I have read with interest, and sometimes with frustration, the comments made about testing and Umnumzaan performance. Whether it was the Polish video thread or any of the others, we have chosen not to lock the threads because free discussion is good, but I can agree with posts #14, 16 and 19!
I am very impressed with the way the Umnumzaan in the Polish test performed. It went through all kinds of tough testing and it performed extremely well. After examining the knife, I have come to the conclusion that because it would not fail, it was modified to reduce lock tension and therefore fail the spine whack test. As I have said before, my knives always tell papa the truth when they come home!
This can be seen clearly in the photograph which shows the back handle slab of the test Umnumzaan (above, with clip attached) alongside the handle slab of the Umnumzaan that I have carried in my pocket every day for two years (below). The locking bar of the test knife does not lie as far over as that of my knife, showing that the tension on the lock bar has been reduced.
There continue to be comments implying mistrust of the Umnumzaan ceramic ball lock up system. The Umnumzaan is tough and any doubters of the strength of the ceramic ball need to do their homework on strength of materials pertaining to ceramic ball bearings. These balls are hard and tough. Example: put a ball on a steel plate and hit it with a 1 lb machinists hammer (pall peen). It indents the hammer and the steel plate and does not shatter. You can hit it hard enough, in fact, where it will drive itself into the plate completely. The small indentation caused by the ceramic ball in the lock ramp has no effect on the lock of the knife as has been speculated by some. That is merely because the steel is softer than the ball; it will only indent a small amount and not go any further. The Umnumzaan is the next step in the progression of the integral lock mechanism that I invented in 1987. It is an improvement over the Sebenza.
While there are many individual posts I could answer, I have chosen just two to comment on:
Quote: Sweet hitch-hiker What?! thread, post #17:
I know that knife was thoroughly abused, but i was fairly surprised about how easily it did fail the spine whack test- even on a finger.
The knife surpassed expectation on the treatment it received it failed because it was modified.
Quote: Goldistheanswer Umnum Test from Poland thread, post #250
Every knife has weaknesses and will fail at some threshold of abuse, and I know the SnG has at least one documented weak spot, but for me the ceramic ball design of the Umnum is too much of a tradeoff in favor of "ease of use" and "mechanical bliss" at the expense of outright robustness. While I do not wrist flick my Umnum, I do thumb flick it all the time. It *is* mechanical nirvana. However, given Mr. Reeve's acknowledgement that an even slightly out of tolerance ball will cause the lock to fail, if my life depended on it, I would not opt to carry the Umnum.
My knives will still be performing reliably in 20 years when others are floppy and sloppy and not much use. I have the knives and the history, to prove it. 2012 will be the 25th Anniversary of the Sebenza Integral Lock Mechanism© we have learned a little in those years! The Umnumzaan ball lock mechanism is as positive and secure as any integral lock on the market, provided it is kept in the specifications with which it left our factory.
Anyone who has toured our factory knows that we are open about how we do things and have no secrets. Anyone can tour our factory any time. If I am there, I will do the tour myself and that is not true for some companies. Besides being open and honest, there is only one secret in knife making where to buy a big enough barrel of elbow grease!
To all my supporters, thank you for the kind words. All of us at CRK consistently try to give all of you the very best products and the best service at the best price.
Chris
