umnum test from poland

I think it would be hard for CRK to offer an explanation based on a hand full of pictures and vids.






I disagree with the first part of your statement. While some form of conclusive analysis will not identify every possible usage scenario, it has the ability to do what you think should be done - find out the strength of the lock - as well as saving time and money.

Knee jerking based on a lone, poorly documented "test" performed by an amateur can be a rather expensive proposition. I'm sure CRK tracks reported issues with their knives and reacts accordingly.

You're a knifemaker. How concerned would you be if I took one of your knives and induced a failure? For example, by pounding the blade spine with a 10 lb sledge hammer, in an attempt to see if the blade edge would slice through a 2" piece of heat treated stainless steel? :p :D

I got a framelock thats nearly finished so I will do some tests on the lock.

I could stab a fridge if I can find an old one or clamp the folder blade in a vice and hang weights on the handle until the lock fails. For dynamic loads, I could clamp the folder to a swing arm with different weights and let it swing from the same height and hit a stop.

These aren't scientific but they are reproducible and allow people to carry out the same standard tests on other folders and compare the findings.
 
I got a framelock thats nearly finished so I will do some tests on the lock.

I could stab a fridge if I can find an old one or clamp the folder blade in a vice and hang weights on the handle until the lock fails. For dynamic loads, I could clamp the folder to a swing arm with different weights and let it swing from the same height and hit a stop.

These aren't scientific but they are reproducible and allow people to carry out the same standard tests on other folders and compare the findings.

I personally have any desire to see your knife tested...are you saying that you make a stronger knife than CRK ?

Do you have as many knives in peoples hands as CRK ?

Is the frame lock your design ?

Send one of your knives to me and let me beat it up. :)
 
You have a sample size of exactly one knife
and also
These aren't scientific but they are reproducible
I know relatively little about knives, but I do know some mechanics and statistics. Let's keep it way simple.

The sample size is way too low to make any conclusions other than with this specific user, in this one instance, with a lot of unknown parameters (forces, torque etc) which are not reproducable, with things the knife isn't supposed to do the lock actually failed.

Now, compare that with loads of users who did not report this failure. We know they are there, otherwise we probably would have heard of them. Some of them probably abused the knife too (both previous statements are assumptions, but a good working theory). Let's just say, for arguments sake, that CR sold about 5000 umnums (any one know the number?)

Now, let's continue with our amateur statistical analysis. 1 failed lock under heavy abuse with mechanical stresses that might be orders of magnitude higher on different axes than we think they are because we do not know about the angle of insertion when stabbing, the torque that it generates, different forces on different axes etc. versus 4999 non failing locks. This is well within acceptable limits wouldn't you think?

two other well known facts: you can cut down a tree with a kitchen knife, just keep at it long enough and there is the right tool for every job.

In my opinion, this test proves a couple of things:
- the umnumzaan is a very impressive knife.
- things break


And I just love my umnumzaan :D
 
I got a framelock thats nearly finished so I will do some tests on the lock.

I could stab a fridge if I can find an old one or clamp the folder blade in a vice and hang weights on the handle until the lock fails. For dynamic loads, I could clamp the folder to a swing arm with different weights and let it swing from the same height and hit a stop.

These aren't scientific but they are reproducible and allow people to carry out the same standard tests on other folders and compare the findings.

How about including some relevant testing instead for how most people use a folder and tests that are of a real life concern, the like life expectancy of the knife, need for service in it's useful lifetime, and ease of maintenance.

I'm thinking test your knife for 100,000 opening and closing cycles and documenting how the framelock travels accross the blade spine vs the wear on an Umnumzaan. This is a more relevant test IMO. Also find a way to quantify ease of resharpening, cutting efficiency, and lateral prying strength.

In my 15 years collecting, using, and manufacturing experience with knives these are the characteristics that will make or break a knife. I have never encountered a situation where a spine whack or refridgerator stab would be relevant to how I or anyone I know besides a keyboard commando would use a folding knife. (Keep in mind that when using a knife you grasp the handle and hold the lock tightly closed. The tighter your grip with a frame lock the less likely the lock is to slip, and on a spine whak like is pictured in this test there is no grip around the handle. I would love for someone to explain to me how is that really relevant to a knife being used and when do you whack your folding knife against a hard object with a loose fingertip grip in real life? Again I propose this whole thread is now approaching ridiculous!)
 
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I personally have any desire to see your knife tested...are you saying that you make a stronger knife than CRK ?

Do you have as many knives in peoples hands as CRK ?

Is the frame lock your design ?

Send one of your knives to me and let me beat it up. :)

Making a stronger knife than CRK is not the issue and its not hard to do. Plenty of others have made heavy duty folders like ZT and Strider.

I have no idea how many knives are in people's hands.

I didn't design the framelock, so what.

If you want to buy a knife, I suggest you do so in the usual way.
 
How about including some relevant testing instead for how most people use a folder and tests that are of a real life concern, the like life expectancy of the knife, need for service in it's useful lifetime, and ease of maintenance.

I'm thinking test your knife for 100,000 opening and closing cycles and documenting how the framelock travels accross the blade spine vs the wear on an Umnumzaan. This is a more relevant test IMO. Also find a way to quantify ease of resharpening, cutting efficiency, and lateral prying strength.

In my 15 years collecting, using, and manufacturing experience with knives these are the characteristics that will make or break a knife. I have never encountered a situation where a spine whack or refridgerator stab would be relevant to how I or anyone I know besides a keyboard commando would use a folding knife. (Keep in mind that when using a knife you grasp the handle and hold the lock tightly closed. The tighter your grip with a frame lock the less likely the lock is to slip, and on a spine whak like is pictured in this test there is no grip around the handle. I would love for someone to explain to me how is that really relevant to a knife being used and when do you whack your folding knife against a hard object with a loose fingertip grip in real life? Again I propose this whole thread is now approaching ridiculous!)

Stop! You are making too much sense!

The next thing you'll be trying to tell us is that man-made global warming is a ruse.

Please, let these people live in their fantasyland.

Nobody likes a spoilsport.

BTW, thanks for writing that lucid commentary. You saved me the work.
 
How about including some relevant testing instead for how most people use a folder and tests that are of a real life concern, the like life expectancy of the knife, need for service in it's useful lifetime, and ease of maintenance.

I'm thinking test your knife for 100,000 opening and closing cycles and documenting how the framelock travels accross the blade spine vs the wear on an Umnumzaan. This is a more relevant test IMO. Also find a way to quantify ease of resharpening, cutting efficiency, and lateral prying strength.

In my 15 years collecting, using, and manufacturing experience with knives these are the characteristics that will make or break a knife. I have never encountered a situation where a spine whack or refridgerator stab would be relevant to how I or anyone I know besides a keyboard commando would use a folding knife. (Keep in mind that when using a knife you grasp the handle and hold the lock tightly closed. The tighter your grip with a frame lock the less likely the lock is to slip, and on a spine whak like is pictured in this test there is no grip around the handle. I would love for someone to explain to me how is that really relevant to a knife being used and when do you whack your folding knife against a hard object with a loose fingertip grip in real life? Again I propose this whole thread is now approaching ridiculous!)

The way I think about a folder is this. I can't predict how someone would use one of my knives. They might treat it like a safe queen or like a straight knife and expect it to be able to cut, pry, stab and dig without the risk of unintentional closing.

At the moment, I'm working with the limitations of the framelock and the probablility of unintentional closure is not zero. Regardless who made it, this is a fact. If you put enough stress on the lock in a particular direction, it will unlock because it will cam out due to the geometery of the contact surfaces overcoming the forces that keep it locked, namely friction and the force of the locking bar.

It is irrelevant how much you test the lock, the lock can be forced to fail.
 
Making a stronger knife than CRK is not the issue and its not hard to do. Plenty of others have made heavy duty folders like ZT and Strider.

I have no idea how many knives are in people's hands.

I didn't design the framelock, so what.

If you want to buy a knife, I suggest you do so in the usual way.

I'm just saying CRK has been around for a minute and Chris does not just through a new knife together...I think he knew exactly what he was doing by using a cerbec ball. ;)

Thanks, i just wanted to break yours:) i have plenty of knives ...ZT's and Strider's have proven to be no stronger than my Reeves for my tasks....if i ever get stuck in an elevator and have to cut my way out with my folder , Ill let you guys know how it turned out....until then it's all just apples ond oranges :D

I still think the vids posted here are cool :thumbup: :)
 
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http://www.shingcrafts.com/

Wow. that knife is, uh, really something...

"Dreadnought", wow.

"Godzilla" already taken?

I can't believe I just bought an XM-18 when I could have had one of these beauties.....
 
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Making a stronger knife than CRK is not the issue and its not hard to do. Plenty of others have made heavy duty folders like ZT and Strider.

I have no idea how many knives are in people's hands.

I didn't design the framelock, so what.

If you want to buy a knife, I suggest you do so in the usual way.

How are you so sure these knives are stronger? Stronger how? There are more to CRKs than just strength although they are exceedingly strong. None of those knives can match the Sebenza in terms of engineering,f&f or the CS of CRK. I have never heard of you before today but I looked at your Framelock aka RIL and it looks like a larger less attractive version of the Sebenza. Larger doesn't always mean stronger and it's possible the Unmum in that video was faulty. I didn't get to watch it because I'm using a IPhone so I can't say for sure.
 
I got a framelock thats nearly finished so I will do some tests on the lock.


I foresee biased results. :p I have sledge hammers and stainless steel round stock at the ready. :D



…..if i ever get stuck in an elevator and have to cut my way out with my folder , Ill let you guys know how it turned out....until then it's all just apples ond oranges :D


Elevator? It’s a refrigerator you need to cut your way in to. :D
 
Guys, I am planning to order an Umnumzaan tomorrow, but now I am getting worried after reading this topic and watching the videos. Sigh.

It does make sense that the ceramic ball, once it digs a vertical groove in the tang, this groove could facilitate the closing of the knife with minimal force. It'll be like a roller ball rolling downwards in the groove. Anybody can comment on this? And boost up my confidence in this knife once again...
 
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