Question about eccentric pivot pin.

Klesk

Klesk

Gold Member
Joined
Jan 5, 2003
Messages
1,105
I've heard eccentric pivots mentioned somewhere in the Forums, but I'm not sure what it is. I've been around knives a long time, but I haven't really needed to disassemble very many. Recently, I put a Buck/Strider back together - the once smooth and easy opening knife would open only with considerable force and the liner would not drop in properly. If I backed the pivot out enough so that the knife opened easily, the blade rocked back and forth quite a bit. Finally, after disassembling and reassembling it several times, the knife "magically" worked again, good as new.

I have a few questions:

1. What is an eccentric pivot pin?
2. Is that what I ran into on the Buck/Strider?
3. How do I properly reassemble a knife with an eccentric pivot?

Thanks again for all the help/info. :)
 
Hope this helps:
-An eccentric pivot is one that allows for adjustment of the blade tang in relation to a liner/frame lock bar. This in part helps to take care of any vertical play problems.
-To my knowledge, the only company currently using such a pivot is Spyderco.
-They are adjustable, however since Spyderco advises allowing the company to fine tune the knife, I'm not going to post directions.
-You would notice if you had an eccentric pivot as part of the lug is polygonal.
-Sometimes a knife just needs to break in, I know my Strider did. At any rate, I'm glad it is working better for you.

Matt
 
The eccentric pivot pin is a Spyderco design feature only on higher end liner locks. It allows you to ajdust the pivot pin in a manner that moves the blade and tang backwards and forwards to provide an adjustable lock position on a liner lock. For example, when you move the blade back a hair, you lockup closer to the liner side and adjust for wear on the liner. It works great and despite what the company tells you is user adjustable if you are mechanically savvy. You don't have to disassemble the knife to adjust. I've adjusted a Lum with great success. If you are interested in details, do a search on the Spyderco subforum, there have been very good directions posted.
 
Thanks, Jazzman and brownshoe, I really appreciate the information. I'm still in the dark, though, about what happened to my Buck/Strider. It opened very smoothly and almost too easily when new; then, after disassembly and reassembly, the action was horrible. With the pivot tension adjusted normally (the way I would adjust it on any knife), the blade would not open without exerting an unacceptably high amount of force. Also, the liner would not fully engage the blade tang, as it did before disassembly.

From the information supplied, it sounds like the Buck/Strider uses an eccentric pivot. Can anyone confirm this?
 
Once again, I believe that the eccentric pivot is a design created and used ONLY by Spyderco. The Buck instead uses two screws to control pivot tension (at least mine did). I don't know what happened to your knife, but I'm about 99.9 % positive that it wasn't the result of an eccentric pivot.
Matt
 
I no longer have the knives however, Benchmade had eccentric sleeves in the model 612 Crawford series, and the identical model made for Abel Fly Fishing products in CA.

The Abel blade had a disk and not the stud for opening the blade. The newest Abel knife is not made by Benchmade,,,,the eccentric sleeve construction appears to be identical.

The very early issue Benchmade knife had instructions with details on how to correctly adjust the sleeve.

Today Benchmade is not supporting owner/user adjustment.

Regards,
FK
 
With the pivot tension adjusted normally (the way I would adjust it on any knife), the blade would not open without exerting an unacceptably high amount of force. Also, the liner would not fully engage the blade tang, as it did before disassembly.
Click to expand...

If the liner would not fully engage the blade tang it sounds like you tightened the pivot screw too tight. On some knives I've found there is a compromise - either a slight amount of blade play, or the knife doesn't open worth a sh!t. I think on some knives, that's just the way it is.

On most of my knives, the blade opens fine and there is no play, but on a few it's either or. I'd prefer the blade to come out easily and have a little wiggle, instead of having a rock solid lockup and a gritty, forceful opening. My Buck Strider opened nicely, but after I did a little *ahem* chopping with it (ok, ok, I know you're not supposed to chop with a folder!) the lock went all the way across. It was a simple solution - I got in touch with Buck and sent it in. They sent it back adjusted to where the liner engaged at the far left side, the pivot was oiled or something 'cause it opened like butta!, and the blade was sharpened to "hair scaring" sharpness.

Long story short, if you aren't happy, send it in to Buck! The gentleman I got in touch with is Joe Houser. I think you can contact him using Buck's forum here in the Makers / Mfgs section. Buck is one hell of a great knife company. They honestly care, and they take excellent care of their customers.
 
You must log in or register to reply here.
Back
Top