New umnumzaan very difficult to open

M

merlinus

Joined
Apr 24, 2011
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My new umnumzaan is very difficult to open, even with two hands. I have about destroyed my thumbs trying to do it one-handed.

Once the opening process is started, the knife does move more easily into the fully open position.

I have watched several youtube videos, and it seems that it should open very smoothly, and can almost be flicked open using the stud. This is definitely not the case with mine.

Can I expect it to break in over time, or is something amiss?
 
The umnumzaan opens different than a sebenza. With a sebenza, you push up ( away ) from the handle and do a ( rainbow ) arch type movement until locked. With the umnumzaan, you push towards the blade and it will pop open very easily. It's definitely different than a sebenza. Try this and post your results.
 
Are you possibly holding the lock bar? That will push on the detent ball making it more difficult.
 
Nyefmaker, I have done exactly what you suggested, with both left and right thumbs, which are now sore beyond belief.

Daniel, I am definitely not placing any pressure on the lock bar.

My small sebenza, which I got in 2003, has been very easy to open from the beginning.

I am going to telephone New Graham and see what they have to say about the situation.
 
Other than what Nyef said (pushing the thumbstud upward parallel to the frame), the only other idea I might have would be that the pivot screw is tightened down too much. The Umnumzaan is different from a Sebenza in that it doesn't have a pivot bushing to prevent overtightening. The pivot assembly has to be screwed down, and then backed off a tiny bit. That's why the takedown kit has some Locktite included.

You might consider getting one of the $12 kits and experimenting for yourself. Michael at New Graham should be able to help you out in either case
 
If you push the lock bar to the position it's in when the blade is closed, does the blade move easily or is it tight ??? That's how I check the tension on the blade pivot screws on frame locks that have adjustable pivot screws like the umnumzaan and xm's. If the blade is snug, then you know you need to loosen the blade pivot bushing a smidgen/hair. Sometimes all it takes is like 1/8th of a turn to find that sweet spot.
 
Nyefmaker, it is rather tight, when I do what you said. Once again, given what I viewed on several youtube videos, the pivot bushing has been tightened too much.

Dallas, it seems to me that the knife should work properly right out of the box! Definitely a QC problem, as it seems that the mechanism was overly tightened, and then the locktite made it impossible to change.

Sadly, New Graham has none in stock, but they agreed to pay for return shipping and insurance. The knife is fantastic, but clearly is not working as it should.
 
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Mine came extremely tight. I opened it 3 or 400 times before it really started to get loose enough to move easy. The detent on mine is so strong that when overcoming it the knife usually travels all the way and locks open. Worth trying if you really like the knife. BTW, I got the last one in stock :)
 
Since my small sebenza never had this problem, I am completely dissatisfied with the purchase. The umnumzaan is on its way back to New Graham, and my opinion of CRK has dropped down to the bottom of the ladder.

There is no excuse for poor QC on a a knife costing $400!!!
 
merlinus said:
Since my small sebenza never had this problem, I am completely dissatisfied with the purchase. The umnumzaan is on its way back to New Graham, and my opinion of CRK has dropped down to the bottom of the ladder.

There is no excuse for poor QC on a a knife costing $400!!!
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How about send it to Chris Reeve instead? You paid for the service as well as the knife, so have the manufacturer fix it for you.
 
I agree, kipzroll, but I sent it back to New Graham. At least they offered to not only refund the $400 but pick up the return shipping and insurance. I doubt CRK would have done the same.

Also, I found the takedown kit to be a big joke. The plastic wrenches did not stay on the pivot screws long enough to use the allen wrenches to possibly loosen it, even with two of us trying.

I did, however, send a long email to CRK detailing my unfortunate experience. Hopefully they will respond.
 
I'm a recent new owner of a used Umnumzaan and I found the tooling to work just fine. Have a hard time understanding the two person approach in using the tooling. It did take me a few tries to understand the correct opening process when using the Zaan, but it has become very easy for me to open. Very sorry to hear about your experience, sounds like you gave up on it rather quickly. I find the Zaan to be a very fine knife and plan of buying a second one soon, hopefully with the new steel. As with all things, "everything is not for everybody", sorry it did not work out for you.
 
BRO said:
I'm a recent new owner of a used Umnumzaan and I found the tooling to work just fine. Have a hard time understanding the two person approach in using the tooling. It did take me a few tries to understand the correct opening process when using the Zaan, but it has become very easy for me to open. Very sorry to hear about your experience, sounds like you gave up on it rather quickly. I find the Zaan to be a very fine knife and plan of buying a second one soon, hopefully with the new steel. As with all things, "everything is not for everybody", sorry it did not work out for you.
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+2 I'd have sent mine back if I gave up on it right after I'd gotten. It's still not the most comfortable thing to open due to having to break in. The tolerances are just that tight that it takes a little time. As for CRK and "it being inexcusable for a 400 dollar knife", I was working in a shop one time and a 160K dollar dump truck came in that had a blown engine with under 300 miles on it. No company is going to be perfect everytime. CRK sure comes close though:)
 
FWIW, I spent an hour trying to loosen the pivot bushing by myself. Then I asked my partner to assist, in hopes that two hands would be better. After another half hour, she was just as frustrated.

As I stated, the plastic wrenches kept falling out of the pivot screws, and therefore inserting the allen wrenches was of no use. A much better system would have been if the plastic pins snapped into the four holes.

I may be somewhat lame when it comes to these kinds of tasks, but I am skilled enough to have a good living as a computer professional, including replacing various kinds of drives and boards, so I can afford CRK knives.

Maybe the breakdown kit was as flawed as the knife...

As for a break-in period, the folks at CRK, and the youtube videos I viewed, never mentioned any such thing!
 
merlinus said:
I agree, kipzroll, but I sent it back to New Graham. At least they offered to not only refund the $400 but pick up the return shipping and insurance. I doubt CRK would have done the same.

Also, I found the takedown kit to be a big joke. The plastic wrenches did not stay on the pivot screws long enough to use the allen wrenches to possibly loosen it, even with two of us trying.

I did, however, send a long email to CRK detailing my unfortunate experience. Hopefully they will respond.
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That's understandable. Shame you didn't have as good of an experience with it as you have had with your Sebenza. I'm sure that CRK will respond and provide some explanation.
 
Mine took about a week of playing with it constantly to finally loosen up. After that it flicks silky smooth as long as you push towards the pivot. It was pretty tough at first though. If you thought this knife was tough don't ever buy a Strider then.
 
I'm glad I bought the last one they had in stock. Wouldn't have wanted someone to get stock with another "faulty" Umnumzaan.
 
It's too bad that the Zaan didn't work out for you. When I received my first Zaan I wasn't impressed, so I sold it. After a few months I said to myself , give it another try. Well I sold it. For some reason months later it was still talking to me. So guess what?? I bought another and I absolutely love it. It is so freaking smooth.
I found the pivot wrench to be extremely simple and effortless to use on all 3 Zaans.
I only have one Zaan but have probably 12 various Sebenza's. The Sebenza get's my vote every time but I am finally very very very happy with the Zaan. It's possible you just had one that the tolerances were over the top.
Hopefully one day you will do as I did and give it another try. Till then get another Sebenza!!!!!!!!!!!!!!!
 
The same thing happened to my sebenza. I sent it back to the dealer and got a new one. It seems like CRK needs to step up the QC a little bit.
 
I'm a new Zaan owner and it is one of my favorite knives and it works as advertised so I'm sorry yours doesn't. On any frame lock, if you think it's hard to open, try opening them left handed which will eliminate the detent against the lockbar problem. If a "rightie" framelock is tight to open when done left handed, you probably have a genuinely tight knife for one reason or another.
 
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