quick release for jump/break cue question

BHQ

BHQ

we'll miss you
Silver Member
can i take a 3/8x10 pin and turn off the first few threads to make a quicker release? like the pins on bunjees.
i looked on atlas. did not see any quick release pins and inserts.
thanks, brent
 
It can be done. I was playing around to see if I could do one. The 14 TPI would be better as the threads are coarser, but it can be done. Can't tell from the picture, but this pin polished up to a mirror finish even. I center drilled It, and turned It down while between centers, so it's dead on. Only problem is it's already been done, I eventually want to do one noone has done yet. Seems like we were discussing this before, and mike suggested this alternative, so I decided to try it for fun. The unilocks are already made that way, and due to their shank design, are easy to install using a small boring bar.

Good luck with it.

Greg
 

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stix4sale said:
can i take a 3/8x10 pin and turn off the first few threads to make a quicker release? like the pins on bunjees.
i looked on atlas. did not see any quick release pins and inserts.
thanks, brent
Click to expand...

I agree with Murray but I'll elaborate further. I think the main reason to use the 5/16 series threads in a quick-release joint is because they use a brass insert. The brass is strong enough that you can get away with the accepted minimum thread length (where thread length = thread diameter).

If you were to cut the thread length on a 3/8-10, the pin would be fine. However, I think you would be putting the wood threads in the shaft under too much stress, inviting disaster.

You can get around the problem by using a linen phenolic insert in the shaft & tapping it. The material is strong enough that it will hold up fine. Instead of removing the threads from the pin, I bore out the first 1/2" of the phenolic insert. This still leaves plenty of strong thread engagement yet assembles quickly.

I also relieve the first 1/2" of threads in my 3/8-10 JPs as a quick-release feature. It's safe to do this on a wood JP since you're not really torquing it down nor subjecting it to any stress from play.
 
dzcues said:
I agree with Murray but I'll elaborate further. I think the main reason to use the 5/16 series threads in a quick-release joint is because they use a brass insert. The brass is strong enough that you can get away with the accepted minimum thread length (where thread length = thread diameter).

If you were to cut the thread length on a 3/8-10, the pin would be fine. However, I think you would be putting the wood threads in the shaft under too much stress, inviting disaster.

You can get around the problem by using a linen phenolic insert in the shaft & tapping it. The material is strong enough that it will hold up fine. Instead of removing the threads from the pin, I bore out the first 1/2" of the phenolic insert. This still leaves plenty of strong thread engagement yet assembles quickly.

I also relieve the first 1/2" of threads in my 3/8-10 JPs as a quick-release feature. It's safe to do this on a wood JP since you're not really torquing it down nor subjecting it to any stress from play.
Click to expand...

bob, i like the idea of the brass insert to strenthen joint also. thanks for confirming that thought. brent
 
I use a 3/8X16 quick release for my jump breaks, It goes into a brass insert.
I also use a 3/8X10 but I use a phenolic insert.
 
Michael Webb said:
I use a 3/8X16 quick release for my jump breaks, It goes into a brass insert.
I also use a 3/8X10 but I use a phenolic insert.
Click to expand...
Mike,

How far down do you turn (or grind) the threads off on the 3/8 16?

Thanks,

Jon
 
I was going to try that next. I have some 3/8 SS in rod form. I'm not sure what size mike grinds them, but on the 5/16, I just took It down to the dia of the bottom of the threads. The insert seems to be key to having a tight fit on them. I would hand make those also, so you can get a tight fit. Ya know a full tapered pin would be pretty cool with a insert to match :cool: Has anyone tried that yet? Greg
 
You can use the 5/16 pin, just turn the front shank of the pin, not the insert to clear the insert with a comfortable fit. The brass inserts I make for the 3/8X16. I use a solid shank @.280 for 1 inch and I leave approx. 1/2 inch of threads. I taper the first two threads. The O.D. of the brass insert in threaded all the way, I hate that shoulder B.S.
Uni loc is a good invention EXCEPT, you can't turn the insert side between centers to face correctly because it starts right away with threads, instead of a concave first. I still can't believe that part was overlooked.
Maybe it's me!
 
Michael Webb said:
You can use the 5/16 pin, just turn the front shank of the pin, not the insert to clear the insert with a comfortable fit. The brass inserts I make for the 3/8X16. I use a solid shank @.280 for 1 inch and I leave approx. 1/2 inch of threads. I taper the first two threads. The O.D. of the brass insert in threaded all the way, I hate that shoulder B.S.
Uni loc is a good invention EXCEPT, you can't turn the insert side between centers to face correctly because it starts right away with threads, instead of a concave first. I still can't believe that part was overlooked.
Maybe it's me!
Click to expand...


I noticed that about them, the front of the inserts are tapered, but the bottom is'nt. I like the compression feeling fit to the joint, and the way they pop if you pull them apart quicky, seems like pretty close tolerences, but as far as the taper goes Even the non-self aligning inserts usually have both sides tapered, so not sure why not Myself either.

On the shoulder, I know what you are saying, pretty much depending on that small patch of bottom threads to be perfect, and hold. I do the bore for the shoulder with a small handmade looking carbide ID tool I picked up in a lot of drills and tool bits, and use It as a mini boring bar for them. It stays really sharp. I can take really small passes with It, and bump the fit for the shoulder in as tight or loose as I want to, and it's hard to take too much off with it, so It's perfect. I can get a really snug fit without it locking the insert during installation, or blowing the shaft out, and since it's bored I know I have a straight hole to align It properly. I drill the bottom to size, ream & tap afterwards, so what little threads are there, are all good, and grip the insert well. It seems to be working pretty well for me, but only time will tell for sure.

Apprietiate all the tips on the pins Mike, having fun with It. I am going to try the 3/8 next, Maybe a 5/16-14, then would like to practice cutting My own thread after, out of brass to start with probably, then on to ss.


Thanks
Greg
 
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