joint pin question

[scdiveteam]

^
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.

Joey,

Not any better! Just a more controlled method of making the the last turn of the make up be as tight as it can be when facing occurs.

This tightness at facing makes it impossible to over tighten and deform the treads with two hands. If two people with four hands tried to make it tighter I am sure they could budge it a hair but that would be cue abuse. LOL

Ray Schuler's unique piloted metal joint had a tendency to get tighter as you played with it. Many times after playing all night with a Schuler you needed a few extra hands to unscrew them. But that is a different story as he never had Stich rings to line up. His joint is awesome and a great accomplishment that he developed and revised that design 3 times until he got it perfect.

JMO,

Rick

 

[JoeyInCali]

Joey,

Not any better! Just a more controlled method of making the the last turn of the make up be as tight as it can be when facing occurs.

This tightness at facing makes it impossible to over tighten and deform the treads with two hands. If two people with four hands tried to make it tighter I am sure they could budge it a hair but that would be cue abuse. LOL

Ray Schuler's unique piloted metal joint had a tendency to get tighter as you played with it. Many times after playing all night with a Schuler you needed a few extra hands to unscrew them. But that is a different story as he never had Stich rings to line up. His joint is awesome and a great accomplishment that he developed and revised that design 3 times until he got it perfect.

JMO,

Rick

I thought Schuler's got tighter b/c the piloted insert's OD tightened up on the butt's pilot hole . 5/16 14 is lose fit in general. If that insert hit bottom a skosh before faces meet, it'd be tight like a compression fit.

 

[qbilder]

Rick, something is wrong. If this method you describe really is the way you do things, then something is very wrong somewhere. Your tail stock receives a tapered pin. When it seats, can you move it side to side? Nope. Can you push it in farther or pull it out? Nope. Once it seats, it's seated. That tapered fit is itself the lock. If your pin fits this way as you describe, then you would have to have your faces perfect square and your pin & bore be exactly center. We all know that is impossible. You can get close, but it's never perfect. So one of two things is happening. Either your pin isn't seating as you think it is, or your joint faces aren't touching. Can't have both. And if you force it to have both, then you are tweaking your pin, putting significant stress in that joint.

I'm not saying you don't do the things you say you do, just that the method you describe is a machining oxymoron. Seems nice at first thought, but is not only impractical, it's impossible. Is there maybe something you're leaving out? If this method was viable, then it's the way your lathe tail & head stocks would have been designed. The reason they have tapered pin fits is for true center location, and the reason there are no threads or faces is because it would interfere with the tapered pin fit. It wouldn't lock. Does that make sense? It's a big machining no-no.

 

[scdiveteam]

Rick, something is wrong. If this method you describe really is the way you do things, then something is very wrong somewhere. Your tail stock receives a tapered pin. When it seats, can you move it side to side? Nope. Can you push it in farther or pull it out? Nope. Once it seats, it's seated. That tapered fit is itself the lock. If your pin fits this way as you describe, then you would have to have your faces perfect square and your pin & bore be exactly center. We all know that is impossible. You can get close, but it's never perfect. So one of two things is happening. Either your pin isn't seating as you think it is, or your joint faces aren't touching. Can't have both. And if you force it to have both, then you are tweaking your pin, putting significant stress in that joint.

I'm not saying you don't do the things you say you do, just that the method you describe is a machining oxymoron. Seems nice at first thought, but is not only impractical, it's impossible. Is there maybe something you're leaving out? If this method was viable, then it's the way your lathe tail & head stocks would have been designed. The reason they have tapered pin fits is for true center location, and the reason there are no threads or faces is because it would interfere with the tapered pin fit. It wouldn't lock. Does that make sense? It's a big machining no-no.

Eric,

I use my pin as a tool also for another function, not just joining the cue.

The back of my pin is threaded 3/8 16 non tapered and the barrel is also straight. I also ream my hole in the cue larger and the barrel interface is at .3775. The barrel is .372 So there is no lock up. I adjust my concentricity while the 6500 psi epoxy cures with a setting device holding the pin at .0002 to zero as my current tolerance. There are those who don't agree with my methods but I submit that this is my way of getting my very low TRO.

Also I have 40 pins cut down in my shop and create a 60 center on the cut off .372 barrel which sticks out .570 exactly on every shaft to be tapered. This is critical to keep the size differential between my joint and ferrule taper geometry uniform on every shaft. These concentricity devices are inserted in to my shafts at .910 on the joint size and I run on them between centers. I don't thread my shaft after tapering them to final dia. and don't run on a wood center at the joint side for precise control.

So when I taper cut on the x the concentricity becomes perfect to the threads via the concentricity pin device. There is an extra step involved so devices are very tight in the cue so there is no drift involved. I don't use a collets on my six jaw or back chuck during drill and tapping and when the saw cuts both sides the x is true to the threads. No transfer error or chanting of the threads.

All my pins have a run out of .0002 or less every time and i do indicate zero a lot after the epoxy cures and zero run out or very close on the pin works every time because the cue is trued up first before pin install. My tail stock is not involved during my glue up.

Impossible is not in my vocabulary and I always reach for the highest apple on the tree or haven't you noticed.

I just bought a Hardinge lathe with a collet chuck to be the proprietary machine to do my pins and shaft work. I have had precision 5c collets tapered to match my end tapers of my forearm and shaft at finished size. This will eliminate my need to shim my tapered collet on my current late with zig zag paper.

I will have It up and running and let you know how striving for perfect is working out for me. Not going to get there every time but I am going to improve a tad more.

BTW, I am not telling anyone to do as I do and never will do that. Each of us has our way to approach each operation. I just am putting out some food for thought for those patient enough to read a long winded thread. The devil they say is always in the details.

JMOs,

Rick

 

[qbilder]

Goodness, Rick, you're making it difficult to discuss this stuff. Ok, I never insinuated that you use the tail stock to install your pin. I wasn't even referring to pin installation. I was using a general tail stock as an example of tapered pin lock. The morse taper of your tail stock aligns the tool to center, and locks it in place, without screws or faces. That's how a tapered pin works, and seems to be how you describe your joint as working.

If I read correctly, your tapered pin locks in place at the same time your joint faces lock together. If that interpretation is correct, then it's an oxymoron, impossible. You cannot have an effective tapered pin lock in unison with a faced/thread lock. You can have one or the other, not both. You are claiming both, as far as I can tell. Doesn't matter if "impossible" is in your vocabulary or not, it's impossible. But don't take my word for it. Ask any machinist on the planet. And if I am misinterpreting your claims somehow then I apologize.

What ever happened to drilling a hole & tapping it?

 

[RBC]

Eric,

I use my pin as a tool also for another function, not just joining the cue.

The back of my pin is threaded 3/8 16 non tapered and the barrel is also straight. I also ream my hole in the cue larger and the barrel interface is at .3775. The barrel is .372 So there is no lock up. I adjust my concentricity while the 6500 psi epoxy cures with a setting device holding the pin at .0002 to zero as my current tolerance. There are those who don't agree with my methods but I submit that this is my way of getting my very low TRO.

Also I have 40 pins cut down in my shop and create a 60 center on the cut off .372 barrel which sticks out .570 exactly on every shaft to be tapered. This is critical to keep the size differential between my joint and ferrule taper geometry uniform on every shaft. These concentricity devices are inserted in to my shafts at .910 on the joint size and I run on them between centers. I don't thread my shaft after tapering them to final dia. and don't run on a wood center at the joint side for precise control.

So when I taper cut on the x the concentricity becomes perfect to the threads via the concentricity pin device. There is an extra step involved so devices are very tight in the cue so there is no drift involved. I don't use a collets on my six jaw or back chuck during drill and tapping and when the saw cuts both sides the x is true to the threads. No transfer error or chanting of the threads.

All my pins have a run out of .0002 or less every time and i do indicate zero a lot after the epoxy cures and zero run out or very close on the pin works every time because the cue is trued up first before pin install. My tail stock is not involved during my glue up.

Impossible is not in my vocabulary and I always reach for the highest apple on the tree or haven't you noticed.

I just bought a Hardinge lathe with a collet chuck to be the proprietary machine to do my pins and shaft work. I have had precision 5c collets tapered to match my end tapers of my forearm and shaft at finished size. This will eliminate my need to shim my tapered collet on my current late with zig zag paper.

I will have It up and running and let you know how striving for perfect is working out for me. Not going to get there every time but I am going to improve a tad more.

BTW, I am not telling anyone to do as I do and never will do that. Each of us has our way to approach each operation. I just am putting out some food for thought for those patient enough to read a long winded thread. The devil they say is always in the details.

JMOs,

Rick

Rick

Based on your description of how you do your shaft joint work and tapering, I have a question.

Do your measure and ensure that each and every shaft has less then the same .0002" runout all the way down the shaft before and after each tapering?

The reason I ask is because, if your shaft moves any at all and you support it from the center on your pin as you describe, then the pin bore is no longer concentric to the outside of your cue shaft.


Royce

 

[JE54]

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

I've had Rick do quite a few of my shafts with the insert and then tap it.
I can tell you that the last few turns really makes the connection very snug with no movement or play.
It's tight but not too tight.
His work is top shelf and his prices are very fair.
I would suggest anybody with a pin that's 3/8 x 14 and the joint is a little sloppy, give Rick a call to make it as good as new if not better. imo

 

[qbilder]

Rick

Based on your description of how you do your shaft joint work and tapering, I have a question.

Do your measure and ensure that each and every shaft has less then the same .0002" runout all the way down the shaft before and after each tapering?

The reason I ask is because, if your shaft moves any at all and you support it from the center on your pin as you describe, then the pin bore is no longer concentric to the outside of your cue shaft.


Royce

Oh dear, Royce has run out of rubber bands

 

[scdiveteam]

Rick

Based on your description of how you do your shaft joint work and tapering, I have a question.

Do your measure and ensure that each and every shaft has less then the same .0002" runout all the way down the shaft before and after each tapering?

The reason I ask is because, if your shaft moves any at all and you support it from the center on your pin as you describe, then the pin bore is no longer concentric to the outside of your cue shaft.


Royce

Royce,

I don't measure the entire length each time and I never would assume to get .0002 down the length of a wooden shaft. My pin concentricity is between .0002 and zero indicated.

The 60 degree center is put on the concentric pin driver after I adjust and indicate it to zero in the chuck.

I hold the shaft at about .910 in the buck chuck and rear chuck and put a precision face on the joint and then drill and tap to a very tight fit where I must use a chuck in my hand holding the device and holding the shaft in the other hand to crank it out. This is done after finishing and before final tweaking of the stepped minor. The threads have already been stepped drilled a little but not to a final cue fit. To remove the device I hold a small chuck in my hand so I can get more purchase than just holding a cue dia. This allows me to unscrew the device after the shaft is sprayed, wet sanded and buffed.

The precision face that was put on at About .910 never gets faced again because the device guarantees the 90 degree face angle to the centerline of the threads and x axis of the of the shaft.

The shaft taper is cut on this x axis on the very tight threaded insert pin interface. The tapered contour of the shaft is concentric to the device and the threaded shaft insert from .900 to .850. I never test roll my shafts as the device does not come out until after finishing. The roll is always true on the table and there is never an elevation change at the joint when rolled on the rail.

I have been using this method since 2004 and over the years have refined the process. In 2010 I shared this method with the forum and since that time have made a few changes. The post below speaks of facing after the fact and fixed tail stock spring loading. I now have and adjustable tail stock with the spring loading also and can dial in the exact and smallest pressure between centers everytime. Along with my gravity feed follow rest I am creating shafts at a level of quality that I could never have imagined in 2010.

Here is a thread detailing my method that has been improved since 2010 but will outline the procedure as such:

http://forums.azbilliards.com/showthread.php?t=199595


Rick

 

[scdiveteam]

Rick, something is wrong. If this method you describe really is the way you do things, then something is very wrong somewhere. Your tail stock receives a tapered pin. When it seats, can you move it side to side? Nope. Can you push it in farther or pull it out? Nope. Once it seats, it's seated. That tapered fit is itself the lock. If your pin fits this way as you describe, then you would have to have your faces perfect square and your pin & bore be exactly center. We all know that is impossible. You can get close, but it's never perfect. So one of two things is happening. Either your pin isn't seating as you think it is, or your joint faces aren't touching. Can't have both. And if you force it to have both, then you are tweaking your pin, putting significant stress in that joint.

I'm not saying you don't do the things you say you do, just that the method you describe is a machining oxymoron. Seems nice at first thought, but is not only impractical, it's impossible. Is there maybe something you're leaving out? If this method was viable, then it's the way your lathe tail & head stocks would have been designed. The reason they have tapered pin fits is for true center location, and the reason there are no threads or faces is because it would interfere with the tapered pin fit. It wouldn't lock. Does that make sense? It's a big machining no-no.

Eric,

Forgive me but I don't understand what it is your talking about above for real. Not trying to be an ass just confused why you can't grasp the notion of a stepped minor within the shaft insert and how that would interface with a slightly tapered pin. .0055 over a 1.250' length of the business end going into the shaft. I reiterate the the embedment side in the butt is a straight 3/8 16 tip with a straight .372 barrel.

Anyway that is the way I do it and next time your in Chicago i hope you can stop by to see it for yourself as you would be a welcomed guest.

I am always searching for even the very lowest of percentile improvements in all phases of my cue making procedures and am currently revising all my written procedures and prints for future submission for an ISO 9001 Review. So there is no "if" in the way I do things.

After all cue making is all about holding the tightest tolerances possible for repeatability. In my minds eye there is always room for improvement if there is a will to do so.

I personally don't mind adding steps when it is proven to increase quality and repeatability but conversely I love to remove steps in a procedural revision for the same reason.

The way I approach any disapline is that if you are not moving forward you will surely be falling behind.

JMO,

Rick

 

[scdiveteam]

I've had Rick do quite a few of my shafts with the insert and then tap it.
I can tell you that the last few turns really makes the connection very snug with no movement or play.
It's tight but not too tight.
His work is top shelf and his prices are very fair.
I would suggest anybody with a pin that's 3/8 x 14 and the joint is a little sloppy, give Rick a call to make it as good as new if not better. imo

Thanks for the kind words Chief.

Rick

 

[qbilder]

Eric,

Not trying to be an ass just confused why you can't grasp the notion of a stepped minor and how that would interface with a slightly tapered pin. .0055 in 1.250' length of the business end going into the shaft.

I don't even know where to begin. This is so bizarre. I'm trying to help you understand a very basic mechanical concept, and rather than consider the validity of what I'm telling you, you'd rather belittle my intelligence in attempt to stay relevant. Carry on with your impossible feats of machining, and good luck with your ISO review. Maybe they can explain it to you better than I. Missing the forest through the trees :shakehead:

 

[JoeyInCali]

I don't even know where to begin. This is so bizarre. I'm trying to help you understand a very basic mechanical concept, and rather than consider the validity of what I'm telling you, you'd rather belittle my intelligence in attempt to stay relevant. Carry on with your impossible feats of machining, and good luck with your ISO review. Maybe they can explain it to you better than I. Missing the forest through the trees :shakehead:

I like the two registers to be 90 degrees of each other. Even in compression ( slightly undersized hole ).
Being 90*, they wouldn't be fighting each other.
THAT's WHAT the flat bottom screws were made for .

 

[qbilder]

I like the two registers to be 90 degrees of each other. Even in compression ( slightly undersized hole ).
Being 90*, they wouldn't be fighting each other.
THAT's WHAT the flat bottom screws were made for .

Bingo! That's too simple, though.

 

[scdiveteam]

Post deleted..........

 

[JoeyInCali]

deleted

,

Rick

I didn't even read what you are referencing to.
TAPERED hole and FACE, will not be 90 degrees of each other .
You like it that way. If that's your "proprietary" way, it's fine.
I don't think Bender designed that screw to be that way though.

The FLAT bottom pins bottoms are perfectly 90* of the shafts' and butts' face when done right. That's what they are designed for .
Why in the world would anyone want a tapered hole is what me and Eric can't figure out. If you want a tighter fit, all you need to do is bore that hole a little undersized . 001" for phen insert is plenty as it's a very hard material.

It's not a poke in a hole. It's working smart with a screw we are lucky to have .

 

[scdiveteam]

I didn't even read what you are referencing to.
TAPERED hole and FACE, will not be 90 degrees of each other .
You like it that way. If that's your "proprietary" way, it's fine.
I don't think Bender designed that screw to be that way though.

The FLAT bottom pins bottoms are perfectly 90* of the shafts' and butts' face when done right. That's what they are designed for .
Why in the world would anyone want a tapered hole is what me and Eric can't figure out. If you want a tighter fit, all you need to do is bore that hole a little undersized . 001" for phen insert is plenty as it's a very hard material.

It's not a poke in a hole. It's working smart with a screw we are lucky to have .

I get what your are saying and understand.

Again, There is no taper in the shaft insert hole it is a stepped minor. The pin embedment side in the butt is straight 3/8 16 tpi with a straight barrel. This is not Bender' Pin. It is a 3/8 14 custom designed by a tool and die engineer with 40 years experience.

If you were in my shop Joe and saw my special tooling and watched the total procedure from taping the insert, total tapering. and the final tweaking of the insert when making up the cue to the shaft including ring line up, you would have a different view of the matter I am sure. It is are part of a total system of the shaft building.

There are other things here regarding a ground drap to undersize the initial minor and details regarding the final stepping of the joint side of the minor.

Rick

 

[qbilder]

Rick, you really need to make a mock-up of your joint system and split it down the middle with a band saw. This will reveal the awkward fit Joey & I are trying to explain to you. The system as you describe it is two dissimilar shapes that you expect to join accurately with a high degree of contact. We learn as toddlers that dissimilar shapes don't fit correctly. The stepped hole doesn't matter. Rather than a straight bored hole, it's a series of straight bored holes. At the most, you can expect the crest edge of each step to contact the pin's minor, but I doubt that's the case in reality. Seriously, try the experiment.

 

[JoeyInCali]

I get what your are saying and understand.

Again, There is no taper in the shaft insert hole it is a stepped minor. The pin embedment side in the butt is straight 3/8 16 tpi with a straight barrel. This is not Bender' Pin. It is a 3/8 14 custom designed by a tool and die engineer with 40 years experience.

If you were in my shop Joe and saw my special tooling and watched the total procedure from taping the insert, total tapering. and the final tweaking of the insert when making up the cue to the shaft including ring line up, you would have a different view of the matter I am sure. It is are part of a total system of the shaft building.

There are other things here regarding a ground drap to undersize the initial minor and details regarding the final stepping of the joint side of the minor.

Rick

Well, that's different . I thought you said you used a tapered reamer .
Stepped minor is not a secret .

 

[RBC]

Royce,

I don't measure the entire length each time and I never would assume to get .0002 down the length of a wooden shaft. My pin concentricity is between .0002 and zero indicated.

The 60 degree center is put on the concentric pin driver after I adjust and indicate it to zero in the chuck.

I hold the shaft at about .910 in the buck chuck and rear chuck and put a precision face on the joint and then drill and tap to a very tight fit where I must use a chuck in my hand holding the device and holding the shaft in the other hand to crank it out. This is done after finishing and before final tweaking of the stepped minor. The threads have already been stepped drilled a little but not to a final cue fit. To remove the device I hold a small chuck in my hand so I can get more purchase than just holding a cue dia. This allows me to unscrew the device after the shaft is sprayed, wet sanded and buffed.

The precision face that was put on at About .910 never gets faced again because the device guarantees the 90 degree face angle to the centerline of the threads and x axis of the of the shaft.

The shaft taper is cut on this x axis on the very tight threaded insert pin interface. The tapered contour of the shaft is concentric to the device and the threaded shaft insert from .900 to .850. I never test roll my shafts as the device does not come out until after finishing. The roll is always true on the table and there is never an elevation change at the joint when rolled on the rail.

I have been using this method since 2004 and over the years have refined the process. In 2010 I shared this method with the forum and since that time have made a few changes. The post below speaks of facing after the fact and fixed tail stock spring loading. I now have and adjustable tail stock with the spring loading also and can dial in the exact and smallest pressure between centers everytime. Along with my gravity feed follow rest I am creating shafts at a level of quality that I could never have imagined in 2010.

Here is a thread detailing my method that has been improved since 2010 but will outline the procedure as such:

http://forums.azbilliards.com/showthread.php?t=199595


Rick

Rick

It's really hard to read through all that and weed out the answer to my question.

Do you taper the shafts any at all after you've installed your special pin to .0002" runout? If the answer is yes, and the shaft moves any at all between the time the insert is installed and any turns there after, the bore for your stepped insert will not be concentric to the outside of the cue shaft. This is assuming the turns are done between centers. If the shaft is mounted on a drive pin in a chuck for any tapers after the installation of your special pin to .0002" runout, then the shaft must remain perfectly straight. If it moves in this scenario, then the tip would not align with the live center at the opposite end from your drive pin. Of course, you could still turn the shaft straight from this, given enough material is left, but then the shaft would just move off once the tail stock is removed and you'd have the same result.

I believe you probably make straight shafts, I'm just not sure anyone is understanding how you go about it. I'm trying, but so far 2 plus 2 is coming out to -13.

Royce