31 Screws Keep Backing Out

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brownshoe said:
Sebenzas are not supposed to need loktite by design. If it needs loktite to stay together, CRK screwed up. Chris Reeve was proud of the fact the Sebenza didn't need screw glue to keep it together...it's kind of a tool and die maker thing.
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Easier to go right to the source. Note that while I’ve only quoted a small portion it’s well worth a read. It could have been written yesterday instead of ten years ago.

Chris Reeve Knives said:
All screws should be snugly tightened down onto the pins – there is no need for Loctite, nor is it necessary to super-torque the screws down. (Exception - see comments on Umnumzaan pivot.)

· With the Umnumzaan, Loctite is necessary in the pivot assembly. The threads in this assembly are machined to very close tolerance; the drop of Loctite gives additional rigidity. It also prevents the pivot from backing off. Loctite is an accepted engineering screw retention substance used in a wide variety of industrial applications including medical, electronics, automotive and aerospace. We do not “glue” our knives together. Extensive thought went into all aspects of this pivot assembly – it did not happen by accident.
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Nice quote. Also shows the difference in how Chris treated customers compared to Tim&Ann LLC does.
 
Same thing was happening to my 31. I just switched the two body screws and it's been fine since.
 
I can't help feeling that if thread locker is required to keep a screw from backing out, that's a damaged or defective part or poor design. I like the Inkosi so much I'm able to overlook this aspect of the knife, and maybe if I tried a 31 I'd feel the same, but I think it would bother me. Not one of the many Sebenzas I've owned from every generation since '93 (no 31 yet), has had that issue.
 
I also had a minor issue with the pivot screw backing out after I had disassembled/reassembled my 31. Turned out a little of the fluorinated got into the screw as I pushed it through after inserting the blade. I haven't had an issues since after cleaning out that bit of grease in the screw.

One thing that seems pretty common with the 31 is the heavy lockbar tension. The lockbar on mine also would go well past touching the other scale during disassembly. I don't feel the need to try and lighten up that tension as the action still feels good, but I do find it could have quite a bit less tension and perform just as well or better.
 
I’ve been away from (buying) knives for a while, but still carry a knife every day. I have 3 wonderful CRKs, but none of them are my daily carries (I did carry a small Insingo Inkosi for a year). I ordered a small black micarta 31 at launch but bad timing when CRK contacted me to confirm I still wanted it, so did not get. Now for the past week have looked for the same knife on line and finally found. I decided to come back to these forums for one more peak that early issues with the 31 have been resolved. Based on this thread, not sure they are. I think I’ll keep my money in my pocket for a bit longer. I’m sure at some point I’ll give in. The input here is valuable.
 
My large 31 has a bday of 8/17/20 and the two lock bar screws both had the purple loctite on them from the factory, plus it came with a small tube of it like the Inkosi.

I actually cleaned it off and haven’t had an issue with them backing out or loosening. Also, there’s no blade play or “lock rock“. The “lock rock” thing intrigued me since I read so much about it but my knife needs so much force to make it happen, it’s not even worth worrying about. A little loctite doesn’t bother me one bit if I need it, hell, I ride a Harley so I’m used to bolts and stuff loosening up over time lol.
 
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Jsega51 said:
My large 31 has a bday of 8/17/20 and the two lock bar screws both had the purple loctite on them from the factory, plus it came with a small tube of it like the Inkosi.

I actually cleaned it off and haven’t had an issue with them backing out or loosening. Also, there’s no blade play or “lock rock“. The “lock rock” thing intrigued me since I read so much about it but my knife needs so much force to make it happen, it’s not even worth worrying about. A little loctite doesn’t bother me one bit if I need it, hell, I ride a Harley so I’m used to bolts and stuff loosening up over time lol.
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I think it's important to differentiate between the terms "lock rock" and "lock flex".

Rock is when there is space between the blade surface and the lockbar when the folder is completely open, the blade can wiggle vertically as it contacts the lockbar on one end, then contacts the stop pin on the other end. Flex is when there is no spaces between the lockbar and the blade, however, applying force to the spine in that locked position may create some flex in the lockbar. This flex is transient and temporary. Once the pressure is released, the lockbar returns to its normal shape and the blade returns to the fully locked position, being held in place by the stop pin and the lockbar.
 
Alsharif Alsharif right, that’s why I put “lock rock” in quotes. That’s what the issue was named from the very beginning, but yes, in the later comments it was clarified what was actually happening. The name “lock rock“ stuck though.

Mine will do it, but it’s nothing that I’d ever find happening in my normal carry and use of the knife. I’ve never laid one on the table and forced down on the blade spine, until the other day.
 
Alsharif said:
I think it's important to differentiate between the terms "lock rock" and "lock flex".

Rock is when there is space between the blade surface and the lockbar when the folder is completely open, the blade can wiggle vertically as it contacts the lockbar on one end, then contacts the stop pin on the other end. Flex is when there is no spaces between the lockbar and the blade, however, applying force to the spine in that locked position may create some flex in the lockbar. This flex is transient and temporary. Once the pressure is released, the lockbar returns to its normal shape and the blade returns to the fully locked position, being held in place by the stop pin and the lockbar.
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Jsega51 said:
Alsharif Alsharif right, that’s why I put “lock rock” in quotes. That’s what the issue was named from the very beginning, but yes, in the later comments it was clarified what was actually happening. The name “lock rock“ stuck though.

Mine will do it, but it’s nothing that I’d ever find happening in my normal carry and use of the knife. I’ve never laid one on the table and forced down on the blade spine, until the other day.
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Lock rock is when the blade tang can be “clicked” between the stop pin. The lockface generally makes contact with the blade tang during lock rock. A lockbar that doesnt touch the tang of the blade is sloppy workmanship. Lol. :D

ETA: It will be a combination of both. Generally in my experience though, its a weak lockbar allowing it to slip and have the blade come off the stop pin.
 
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My large 31 with 8/17/20 DOB arrived with a small tube of locktite (CRK branded, just like the tube of grease), included in the baggie with the grease and wrench.

There are a lot of posts here saying a Sebenza should never need locktite... why would it be included then?

Is my packaging a unicorn?
 
TRfromMT said:
My large 31 with 8/17/20 DOB arrived with a small tube of locktite (CRK branded, just like the tube of grease), included in the baggie with the grease and wrench.

There are a lot of posts here saying a Sebenza should never need locktite... why would it be included then?

Is my packaging a unicorn?
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My post just a few above yours. Same birthdate! Twinning!!!


Jsega51 said:
My large 31 has a bday of 8/17/20 and the two lock bar screws both had the purple loctite on them from the factory, plus it came with a small tube of it like the Inkosi.

I actually cleaned it off and haven’t had an issue with them backing out or loosening. A little loctite doesn’t bother me one bit if I need it, hell, I ride a Harley so I’m used to bolts and stuff loosening up over time lol.
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The fact that they are including the thread locker now makes me think they've been getting a lot of complaints about it. FWIW, I haven't had any more problems with my screws backing out and the last time I took it apart they made the pop when breaking loose.
 
TRfromMT said:
My large 31 with 8/17/20 DOB arrived with a small tube of locktite (CRK branded, just like the tube of grease), included in the baggie with the grease and wrench.

There are a lot of posts here saying a Sebenza should never need locktite... why would it be included then?

Is my packaging a unicorn?
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Must be included because the Sebenza 31 is a Ann/Tim knife not a Chris knife.
 
TRfromMT said:
My large 31 with 8/17/20 DOB arrived with a small tube of locktite (CRK branded, just like the tube of grease), included in the baggie with the grease and wrench.

There are a lot of posts here saying a Sebenza should never need locktite... why would it be included then?

Is my packaging a unicorn?
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The reason for not needing locktite is explained in post 41 by CRK themselves. They just started including locktite since all the complaints about the 31 screws backing out came to light
 
brownshoe said:
Must be included because the Sebenza 31 is a Ann/Tim knife not a Chris knife.
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Your childish behavior has never wavered in the past decade I've been visiting this forum.

Alsharif said:
What’s that supposed to mean?
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It takes an order of magnitude more effort to refute bullshit than it does to create it. Leave the fools with the childish outbursts alone and you'll be happier for it.
 
brownshoe said:
Chris Reeve designed the Sebenza to be field seviceable with one common wrench and no loktite. The company is now run by two relatives Tim/Ann.
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It’s still field serviceable. Loctite doesn’t prevent it from coming apart. Do you have a 31 and have you experienced any screws coming out? If you’ve only read it on the forum, that’s not good enough since I’ve seen posts where people have had screws on the 21 work loose over time also. Funny that in those threads I don’t see you ripping the company though...
 
I have a 21 for many years, it doesn't need loktite. Needing loktite means you can not put it back together with only one wrench, like a 21, with the 31 you need glue too. Chris was proud of the Sebenza being designed to not need glue. He used to post here.
 
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