Like it's been said earlier and even earlier still. Save your judgements until CRK has the knife and can check it out and make a statement. Until then, everything is conjecture and heresay. Definitely don't be so ignorant as to call this guy stupid or slam the entire Polish race because of this test.

 

[nate3993]

I'll just quote what one of our members said (and Esav also):
rustle

If you have a tiny bit of respect both for manufacturer & tester you can follow this advice

One more thing:


Link under owner's avatar is there for some reason
http://www.knives.pl/www/artykuly/testy/crk_umnumzaan_fundusz_testerow.html

you still have to look for it. it's not blatantly obvious what was done previously. im sure quite a few people are going to watch the video and not realize the crap the knife went through before that video

 

[orthogonal1]

Assuming the act of stabbing the fridge was a straight line force along the longitudinal axis of the knife, we should expect that the stop pin, the pivot and the lock bar will equally absorb the impact force. However, if you examine the video, the individual in question prises the blade from the fridge by placing downward force on the handle. Due to the fact that the steel of the fridge has effectively wedged the blade, the pivot now acts to shift the force towards the spine of the blade and directly on the lockbar rather than the stop pin. This extreme pressure on the lock bar was repeated as many times as you see knife punctures. No lock mechanism on a folding knife is designed for that degree of stress. At that point, the damage was done. We have no knowledge as to how the knife performed under a 'spine whack' in that vid as none were performed. For all we know, the lock failed when he pulled the knife out of the fridge while off camera. As well, for all we know, he stabbed the knife into the fridge repeatedly off camera or otherwise abused the knife before the vid of the 'spine whack' failure.

I feel that after such abuse as was illustrated, it would be inappropriate to condemn any folder or lock mechanism. The actions simply exceeded the design criteria.

If the knife had enough force applied in the closing direction that the lock was damaged, the knife would have folded without the rather low level spinewacks shown in that video.

Stabbing through the refrigerator did not appear to be that difficult - which is expected given the poor constuction of refrigerators in the last few years. Further, the prying didn't appear to be as forceful as you allege. I've pryed blades out by kicking the handle and the lock maintained - I guess you could be saying the CRK is just not very robust, though.

And, yes, there are many lock mechanisms that can take that type and level of force.

You weaken your discussion by talking about what coulda, maybe, possibly did happen "off camera". First you propose that the apparent refrigerator stabbing was too much for the CRK lock to withstand and damaged the lock, then you go on that possibly some other incident broke the lock. Which is it?

 

[clockman]

Why I seda why are we hashing and rehashing the same basic issues

that WERE ALREADY DISCUSSED after the umnun polish knife test???????????

There must be other topics about knives that are MORE INTERESTING than

going over the same issues again and again and again and again and over

and over and over and over..........................................

 

[JNewell]

These guys can test the knife in any way they see fit.

This is true, but the other side of that coin is that the results are only relevant to the specific conditions of the test and, possibly, only to the specific knife used in the test.

 

[Esav Benyamin]

There seems to be alot of anger about this test. I'm not really understanding why. These guys can test the knife in any way they see fit. If they find failure after these tests then I'm sure CRK is very interested to find out how and why the failure happened. CRK hasn't issued a statement or even seen the knife for that matter.

Actually Anne Reeve did post in the other thread and said they looked at the video but would have to see the knife itself before they could determine what happened.

Don't over-interpret the anger. This is an internet forum; it attracts a variety of people for different reasons. Some will react more emotionally than others. Carry on conversations with those others.

 

[SteelSnob]

Here's the earlier thread on the Chris Reeve forum: umnum test from poland at http://www.bladeforums.com/forums/showthread.php?t=703535

Please be aware that test was preliminary data. Posters from the Polish website joined in to say it was not supposed to be published until they analyzed the data and contacted the Reeves about it. Anne Reeve joined the discussion to say they studied the video but needed the knife itself to determine what happened.

It's just not worth getting worked up about this until based on insufficient data, as even the testers agree.

I would say there's nothing to argue about. Let's wait to hear what they conclude happened.

 

[Tony8179]

This is true, but the other side of that coin is that the results are only relevant to the specific conditions of the test and, possibly, only to the specific knife used in the test.

I agree 100%. That's why I keep the adamant position that all should wait until Chris Reeve can inspect this knife for himself, which I'm sure he will. I'm also sure that either Chris himself or Anne will update us with their findings.

Actually Anne Reeve did post in the other thread and said they looked at the video but would have to see the knife itself before they could determine what happened.

Don't over-interpret the anger. This is an internet forum; it attracts a variety of people for different reasons. Some will react more emotionally than others. Carry on conversations with those others.

Oh, I'm fully aware of Anne's post on the thread over in the Reeve forum. When I said they haven't seen the knife I just meant they don't have it in hand yet to where they can break it down and examine it.

I agree that some react more emotionally than others, but I just don't want to see people popping blood vessels over something than hasn't been fully examined yet. There's no need for the stress. Simply wait until final word comes from the mouths of the pros.

 

[JNewell]

I agree 100%. That's why I keep the adamant position that all should wait until Chris Reeve can inspect this knife for himself, which I'm sure he will. I'm also sure that either Chris himself or Anne will update us with their findings.



Oh, I'm fully aware of Anne's post on the thread over in the Reeve forum. When I said they haven't seen the knife I just meant they don't have it in hand yet to where they can break it down and examine it.

I agree that some react more emotionally than others, but I just don't want to see people popping blood vessels over something than hasn't been fully examined yet. There's no need for the stress. Simply wait until final word comes from the mouths of the pros.

Amen. :thumbup: Newell out.

 

[KyleyHarris]

But you don't want to get your finger between it if it's faulty, do you?

I dont get these comments? A framelock by design is not a self-sufficient locking system. It is an advanced form of a Friction lock. The intent is that you are holding the knife properly and your hand is holding the frame lock in place. The more force you are applying, the tighter the lock is going to be.

If I do a spine tap on a friction lock blade and it pops closed that doesn't show a lack of safety, it shows a lack of proper use for the tool.

 

[udtjim]

Any thing made by man can and will fail, no matter who builds it. Besides there is more than one of those born every second.

 

[zhangmaster12]

Heres my 2C.
Disclaimer: I dont own an umnum.
I dont mind these test, in fact, I like them, gives me an idea of what knives can handle what.

BUT, there a few things i have on mind:
1st: Spine wack.
I believe that these are a good test of a lock, but only if the hand was holding the whole knife like in reverse grip. I cannot imagine the CRK failing the spine whack with you hand holding the lockbar in.
Look at Andrew Demko's spine whack vids. There a tough freakin lock!

2nd: Stabbing fridge
If im getting a Umnum which is touted for hard use, It better be able to stab a fridge and not break on me.

Oh, and it sure as hell better be able to cut the tire.


Anyway, I dont plan on getting an Umnum. I'm more of a fixed blade guy. (no worries about any of those three points )

 

[J_Curd]

Even if this solitary knife is dysfunctional, it is surely not representative of the model. There are far too many satisfied customers to argue otherwise.

 

[missin_hobo]

Originally bosted by philwar
Not disputing this per se, but what do you base this on exactly?

I base it on their reputation, and on my own satisfaction with their products relative to others. Now that I read it over, it was a bit conjectural of me. Apologies, I probably could have worded that better.

Originally posted by unit
Basically I agree, but this video does demonstrate to me that NO DESIGN is good enough to trust to foolish hands.

Very good point. All the same, knife porn is always so much fun to watch.
I wonder how many bloopers there are to the Cold Steel videos; instances where they were testing a knife and it failed utterly. Probably quite a few.

 

[Bierkameel]

bhahahahaha! What?!?!?!

ANYTHING can be brought to failure with enough abuse...

First off, by your logic, if I spend 1k on a folding knife, let's say...a gentleman's folder, it should withstand this abuse and a whatever I can put it through, despite still being a folding knife?
Cost is irrelevant- It is worth what people are willing to pay for it.
I am amazed that people expect the same level of performance out of a FOLDING knife as they do a fixed blade.

Maybe you should read my post again, i said DRESS KNIFE.
A gentleman's folder is a dress knife and not made for hard use, CRK says that the Umnumzaam is made for hard use so it should survive stabbing a refrigerator.