"Weakening" a linerlock detent?

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Dec 4, 2005
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I have a knife that has a detent that is too strong and my calloused (spelling?) thumbtip is getting torn up trying to open it by thumbstud. I have thought about slightly sanding down the ball that goes in the detent to loosen it up but one problem I think of running into is how smooth it will be afterwards. I'm sure that smoothness of the ball ensures easier disengagement of the detent and I don't want to make it worse. I have tried repeatedly opening and closing the knife just past breakaway to loosen it up but still no luck. Any suggestions? Thanks in advance!
 
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Oct 30, 2005
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Which knife is it?

Does it have an actual teeny bearing, or does it have a punched rise in the liner?

I solved a difficult liner lock problem by using a cone shaped machinist slip stone to "chamfer” the hole in the blade (got lucky on finding one that small). I’ve also used the “wear it in” method (over a couple of days).
 
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Jan 12, 2005
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TF,

Sounds just like my brilliant Buck Mayo Cutback. Hard to start the opening process. The frame lock works to softly lock it closed as well as lock it hard opened.

I switched to opening it by starting with the flat surface of the tip of my thumbnail and, when the blade starts to open, roll to the fleshy tip of my thumb to complete the arc. Now the thumbstud just chews up my thumbnail.

Not the fix you have in mind but you might try it prior to altering the lock. If it doesn't work for you then you can break both my legs and I won't squawk.

Best,

oregon
 
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Contact the manufacturer!

If you remove too much steel, you'll be stuck with a knife that won't lock.

The manu. should be able to do it for free, minus shipping charges.
 
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orthogonal1 said:
Which knife is it?

Does it have an actual teeny bearing, or does it have a punched rise in the liner?

Its a Cold Steel (yeah I know) Tilite with zytel handle. It has a punched rise in the liner but the main problem is the thumbstud located too close to the handle when closed and it sits very flush also. I've thought about trying to contour the handle around the thumbstud to get more thumbtip in there but I will most likely ruin the handle scale doing that. You have a good idea with chamfering the hole, that seems the beast way to go.
(don't know how to multiple quote) so,
Deadhead Archer, definately a good idea not to remove too much metal. I can picture myself dissassembling and reassembling the knife many times to avoid doing that.
Thanks everyone for the good suggestions
 

STR

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I'd try to drill out the hole in the blade that the detent ball falls into just a tiny bit with a small diamond burr. A round one just a tad bigger than the hole itself to round it out some so it does not catch and hold so much. You will most likely have to take the blade out to do it.

If it is still stiff after that first try above. For the detent: What I normally do is take the knife apart and use the washer from the lock side. Sit it right over the ball on the lock so it circles it. Then use a flat punch and push down on the ball making the lock sit flat on an anvil or other hard clean surface. Take a light weight ball peen and just tap the punch that is sitting so it is centered on the ball and over the washer. It will push the ball in so that it is sticking up exactly the same height as the washer is thick.

If it still doesn't make it easier try a slighly longer thumb stud. You can make your own from a pivot pin .5 or .4 in length and cut it to how short or long you need it using a cut off disc and dremmel.
 
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Wow thanks STR, yet another great idea. By the way you do great work from what I've seen in many searches on this site before I started posting.:thumbup: :thumbup:
 

STR

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No problem. Thanks for the compliments. I hope you get it ironed out. When and if you try that trick on the hole in the blade for the detent just focus on the top rim and don't go in real deep or you may change the dynamics of the detent function. You want it to still keep the knife from opening by gravity. What you are aiming for is to allow the ball to roll off and out of it a little easier. It won't take much to do that. Take baby steps.

Seriously though the thumb stud could be a larger part of the issue. Get you a pivot barrel from knife kits that uses a 2-56 size screw and make your own. I use those over the store bought thumb studs for the very reason you are complaining about. For one thing they are smooth and easy on the thumb. I have to most always take off the knurls on the store bought ones just because they dig into your thumb over time and they can even make it raw and bleeding if you are building a knife and testing with one so it gets used a lot or if you just happen to have a day when you are opening and closing your knife a lot.

STR
 
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Oct 30, 2005
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I had the Ti-Lite with titanium handle.

The lock was initially stiff as you mention. It eventually loosened up a bit. Then too much.

The problem wasn't keeping it closed, it was locking open.

Also, you can flip this knife open by catching it on some cloth (I used my pant leg). Or, you can flip it open using the ricosso (spelling?) instead of the thumb stud with your thumb. I took to using my thumb on the ricosso.
 
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