ZT 301 speed safe removed?

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May 1, 2007
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I would like to remove the speed safe out of my ZT 301. I know how to get it out. I would like some tips or maybe a pic or two on how to drill a ball detent on the blade. I know there was some one here who did it but for the life of me I cannot find the thread. Thanks
 
I think someone did that by using a small carbide "ball" cutter on a Dremel, at the very end of the faint "arc marking" on the blade.
 
I did this with my Baby Boa. I used a drill press and a 1/8" straight-flute carbide bit.

I just placed the hole at the point where the detent-arc ended. Make sure to clamp the blade solidly.

I could have used a smaller bit, but functionally it works great. The edges of the hole are very sharp making for a strong detent. The blade doesn't flip like others I have, but that's more to do with the size and shape of the flipper and blade. The detent is plenty strong.

I can take some photos if you would like.
 
I did this with my Baby Boa. I used a drill press and a 1/8" straight-flute carbide bit.

I just placed the hole at the point where the detent-arc ended. Make sure to clamp the blade solidly.

I could have used a smaller bit, but functionally it works great. The edges of the hole are very sharp making for a strong detent. The blade doesn't flip like others I have, but that's more to do with the size and shape of the flipper and blade. The detent is plenty strong.

I can take some photos if you would like.

Yes please if I could see a pic of that. Thanks
 
Here it is:

3408151040_413facf2a4_o.jpg


As you can see, 1/8" is way too big. You have to make sure that the edge of the hole ends up in the right spot, (at the end of the arc), or you'll get some wiggle. There is a bit of wiggle on this one, but it's only a few thousandths of an inch.

The bit is straight-flute carbide. I ordered it from MSC. These bits are brittle, so make sure you have a solid setup. A standard drill-bit will not work.

If you wanted a softer detent, you could chamfer the hole. As it is, it works well for a flipper.

Phillip
 
Maybe you are talking about me, I removed the Speedsafe from my 0301 & drilled a detent, here are the links:

http://www.coltelleriacollini.it/community4/modules.php?name=Forums&file=viewtopic&t=8015&start=0

(original topic with full review, sorry all Italian)

http://www.bladeforums.com/forums/showthread.php?t=616055

...Oh my God :eek: !!!

The Kershaw forum is closed:(, I hope that is only momentary, I am a recent customer of Kershaw and quickly added K. to the list of my favourite manufactures (after the 0301 I also ordered recently a Bradley-Kershaw Kimura, it will arrive in about a week :D ); I have found that forum really helpful to gain news on the models and a great community:thumbup:

For the detent-speedsafe
Removing the speedsafe is really easy:thumbup:, but if you remove it you will have extremely low blade retention, I drilled a detent myself, using a free hand electric drill, it is really hard to find the exact spot you need to drill & you will lose the warranty for the knife, so it is a risky work.
I used these Dremel tools to drill:
http://www.dremeleurope.com/dremelocs-it/Product.jsp;jsessionid=A15DD1FAB39184562D97056481CAA9E2?&ccat_id=485&prod_id=116
http://www.dremeleurope.com/dremelocs-it/Product.jsp;jsessionid=A15DD1FAB39184562D97056481CAA9E2?&ccat_id=485&prod_id=372

And I often used water to keep the blade cool & not damage the heat treat; also worked slowly.
To see the exact spot where you have to drill, I suggest to put a little bit of white ink to the ball in the liner & see where it stops when the blade is closed (it is hard to find this spot, it's the hardest part of the job).
My detent works good & gives a good feeling, with about 50% more blade retention, but it is a home made detent, it is far inferior to a well made detent made by the manufacture; but I am happy with the result & I love my 0301 (great knife), especially now with my detent.

In conclusion I suggest to you to think twice before attempt to drill the detent, because it is really hard & you risk to damage or ruin the knife & you will lose the warranty.
If you decide to drill the detent I wish you luck ;)


P.S.
Kerhaw please come back & keep up the good work! ;)
 
Glad to be of help.

I highly recommend you use a drill press. This will allow you to fine-tune the position before permanently modifying your knife. I run the bit slow, (about 300 rpm), and use a fairly high feed rate to reduce chatter. (Maybe a machinist will chime in here.) Cutting lubricant is a good idea, but flood coolant is unnecessary because the speed is so low.

Felix's abrasive bits are probably a good idea if you will be opening the knife with thumb studs. They will round the edges a bit and provide a softer detent (they're also cheaper). The straight-flute bit makes a very sharp hole, causing a lot of resistance. This is great for a flipper, (it loads the flipper a lot), but makes opening via the thumb studs a bit stiff.

Phillip
 
High speed steel bits like that are too soft to cut hardened (blade) steel. They just skate (I've tried).

You need carbide to cut hardened steel. Carbide bits are expensive and fragile, but they're the only thing that will work (except abrasives).

Abrasives burrs basically grind a hole into the material. They leave a cruder hole, but they work on other material like stone. They are generally less expensive than solid carbide.

Here's a good carbide bit: http://www1.mscdirect.com/CGI/NNSRIT?PMPXNO=17533199&PMT4NO=0

Phillip
 
I agree with firebert a drill press will make the job a lot easier.

High speed steel bits like that are too soft to cut hardened (blade) steel. They just skate (I've tried).

:thumbup: Absolutely same here, I' ve tried to drill a hole in an italian fixed blade in N690 for paracord grip without success using that type of bits, they skate:thumbdn:
Instead the dremel diamond bits work really well, I also drilled a hole in my Cold Steel GI tanto for the lanyard (old version did not have one), using them.
You are also right for water, I use water also as a lubricant to drill easier, the temperature is not so high, so water is only a precaution for heat treat.
 
Hey Firebert, have you ever tried a cobalt bit? I used one to drill through a steel pocket clip when all my other bits, high speed, just spun on it. These clips are hardened to spring steel levels, but I have no idea of the HRC of this, only that the cobalt bit drilled through in about 5 seconds. The cobalt bits are 2 to 3 times more expensive than standard high speed bits, but less than a carbide bit.
 
I have cobalt bits. I'm not sure if that's the one I tried. I can't think of any blades I'm willing to try it on. Pocket clips are softer than blade steel.

If you had a torch, it might be possible to spot-anneal the blade too. It'd be tricky, though.

Phillip

p.s. Was that the clip for the MUDD, by chance?
 
I have used cobalt drills (I was thinking that you had talked about cobalt bits), on N690 they skate, they don' t remove steel, at least on hardened steel, but maybe on a drill press they will work better, on hand free drill, they are useless on hardened steel.
 
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