Need help with drill and tap for pocket clips

Hairlesstwinkie

Hairlesstwinkie

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Feb 4, 2013
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I have a mini-skirmish that is tip down, but it would be perfect if they are tip up. Does anyone know the size of the drill and tap used by Benchmade?

I'm also looking to add a pocket clip to my Buck 110.

Links would be much appreciated!
 
I'd suggest calling Benchmade and asking. If that doesn't work, get yourself a set of screw identifier gauges from knifekits.com (search for "identifier" at their site). The plastic ones are fairly cheap and available in imperial and metric (I'd get both just to be safe).
 
Bump for an update. I went ahead and ordered the metal versions of the screw identifiers from knifekits for myself after posting this. I'd been looking at them for a long time, and I finally decided to squeeze the trigger. They are freaking awesome! Very thick and heavy. Cost me around $31 shipped for both (sae, metric). Well worth it. Worth their weight in gold, in fact, for the knife enthusiast. :thumbup:
 
Thank you for the helpful post! I have had a metal one of the SAE version for ages (think I bought it at a Sears Hardware) but have not found a metric version anywhere. I'm always trying to identify hardware and usually have to resort to dragging out my tap and die set and using the thread gauge from that and/or holding a tap up next to a bolt/screw. I do have a nice wooden boxed thread identifier that I bought from somewhere but I don't ever have it handy when I need it :/
 
Most pocket clip screws that I have run into are #2X56TPI. The tap drill would be about a #50 for deep hole and about #51 for a shallow hole. The shallower the hole, the more % of thread you want.
Get a micrometer or caliper to determine your screw diameter and a thread comb to determine the pitch.
 
N8N said:
Thank you for the helpful post! I have had a metal one of the SAE version for ages (think I bought it at a Sears Hardware) but have not found a metric version anywhere. I'm always trying to identify hardware and usually have to resort to dragging out my tap and die set and using the thread gauge from that and/or holding a tap up next to a bolt/screw. I do have a nice wooden boxed thread identifier that I bought from somewhere but I don't ever have it handy when I need it :/
Click to expand...
:thumbup::cool:
 
I would expect them to be metric, that's interesting. FYI, the inch size #2-56 and metric size 2.5mm x .45 are very close to interchangeable. The diameter of the inch screw is .086" and the metric is .098" so they are only different by the equivalent of a few sheets of paper. The thread pitch (distance thread to thread) is the same for both within .0001" (one ten-thousandth of an inch, or about 1/40 the thickness of a sheet of paper) so it's not possible to differentiate the threads with a thread gage of the type you hold up to the screw, it's better to use measured diameter in this case, or a screw-in gage. A #2-56 will screw into a 2.5mm x .45 nut but not vice versa. Depending on the precision they can sometimes, but it's not advisable, using them this way could result in stripped threads.
 
I just got my new Grip today; will get accurate measurements of the screws later.
 
OK, according to my good "Chestnut Tools" thread checker, the Benchmade threaded inserts are in fact 2-56 and not M2.5 - the M2.5 "screw" included does not thread into the Benchmade threaded insert. I removed one screw from the clip and it threads nicely into the 2-56 hole but very sloppily into the M2.5 hole. Diameter of screw measures .085".

You didn't ask, but I'll tell you anyway - UHL is 9/32" and it takes a T-6 Torx driver.

I tried to find an exact equivalent on McMaster-Carr and Fastenal for you but couldn't.

As an aside to any BKC employees reading this - I removed one screw from my clip and put it right back, honest :) No warranty-voiding here (yet, anyway.)
 
came back to this...

knifekits product # 4638 appears to be an acceptable screw replacement, longer than what BM uses though (when buying hardware for things I don't do often, I tend to buy long lengths and cut to fit, assuming stainless or brass. Saves having to purchase more later.)

McMaster-Carr product # 92395A111 looks like an acceptable insert for FRP scales

2-56 tap should be commonly available although you'll need a "bottoming tap" if you don't want to drill all the way through the bolsters of your 110...

if you need to shorten screws, I would drill and tap a hole through a piece of mild steel, insert the screw to be shortened, then file it flush to length. In my electrician's kit, one of the strippers has tapped holes that allow you to shorten common screws by shearing off the ends, but I think the smallest size is 6-32.

I have no experience drilling or tapping titanium (I believe that that is what the scales of a Mini-Skirmish are made from, yes?) so I'd search and also solicit opinions on that process.
 
Definitely #2-56 then. I thought everybody was switching to metric these days, guess not. On the titanium threading, it can be very difficult at larger diameters and thread depths, but it should be easy at this size. Make sure to use a sharp drill and new tap though, because if you don't the titanium may work harden and you will have a hell of a time. (Think snapped off tap in the hole). I would also tend to shy away from shearing screws to length with one of those electrician's plier sets, though you are unlikely to find one for a #2-56. That's the hack way of doing it, and you'll get a nasty thread on the end which will require further work anyways. Use a Dremel or die grinder with an abrasive cut-off wheel, a hacksaw or the file method described above if you don't have much to remove. Afterwards, chamfer lightly at 45° all the way around the end with a bench grinder, file, or what have you to remove any burrs and make the thread easier to start.

(Qualifications: 20+ years as a machinist).
 
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