Dime vs. Nickel radius tip

[Scott Lee]

ajhnnyz86...The contact area between the tip and ball is the same size, regardless of tip size, or shape...about 1/8", or 3mm. Shape of the tip doesn't matter. There's no such thing as a "too round" tip...round hits round.

Scott Lee
www.poolknowledge.com

dime because someone said it results in less deflection. perhaps, the less contact area means less friction so it bends towards the ball less which is one part of deflection. it only does this for an extremely short amount of time before it bends away from the ball.

its contact point is closer to where i point.

also i only have a dime shaper

 

[Patrick Johnson]

Originally Posted by cad1illac
Fact both Paul Heubler and Bob Meucci have proven that a dime is more accurate because you are hitting more accurately the spot on the cue ball you are aiming at.

Sorry, but I have my doubts. Suppose you wanted to produce a spin/speed ratio of 0.7, for instance. You wouldn't be thinking "0.7", but you know what you want the cueball to do and it happens that 0.7 would give it to you. Would you want a tip curvature such that displacing the shaft 1mm would change the ratio by, say, 0.1? Or would you want it to change by 0.05? I think the second one would be the right choice. It's the same idea as the principle behind the micrometer: transform relatively large movements into small distances.

At least that's the way I see it. I could be wrong... just discussing.

Jim

I don't think Huebler and Meucci "proved" anything like cad1illac says, and I agree with Jim that the "micrometer effect" is real - but I don't think it makes a practical difference.

I don't think the "micrometer effect" makes a practical difference because the total increase in the amount of shaft movement to cover the entire range of tip offsets (from centerball to 1/2 radius out) is miniscule - probably a couple of millimeters of total increased shaft movement for a nickel shape vs. a dime shape, which I don't think is enough to have a real practical effect on tip placement accuracy.

However, I think a dime shape can produce a practical improvement in tip placement accuracy, but for an entirely different reason - because it makes it possible to use a smaller tip which makes it easier to see exactly where the tip is contacting the CB. To see what I mean, imagine using a ridiculously large tip (say the blunt end of a baseball bat) vs. a ridiculously small tip (say a needle point) - the smaller the tip the easier it is to see exactly where it's contacting the CB.

This is why I use a 10mm tip. It isn't a huge difference like my baseball bat vs. needle point comparison, and some of the effect may be me simply being more aware of tip placement accuracy, but it's a tangible and practical benefit.

pj
chgo

 

[PetToilet]

ajhnnyz86...The contact area between the tip and ball is the same size, regardless of tip size, or shape...about 1/8", or 3mm. Shape of the tip doesn't matter. There's no such thing as a "too round" tip...round hits round.

Scott Lee
www.poolknowledge.com

what i meant is it is the contact point is more centered to the stick due to the radius, affecting the force vectors and deflection characteristics

 

[whitewolf]

ajhnnyz86...The contact area between the tip and ball is the same size, regardless of tip size, or shape...about 1/8", or 3mm. Shape of the tip doesn't matter. There's no such thing as a "too round" tip...round hits round.

Scott Lee
www.poolknowledge.com

I have a friend who has a 14mm shaft. Everyone who tries it out claims that this cue is much more accurate, including me. More rubber hits the road with this tip. Size does matter - hugely.

Scott, the shape of the tip also makes a huge difference.

You are giving one of your 'it's the magician and not the wand' arguments.

 

[Patrick Johnson]

johnnyz86:
what i meant is it is the contact point [with a dime shaped tip] is more centered to the stick due to the radius, affecting the force vectors and deflection characteristics

1. With a rounder tip the contact point is closer to the tip's edge, not its center.

2. That wouldn't matter to squirt ("deflection") anyway, because the only significant force contributing to squirt is the inertia of the mass near the tip being pushed aside by the rotating CB.

Some do claim that a more round tip produces slightly less squirt (presumably for other reasons), but the amount claimed isn't enough to matter.

pj
chgo

 

[Patrick Johnson]

...The contact area between the tip and ball is the same size, regardless of tip size, or shape...about 1/8", or 3mm. Shape of the tip doesn't matter. There's no such thing as a "too round" tip...round hits round.

Scott Lee
www.poolknowledge.com

I have a friend who has a 14mm shaft. Everyone who tries it out claims that this cue is much more accurate, including me. More rubber hits the road with this tip. Size does matter - hugely.

Scott, the shape of the tip also makes a huge difference.

Sorry, Scott's right. The things you claim as fact are (wrong) impressions with no basis in reason.

pj
chgo

 

[JimS]

Accurate? What does "accurate" mean?

Scott is absolutely accureate when he says that only a very small patch of the tip touches the cb. I believe Patrick is accuraste in his assessment that using a very small diameter shaft makes it easier to see exactly where that very small patch is hitting the cb.

So what does "accurate" refer to?

 

[Patrick Johnson]

Jal:
...during the few times I've played with a nearly flat tip, I couldn't attempt much spin without a miscue. Have you found that if you're particularly careful about chalking, which I wasn't, it's not a problem?

I got a chance to really test this today - one of my hard Moori tips delaminated, leaving a perfectly flat surface with sharp edges. So before relacing it I chalked it up and tried to spin the cue ball. No problem. It was very easy to put maximum spin on the CB (hitting a full 1/2 radius from center) without miscueing, even hitting the CB very hard. Apparently with a well chalked tip it doesn't take much surface contact to get the friction necessary to spin the ball as much as you want.

pj
chgo

 

[Tbeaux]

I use a nickle. I'll probably play with it till it mushrooms to a quarter then make a withdrawl of the intrest so I can maybe one day, buy a new tip.:grin-square:

Terry

 

[JoeW]

After reading much, not all, of this thread it made me think and attempt to justify why I use a dime radius. I do not doubt the size of the contact area as related by several of the pros. However, I find that I continue to return to my 11.75mm dime radius tip. I probably try using my other cues once a month or so and no matter how many times I check, I always find that my snooker cue (10mm) and the Predator are my preferred sticks. Friends who are excellent players have told me many times that I should change back to 14mm and a nickel radius. I respect their opinion and yet find that I simply play better with a small diameter shaft and a dime radius.

WHY

First I have small hands and like the feel of the smaller shaft, but I can use a larger one. The tip size is important to me because it feels like I have better control of the exact place on the cue ball. This may or may not be true, but it feels that way. Larger tips and shafts seem to have to much surface area that needs to be aligned for the particular hit. Follow and draw are both more accurate with my smaller tools. Probably the easiest comparison I can make is that large tips are like the fat end of a Sharpie while my smaller tips are like the narrow end of the Sharpie. Both ends work but the smaller end allows me to be more accurate.

I think that it is true that my smaller tips are less forgiving and therefore take longer to master. Once mastered, I get more accurate results. It is probably all in my head (not the tip) but that is my rationalization.

Rationalize: sounds good won’t fly – I know, I know.

 

[Jal]

I got a chance to really test this today - one of my hard Moori tips delaminated, leaving a perfectly flat surface with sharp edges. So before relacing it I chalked it up and tried to spin the cue ball. No problem. It was very easy to put maximum spin on the CB (hitting a full 1/2 radius from center) without miscueing, even hitting the CB very hard. Apparently with a well chalked tip it doesn't take much surface contact to get the friction necessary to spin the ball as much as you want.

pj
chgo

Appreciate the feedback, Patrick.

I am surprised and scratching my head? I would have thought that while the force of friction should be about the same if no miscue occurs, the tip-chalk interface would be much more prone to failing in shear (miscuing), since all of the force is now being generated over a small area. In other words, the shear 'stress' (force divided by area) should be proportionally greater as the contact area is diminished. I thought that this explained my experience with a flat tip.

Is it possible that the contact area isn't reduced that much? Or, since the normal force (perpendicular to the surface) is also acting over the smaller area, perhaps this increases the threshold for failure in shear? Whatever, live and learn. Thanks for apparently debunking a myth which I was trying to propagate.

What then exactly happens during a miscue when exceeding the miscue limit of 1/2R?

Jim

 

[Jal]

After reading much, not all, of this thread it made me think and attempt to justify why I use a dime radius. I do not doubt the size of the contact area as related by several of the pros. However, I find that I continue to return to my 11.75mm dime radius tip. I probably try using my other cues once a month or so and no matter how many times I check, I always find that my snooker cue (10mm) and the Predator are my preferred sticks. Friends who are excellent players have told me many times that I should change back to 14mm and a nickel radius. I respect their opinion and yet find that I simply play better with a small diameter shaft and a dime radius.

WHY

First I have small hands and like the feel of the smaller shaft, but I can use a larger one. The tip size is important to me because it feels like I have better control of the exact place on the cue ball. This may or may not be true, but it feels that way. Larger tips and shafts seem to have to much surface area that needs to be aligned for the particular hit. Follow and draw are both more accurate with my smaller tools. Probably the easiest comparison I can make is that large tips are like the fat end of a Sharpie while my smaller tips are like the narrow end of the Sharpie. Both ends work but the smaller end allows me to be more accurate.

I think that it is true that my smaller tips are less forgiving and therefore take longer to master. Once mastered, I get more accurate results. It is probably all in my head (not the tip) but that is my rationalization.

Rationalize: sounds good won’t fly – I know, I know.

Dr. Joe,

I don't know if you read it, but I argued that a larger radius is potentially more accurate. Let me clarify, if possible.

I think it depends on how you perceive the tip offset. If you judge it by the amount of shaft displacement from centerball, I think a larger radius is better, in that it spreads the bounded range of spins over a wider range of mechanical sideways displacements (micrometer style). It's also more forgiving of stroke errors (e.g. swoop) since it takes a greater deviation to alter the spin by some amount. However, if you perceive and execute the whole operation as an exercise in contacting a particular spot on the cueball, for what it's worth, I agree with you and others that a smaller radius and shaft has the advantage.

Is that a distinction without a difference? In my mind it isn't, but with your background and expertise, I'll of course defer to you.

Jim

 

[CocoboloCowboy]

I vote for a

 

[Scott Lee]

Ray...As Joe Friday said..."Just the facts!" It's not the arrow, it's the indian!:grin: Tip size, shape, construction, or roundness are, for the most part, irrelevant. A good player can execute well with any decent tip. People may PREFER one variable over another, but actual results (in the hands of an expert) will very likely be close to the same. I've owned shafts from 14mm down to 11mm, and they all work just the same.

Scott Lee
www.poolknowledge.com

You are giving one of your 'it's the magician and not the wand' arguments.

 

[JoeW]

Thanks JAL, your thoughts are always useful to me. Maybe I just need to give that larger radius and nickel shape a thorough work out. Say a week or two. I quit playing in the leagues lately and mostly play against the ghost. So I can give it a good work out for a week and see if my shooting improves.

More forgiving is better.

 

[Proper_English]

For 12.7-13+ I like a dime.

Anything around 11-12mm I like it to be more curved than a dime, very round.

BTW, figuring out how to evenly get a tip so round isn't easy...I tried a few different tools and found that if I tilt a Cuetec Bowtie at an angle, and sand the tip on the edge of the tool, a much acuter radius can be achieved...a block and sand paper would probably be easier, but I'd have to make it first.

-Aaron

 

[Patrick Johnson]

No practical difference

Guess it's time for me to post this drawing again...

The two shafts on top are both 12.75 mm (1/2") and the ones on the bottom are both 10.0 mm (3/8"). Nickel shaped tips are on the left; dime shaped tips on the right.



You can see that it's possible with both tip sizes and shapes to hit the cue ball all the way out to the miscue limit (1/2 radius/30 degrees from center). However, a nickel shape makes contact with the CB closer to the edge of the tip for more shots. I don't think this matters, because the edge of the tip compresses on impact and produces plenty of friction.

Jal's point about greater precision and less stroke error with a flatter tip is shown by the fact that the nickel shape uses all of the tip width as it traverses the entire "contact range" on the CB (from centerball to 1/2 radius out) while the dime shape uses a millimeter or so less of its width. I also don't think this matters, because the difference is so small (the average difference over the range of tip offsets appears to be less than 1 mm).

In other words, I don't think there's much, if any, practical playing difference between a nickel and dime shape.

pj
chgo

 

[Patrick Johnson]

Visual comparison

Here's another drawing I have laying around - this one compares nickel and dime shapes visually. On both size tips the dime shape is the highest edge and the nickel shape is the curved black line beneath it. You can see that the difference is very slight, and almost nonexistent for smaller tips.



pj
chgo

 

[Jal]

...In other words, I don't think there's much, if any, practical playing difference between a nickel and dime shape.

Great diagrams.

Just to back up what you're saying with some numbers, the rate of change of actual offset (contact point) with apparent offset (shaft offset) is about 0.766 with a dime radius, and 0.735 for the nickel radius, or about 4% more for the dime. That's not much, although in principle at least, nickel is thus slightly better in that respect. Any stroke error that affects the location of the actual contact point will be slightly less of a problem as far as the simple geometry goes. However, when you factor in a plausible increase in squirt, even that small benefit may not be what it seems.

(The above numbers use 11/32" and 13/32" for the dime and nickel radii, which is close, but not exact.)

Jim