I have 2 cues with 3/8 x 10 pins. One is a standard McDermott and one has an aluminum pin. Shafts are interchangeable but the female joint protectors are not. They fit fine on the McDermott but are very, very tight on the aluminum pin.I also have a Sugartree shaft that fits both. Any thoughts???
joint pin question
- Thread starter luke
- Start date
There's more than one 3/8-10 pin.........
http://dzcues.com/modified-pin.html
http://dzcues.com/modified-pin.html
They need a tap run thru them . Jim
The 'major-dia' is the same on both pins, 3/8".
The 'minor-dia' is probably what's tight
Retapping won't open the major any larger nor would it have to.
Run a 5/16" drill to depth in the J/B and it should fit.
The same tap is used for both pins, V-minor and Flat-minor.
What changes is the tap/drill used.
HTHs, KJ
The 'minor-dia' is probably what's tight
Retapping won't open the major any larger nor would it have to.
Run a 5/16" drill to depth in the J/B and it should fit.
The same tap is used for both pins, V-minor and Flat-minor.
What changes is the tap/drill used.
HTHs, KJ
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Too many bastardized screws already.
I asked Tom to quit making .308 minor 3/8 11. I fell for the same trap.
I'm on .312 minor 3/8 11 now. I wish everyone would stop using the .308 minor ( there's a .306 one too ) flat bottom screws.
Hi,
My pin is truncated with a slight conical taper and I use a stepped minor to accommodate a tight fitting pin / insert interface. The standard 3/8 14 tap with a .312 minor is somewhat of a loose fit for a pool joint so I create an undersized minor then I hand fit every female shaft thread so when it faces it is very tight. Before this hand fitting procedure two hands can not make the joint facing for the last 1/4" of travel because of the pin's geometry.
It is extra work but I believe it is worth it because stitch ring line ups remain constant over time and repeated use because the insert material does not get a chance to degrade like wood and the very tight fit in the last half turn facilitates that.
So I guess I have the ultimate bastard set up but I like the outcome achieved with my custom made pins and insert. After all cue making is about holding tight repeatable tolerances.
Customers don't like pins that loosen up or degrade the female threads. This was my way to avoid that and it took me 5 years to hone my method.
So I think a bastard thread is good if it has an engineering advantage.
JMO,
Rick
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Agreed. The .308 minor makes no sense to me. That leaves .004" slop on a 5/16" hole. I don't like the .380" barrels, either. He makes mine .375". I drill with a 3/8" bit then ream with a .376" reamer, and the pin fits within .001" every time. Easy. No boring or measuring or tinkering with the pin as the epoxy cures. When I plan out a method for doing something, I do it within the simplest and most idiot proof way I can.
I might take this opportunity to thank Tom. That dude is awesome. Huge asset to the custom cue world.
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You bastardized the hole, not the thread or screw.
Undersized hole is pretty common. Not a good idea on wood if the cue goes to Asia or midwest/southeast .
If you use phenolic insert. there is no need to undersize that hole more than .001".
Joey,
I understand your thoughts but my pin geometry is slightly conical with truncated threads. Because of the slight taper that exists on the pin, a stepped minor allows for my method to work and to hand tune the Garolite insert threads.
Rick
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Rick, would you care to define "truncated" and explain how it applies to the above post?
Eric,
It is easy to google, here is one definition:
(truncated cone) is a solid similar to a cylinder, except that the circular end planes are not of equal sizes.
Furthermore, both end planes’ center points are positioned directly above each other.
My application is explained in my first post above.
Rick
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Eric,
Thanks for pointing out my incorrect usage of the term. Daah! :smilewinkgrin: :scratchhead:
I should have referred to the pin geometry as having a slight conical taper over the 1.250 length business end with the apex of the threads that are truncated. Oops.
Ray Schuler's pin was slightly conical and we took his concept and applied it to a big pin flat face set up. Ray always referred to it as a truncated pin and I got in that habit as a description.
My mentor Ray Hernandez was a tool and die engineer for forty years and he designed our pin before he retired from making cues. He also referred to the pin as truncated.
I will edit my prior posts to make it clear as not to confuse.
Rick
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Tapered minor ?
Joey,
Slightly Tapered pin into stepped minor hole. Larger hole is tweaked on each shaft to obtain very tight fit just before facing.
The taper is only .312 to .3175 and can't be seen with the naked eye but without the tweaking of the stepped minor, the shaft will only screw on half way and reaches refusal.
You can use this method on a non tapered pin as well with a little experimentation. I modify many Omega DPK shafts for customers. Just create a smaller minor where the pin fits very very tightly and will not insert more than half way in because of friction of the pin - insert interface. Then get and use a larger chucking reamer. At about 1000 RPM step the minor just a little. What size reamer? I don't know you have to guess at first then you will most likely need to get another one or may be two. Try fitting the shaft to the cue and see how it goes. You want to have the last turn get very tight as facing happens.
McMaster Carr sells chucking reamers in any size in .0005 increments for about 20.00.
It took me buying three reamers and some trial and error to get my geometry perfect on my set up but now I know how far to insert the reamer, what size for my undersized initial minor and what size final reamer to use. I always go short of that insertion point and test the fit, then sneak up on the final insertion. It is amazing how just .001 makes such a difference concerning " go or no go" in the ID when searching for the perfect reamer size. I eventually interpolated mine down to the .0005 increment. But that just me.
I do a lot of work on Omega DPK cues and have put new inserts in many shafts and made them fit tighter using this method. Makes a big difference. Players don't like loose fitting joints and the stitch rings line up and stay lined up because it is very tight at facing and you can't over tighten to degrade the threads.
If you want your stitch rings to stay lined up over time, this is the way to do it and was the motivation behind this procedure from the get go. I use a 7 step tool change procedure for machining my shafts to that end.
JMO,.
Rick
Slightly Tapered pin into stepped minor hole. Larger hole is tweaked on each shaft to obtain very tight fit just before facing.
The taper is only .312 to .3175 and can't be seen with the naked eye but without the tweaking of the stepped minor, the shaft will only screw on half way and reaches refusal.
You can use this method on a non tapered pin as well with a little experimentation. I modify many Omega DPK shafts for customers. Just create a smaller minor where the pin fits very very tightly and will not insert more than half way in because of friction of the pin - insert interface. Then get and use a larger chucking reamer. At about 1000 RPM step the minor just a little. What size reamer? I don't know you have to guess at first then you will most likely need to get another one or may be two. Try fitting the shaft to the cue and see how it goes. You want to have the last turn get very tight as facing happens.
McMaster Carr sells chucking reamers in any size in .0005 increments for about 20.00.
It took me buying three reamers and some trial and error to get my geometry perfect on my set up but now I know how far to insert the reamer, what size for my undersized initial minor and what size final reamer to use. I always go short of that insertion point and test the fit, then sneak up on the final insertion. It is amazing how just .001 makes such a difference concerning " go or no go" in the ID when searching for the perfect reamer size. I eventually interpolated mine down to the .0005 increment. But that just me.
I do a lot of work on Omega DPK cues and have put new inserts in many shafts and made them fit tighter using this method. Makes a big difference. Players don't like loose fitting joints and the stitch rings line up and stay lined up because it is very tight at facing and you can't over tighten to degrade the threads.
If you want your stitch rings to stay lined up over time, this is the way to do it and was the motivation behind this procedure from the get go. I use a 7 step tool change procedure for machining my shafts to that end.
JMO,.
Rick
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^
I don't know why that would be any better than undercutting the hole of a phenolic insert.
I don't use a reamer at all. I bore the hole shy of .312 with a 1/4 end mill.
When the hole is to size, I replace the 1/4 end mill with a 1/4 head thread mill.
I don't know why that would be any better than undercutting the hole of a phenolic insert.
I don't use a reamer at all. I bore the hole shy of .312 with a 1/4 end mill.
When the hole is to size, I replace the 1/4 end mill with a 1/4 head thread mill.