Reducing joint pin threads

SSDiver2112

SSDiver2112

Escott Cues
I had a guy ask me if this was possible. His cue has a 5/16-18 joint pin. He wanted to know if the first few threads could be removed just down to the pin thus reducing the turns needed to assemble/disassemble.

Would the joint still be stable and secure enough?
 
So there was a reply asking me what I thought, but was deleted I guess.
I asked because I am still in the early stages of learning and understand the severity of messing with the joint threads. I'll try to answer anyway.

Being that there are joint pins out there like the Uni-Loc I see how on a surface level the logic seems possible.
Leaving enough threads should still lock the faces together for a solid connection.
Does reducing the number of threads proportionally reduce the integrity of the joint?
Is it more likely to loosen during play?
 
If you reduce to the diameter to being a close slide fit, it will not reduce the integrity of the pin at all. If you make the front too small in diameter, it may as well not be there as it will not have any support. Most threads, are supported by the vee formation or the effective thread pitch diameter. Seldom is a thread form supported on the minor or the major of the thread form. If the 5/16-18 is loose on the thread OD, or is loose on the thread ID , then reducing the front and expecting that section to be supportive is delusional. However, the reduced diameter will act as a guide to make it easier to align. Threads only needs to be as long as a standard nut to be fully effective in joining the two haves of the cue together.
 
sos911 said:
Just a quick question.... how painful is it just to screw them together? .. it literally takes seconds
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I agree that it is just a few more seconds and shouldn't be that big of a deal. He asked me and it got me thinking if it was possible and what the cons were. If it would still function properly, then why not if it makes him happier with his extra seconds.
 
conetip said:
If you reduce to the diameter to being a close slide fit, it will not reduce the integrity of the pin at all. If you make the front too small in diameter, it may as well not be there as it will not have any support. Most threads, are supported by the vee formation or the effective thread pitch diameter. Seldom is a thread form supported on the minor or the major of the thread form. If the 5/16-18 is loose on the thread OD, or is loose on the thread ID , then reducing the front and expecting that section to be supportive is delusional. However, the reduced diameter will act as a guide to make it easier to align. Threads only needs to be as long as a standard nut to be fully effective in joining the two haves of the cue together.
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Thank you for the help. That was my general thinking. I wanted to make sure I wasn't missing something.
 
Steel to steel threads tightened with tools have a general design based on threads length of about 1.5x diameter. That would equate to about 0.5in on a 5/16 screw.

Also in steel, a vee thread is fully loaded in seven threads...again about .5in on a -16tpi.

Now, you are into brass and not using wrenches. You could likely make three threads work.

I have a 3/8-10 that I did exactly what your customer is asking, I have about 6 threads steel into maple. It's fine.
 
SSDiver2112 said:
I had a guy ask me if this was possible. His cue has a 5/16-18 joint pin. He wanted to know if the first few threads could be removed just down to the pin thus reducing the turns needed to assemble/disassemble.

Would the joint still be stable and secure enough?
Click to expand...
I've done this a number of times. I've seen no problems with removing the amount of threads you are talking about on a 5/16-18 pin.

Alan
 
That is why we have Uniloc joint pins- I think- Dale Perry used them on some of his pre- Ebay cues- I have one- they work great if you need a few extra seconds in your day- however, actually cutting existing joint pins to save a few turns seems like one of the questions that is keeping me from going on this site more often recently:):):)
 
whammo57 said:
how ridiculous....... what is he going to do with the extra 7 seconds of his life????

Kim
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Well let's see: 7 sec - on and off would be 14 sec. Playing 5 times a week is 70 sec. So that's an hour savings every year. 2 hours with a breaker and 3 hours a year if he puts his girlfriend's together. lol
 
Something to think about - if this is a Huebler cue (any cue I suppose) with nylon insert I wouldn't do it. I simply wouldn't trust that the softer material would hold well over a long period of time.

Steel/brass - probably wouldn't be an issue but I would defer to others with more experience than me.
 
SSDiver2112 said:
Well let's see: 7 sec - on and off would be 14 sec. Playing 5 times a week is 70 sec. So that's an hour savings every year. 2 hours with a breaker and 3 hours a year if he puts his girlfriend's together. lol
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if you would have said..... 3 extra hours with his girl friend............ I could have agreed............. but NO
 
Whether you reduce a portion of the screw or bore the insert, your first concern should be whether you can do it accurately!
 
Mali was one of the first I know of faced with this situation. They decided to have thier brass inserts made with approximately a 5/8" deep counter bore for thier 5/16x14 joints.
 
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