how to design a true parabolic/conical tapered cue- ?

JoeyInCali

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hey joey, thanks for the reply. are you referring to the definition of "parabola" itself? or as it might pertain to cuemaking?
I could very well have been wrong by using that term and please let me know if so
the carom and snooker cues I have no straight parts from tip to butt, not bigger than an inch, anyway
Ok, let's just keep it simple, "parabolic taper " on cues have a curve or two .
 

HawaiianEye

AzB Silver Member
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Somehow , Kao Kao , who has a really fancy factory has not copied the taper .
SW's assembly is actually fairly simple .
I don't know if they've copied that .
But, if you are making cues in China, they better be cored .
SW's are not .
So, when you see a SW with ebony nose, it is ebony nose .
Do most American custom cue makers core ebony noses?

If so, would it play pretty much the same as solid ebony if you cored it with a dowel fashioned out of laminated or pie-segmented ebony.
 

JoeyInCali

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Do most American custom cue makers core ebony noses?

If so, would it play pretty much the same as solid ebony if you cored it with a dowel fashioned out of laminated or pie-segmented ebony.
Yes. Almost all.

I don't know who does that . It should be but more stable b/c the center is more protected from the elements .
 

MVPCues

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hey joey, thanks for the reply. are you referring to the definition of "parabola" itself? or as it might pertain to cuemaking?
I could very well have been wrong by using that term and please let me know if so
the carom and snooker cues I have no straight parts from tip to butt, not bigger than an inch, anyway



how come? stick with "conical" if that makes more sense.
do you think there's anything inherently wrong with building/playing with a cone-shaped cue?
do any of y'all?

thanks for the replies-
My response was in jest, and a result of a lot of water under the bridge (a lot of posts in this forum on the subject) when it comes to parabolic tapers. It sort of became a buzz word that IMO was applied to all tapered shafts that had a curve to them. There was even some speculation that a parabolic shaft reflected feedback to the player like how a parabolic satellite dish reflects signals. So in short, you can ignore my post.

There is nothing inherently wrong with any of the different tapering ideas. It all depends on how they are used, what diameters, what materials, and what the customer likes in terms of feel and stiffness. Joey mentioned multiple liner tapers. A shaft with 3 different linear tapers starting at specific points is hard to find fault in. Lots of folks have done that including some big name semi custom production companies. Lots of folks have made long tapers that have very gradual increase and then that nice looking curve sweeping out to the joint. Lots of shafts are close to cones, but they typically have very small tip diameters.
 

Ssonerai

AzB Silver Member
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A parabola is the result of the intersection of a plane and a cone.
So a parabolic curve is is easy to generate.

DSC_0013.JPG
DSC_0015.JPG


If the centers are raised to generate a cone in the work, but the cutter passes over it as a skew angle, the result will be parabolic or hyperbolic
I didn't want to take the time to search my photos: the above are actually using a pattern under the centers to trace a bullnose follower attached to the left planer column. But if the cutter were ball nosed, and skewed over top, it could generate a curve without a pattern. It takes a lot of cut-'n-try to find the best approach & angles, though.

My shafts have curves. & the forearms often do. The joint is somewhat like bamboo - kind of knobby where the forces are greatest.
The joint does not actually bulge, but the curve/taper stops from the forearm until about 1-1/2" past into the shaft. Then the shaft reduces on a curve somewhat rapidly, and finishes out with a barely perceptible few .001's in the last 12" to ferule.

OTOH, I am a part time hobby cue-maker with miniscule output.
:)

smt

PS: MVP was typing faster than me - It would seem to be difficult to fit a true parabolic taper to the whole length of a shaft and get the best distribution of force. Even looking way out on the curve where it is almost straight, it still seems an awkward fit without modifiying the ends. If a person really bought into the notion of "reflected energy" or some such, the better curves to explore would be caternary. But that is way above my math skills. I can lay one out, but i could not begin to analyze why one might work better or not. I think most of us use experience playing, and the gradual accummulation of an instinctive sense of what "feels" right to us. Which is subjective enough that a cue with a hit to fit almost anyone is probably out there, made by someone. :)
 
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evergruven

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My response was in jest, and a result of a lot of water under the bridge (a lot of posts in this forum on the subject) when it comes to parabolic tapers. It sort of became a buzz word that IMO was applied to all tapered shafts that had a curve to them. There was even some speculation that a parabolic shaft reflected feedback to the player like how a parabolic satellite dish reflects signals. So in short, you can ignore my post.

all good, I figured it was some joke I wasn't hip to
honestly, I'd seen some cuemakers discuss the term in old threads and thought it meant "conical"
it appears I should have just stuck with the cone :)
learn something new every day tho-

Lots of shafts are close to cones, but they typically have very small tip diameters.

right, this is one of the main reasons I posted the thread in the first place
I'd like to have a cue built that has an ~11.75 tip, and is shaped like a cone
but I don't want a thick shaft, as I have small hands and use an open bridge
that's why I'm curious about how you cuemakers actually make a cone
 

MVPCues

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I'd like to have a cue built that has an ~11.75 tip, and is shaped like a cone
but I don't want a thick shaft,

I often want the impossible in my life as well. A lot of the LD "conical" shafts with small tips aren't really conical, they are much closer to three linear tapers.

I'm curious about how you cuemakers actually make a cone

With a cutter. No, seriously. If the tip is 11.75 mm and the joint is a typical .845", there is only one way to make a concial shaft between those two points. There is only one straight line between 11.75mm and .845. If such a shaft gets too fat for your hands/feel/bridge length, then you don't really want a conical taper.
 

JoeyInCali

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You guys have DPK's book/journal ?
He has his shaft taper numbers there.
Down to every quarter of an inch from tip to the joint face.
 

evergruven

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I often want the impossible in my life as well. A lot of the LD "conical" shafts with small tips aren't really conical, they are much closer to three linear tapers.

we're tuned in :) I know it's a bit counterintuitive, and that's ok. I'm just looking to learn.
in truth, the 12mm carom cue I have plays and feels fine, but the balance on it is too far back.
as long the cue feels good in general, I think I'll be ok with the cone.

With a cutter. No, seriously. If the tip is 11.75 mm and the joint is a typical .845", there is only one way to make a concial shaft between those two points. There is only one straight line between 11.75mm and .845. If such a shaft gets too fat for your hands/feel/bridge length, then you don't really want a conical taper.

good info., thanks. I can see where the cone might end at the joint- what if the cone ended at the buttcap tho?
could that stretch the dimensions of the cone, so that the shaft would be less fat, even marginally?
and I suppose that would determine the thickness of the joint, which would also be interesting

about the joint- I've heard of cuemakers that value joint thickness as a cue aspect that really affects the hit of a cue. do you agree?
I think the idea might be that a thick/strong joint helps energy remain in the cue, but I'm not sure.
 

DaveK

Still crazy after all these years
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If a person really bought into the notion of "reflected energy" or some such, the better curves to explore would be caternary. But that is way above my math skills.

This is what I think as well, a catenary curve (hyperbolic cosine in math terms) would seem a better choice for structural items. BTW, for those not familiar with catenary curves a great example is the shape of the cables in a suspension bridge. There is no lateral stress, only tension.

I can lay one out, but i could not begin to analyze why one might work better or not. I think most of us use experience playing, and the gradual accummulation of an instinctive sense of what "feels" right to us. Which is subjective enough that a cue with a hit to fit almost anyone is probably out there, made by someone. :)

Aye, subjective indeed !

Dave
 

MVPCues

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we're tuned in :) I know it's a bit counterintuitive, and that's ok. I'm just looking to learn.
in truth, the 12mm carom cue I have plays and feels fine, but the balance on it is too far back.
as long the cue feels good in general, I think I'll be ok with the cone.



good info., thanks. I can see where the cone might end at the joint- what if the cone ended at the buttcap tho?
could that stretch the dimensions of the cone, so that the shaft would be less fat, even marginally?
and I suppose that would determine the thickness of the joint, which would also be interesting

about the joint- I've heard of cuemakers that value joint thickness as a cue aspect that really affects the hit of a cue. do you agree?
I think the idea might be that a thick/strong joint helps energy remain in the cue, but I'm not sure.

A cone from tip to butt would throw off something somewhere. 10.5 mm tip for a typical joint and butt size. For a typical 12.5mm tip, either the joint is going to have to be really thin or the butt is going to have to be really fat.

I've never made and hit with a cue with a really small or really fat joint diameter, but yeah something will change about it, and too small would be weak.
 

evergruven

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A cone from tip to butt would throw off something somewhere.

thanks, interesting- I was thinking from a feedback perspective, it would be nice to have that energy from the tip go all the way down
but I can kind of visualize that, more length, more chance something goes askew- shaft to joint seems easier/smarter? to control.

10.5 mm tip for a typical joint and butt size. For a typical 12.5mm tip, either the joint is going to have to be really thin or the butt is going to have to be really fat.

this is if a conical taper is applied?
 

JoeyInCali

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A cone from tip to butt would throw off something somewhere. 10.5 mm tip for a typical joint and butt size. For a typical 12.5mm tip, either the joint is going to have to be really thin or the butt is going to have to be really fat.

I've never made and hit with a cue with a really small or really fat joint diameter, but yeah something will change about it, and too small would be weak.
That would be a 1-piece house cue with one angle .
It will have a skinny middle for sure .
Fat bottom too .
 

Hits 'em Hard

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This thread is all over the place. Some are talking about butts while others invoke shafts.

There is no such thing as a curve it's all straight lines between points even if the points are very close to each other.

It appears to my mind's eye that in order for a shaft to have a curve in it's taper it will be necessary for it to be fatter somewhere upstream of the joint than the joint is. Silly idea.

Sheldon: Can you take a minute and explain this line of code? Thanks

N6 G02 X30. Y-.1691 I-2.8437 J-1161.3056
Visually, our eyes are flawed. It leads to some very bad assumptions about what is actually in front of your. May I ask, at which level of mathematics are you proficient at?
 

JC

Coos Cues
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Visually, our eyes are flawed. It leads to some very bad assumptions about what is actually in front of your. May I ask, at which level of mathematics are you proficient at?
High school trig.

If it curves it shrinks down stream. It either ends up with an innie or an outie. Not a complex concept.
 

BarenbruggeCues

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For me this subject of shaft tapers gets over thought to the point it can make your eyes bleed reading about some of it.
It is such a simple process to draw out a shaft taper. Simply decide what you would like your final product to be and put it down in the cad process.
Does it really matter if it's a curved line or a bushel basket full of straight little lines?
All I know is when I draw mine the cad program calls it an arc. No matter how large I blow it up I don't see any straight lines in the drawing except for any areas I draw between 2 points. If I draw between 3 points, it looks like a curve to me in the drawing and just as important in the finished product once completed. And after it's sanded and sealed and completed I can't feel any little lines in my hand.
In the end isn't that what we're attempting to do?
It's already been explained what the OP was asking isn't possible without creating a frankenstein cue. Maybe that's what he's attempting after all.

Just food for thought tho...one time I rebuilt a very old 2pc cue that needed some serious work at the joint and a new shaft. Joint was around .760 and I said to myself this cue will play like crap when I'm done because of a predetermined thought I had about joint size and what it should be to make a cue play good. Completed the cue played just fine and potted balls as well as any cue built...just not as good as one of mine. 😎
 

Hits 'em Hard

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High school trig.

If it curves it shrinks down stream. It either ends up with an innie or an outie. Not a complex concept.

It seems to be a lot more complex than you give it credit for. I wish I could find the formulas to give you the correct frame of mind. A curve doesn’t have to be static. It can have multiple bend points. And the key word is point. In calculus you would have learned that no matter what, a curve will never have more than a single consecutive point of contact to a straight line. So no matter what parabolic curve/taper we are talking about, there should never be a straight section.
 

JC

Coos Cues
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It seems to be a lot more complex than you give it credit for. I wish I could find the formulas to give you the correct frame of mind. A curve doesn’t have to be static. It can have multiple bend points. And the key word is point. In calculus you would have learned that no matter what, a curve will never have more than a single consecutive point of contact to a straight line. So no matter what parabolic curve/taper we are talking about, there should never be a straight section.
None of that matters. If you add a curve to a cue shaft or butt it will have to get smaller in ID than it was previously upstream. This is fine if the smaller section falls at the end of the butt but anywhere else and you have yourself a funky odd looking POS with a lump in it.

Nothing complex about that. It's 2D conception, not the frigging universe big bang. You may fancy yourself a mathematician but this is not calculus.
 
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