drilling a detent hole for a kershaw knockout

johnnytoxin

johnnytoxin

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I've got a Kershaw knockout I want to convert to a manual folder. Problem is the torsion bar for the assist mechanism is the detent so once I remove it there is nothing to keep the knife closed. So I must drill a hole in the blade for the detent ball to rest in when the knife is closed. I believe the ball is 1/16 so what size drill bit should I use? Also anyone have tips for marking the position of the hole? And yes I am aware that this will void the warranty. Thanks.
 
Ya I've seen the video. He doesn't say whether to make the hole smaller, the same, or slightly larger than the detent ball. That's where I am unsure.....
 
From samples I have around (Enlans, Sanrenmus, Resilience), it seems to be slightly smaller than the detent ball diameter where it (ball) intersect with the lockbar. That way, the ball will not be totally dipping into the hole.

Never done that, just looking at how those are factory made.
 
The hole can be bigger than the detent ball, just make sure the ball barely falls into the edge of hole you're drilling. If you drill right at the point where the detent arc stops, your blade will be loose in the handle when closed, so start your hole a little bit past it.
 
Does anyone know where I can get a 1/16 drill bit for drilling hardened steel?
 
johnnytoxin said:
Does anyone know where I can get a 1/16 drill bit for drilling hardened steel?
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Get an MSC Industrial carbide spade drill or a 2 flute type carbide. Stay away from the twist drill. You can buy the two flute at Jantz Supply also I think and its a good quality drill. You don't want a 1/6" though. Just find a number 53 carbide from the same place and it is the same size as the hole for the detent in the lock. Take the detent out by sticking a number 53 in upside down or if you prefer go down a size and use that but push the ball out using your drill press. Just pop it into a shallow recess you scoop out of a board and press it out. Put the knife back together but without the lock side scale and close the blade. Just quickly pop the carbide through the hole in the lock and mark the blade with the carbide. Just mark it don't really drill it just give youself a bump scratch dimple to see. Then take the blade back out and just dimple it. Don't go in deep just a very shallow 'starter' dish out and it is shallow, don't go too deep doing it this way. Just a small dimple and hopefully it will remain just right when you hold the blade to mark it that way. Ideally I like to bump the notch or dimple so the ball catches on the rim of the hole if that makes sense. This method your ball will fall straight into the hole. If you go too deep it will sometimes fit too much and it can be hard to free to get the blade started to open and it can also close and catch but the blade may tip may be able to lift a bit up and down so that is why you want just a shallow bump doing it this way.

After you dimple the blade now take the lock back out and use the lock side washer as a gauge to set the depth of the ball. Simply press the ball back down using either your drill press with a drill in upside down or an arbor press or you can tap it with a small ball peen and flat end punch with washer around the ball. The ball will seat and stand up to the height of the washer this way and you should be good to go unless you f*%* it up! :D

STR
 
Damn, that's some good info from a pro right there. Thanks STR. One problem though. The hole that holds the detent ball is not drilled all the way through.
 
Hey I stumbled across this thread and have the same problem! I am glad I'm not the only one that wants to make this a manual flipper. I'm calling kershaw tomorrow and asking what size ball I need.
 
Gmrpnk21 said:
Hey I stumbled across this thread and have the same problem! I am glad I'm not the only one that wants to make this a manual flipper. I'm calling kershaw tomorrow and asking what size ball I need.
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THe knife should have a detent ball. It would be really rough to open if it didn't. The knife doesn't have a hole for the ball though.
 
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