Optimal Cue Tip Diameter
9/4/2012 12:23:54 PM
Optimal Cue Tip Diameter
I favor the dime shape over the nickel. But by the time I think it's time to re-shape - it IS the shape of a nickel already...
Given everyone refers to the radius of dimes and nickels as the quintessential curve, one wonders why the penny - wasn't the obvious choice?
It is, after all, between the dime and nickel - isn't it?
Optimal Cue Tip Diameter
Replies & Comments
Mitch Alsup on 9/4/2012 2:50:08 PM
I know several people who use tips with a smaller radii than a dime I know several people who use a quarter tip radii on their break cues
I have been wondering for a while if the diameter of a tip influences how hard it feels. That is:: does a hard tip on an 11mm ferrule feel as hard as the same tip on a 14mm ferrule? {I think the answer is NO the smaller diameter feels softer, but I won't get to test my theory for a few more months (at tip replacement time).}
Zeke on 9/4/2012 7:45:58 PM
I think it all comes down to p.s.i.'s
Remember the old Ripley's type puzzles? "Which exerts more p.s.i.'s, the weight of the tire on a Buick on the blacktop - or, the weight of the diamond stylus on a record groove?
The answer of course, was the diamond needle because - the pressure - in relationship to the contact surface area it rests upon - on the LP groove was so miniscule, the .005" stylus with 2 grams of weight atop - was far greater than 1,000 pounds on the comparatively huge surface area involved, i.e., say a square foot of macadam...
I think the solution to your puzzle rests in the surface area of contact - logic would presume the pointier the tip, the greater the pressure because the "area" it strikes, is smaller with a pointier tip.
More subjectively, how it "feels" - is a whole 'nother kettle of fish.
I should add:
"The o.d. of the overall cue tip (12mm - 14mm) - has little relevance to the "point" of contact near the tip center - which is the ONLY contact 'zone' involved."
Cue tip diameter is irrelevant. Cue tip radii (and resilience of the tip) is all that matters when calculating "hardness and feel" beyond anecdotal guessing.
Fenwick on 9/5/2012 6:58:37 AM
The theory is over 12 mm nickle shape. Under 12 mm dime shape. I play with a Z2 that's 11.75 - 11.69. I have two. The dime shape works for me. I have Schon Buffalo hide tips. Tips last me at least a year or more. I use the Ulti-Mate Cue Tip Tool to shape and burnish.
Zeke: Consider 2 cues: one with a 10mm Ferrule the other with a 14mm Ferrule. Both tips are the same hardness and both are shaped to a dime radius.
Now stroke the cue such that at the instant of contact both cues are traveling at 15 ft/sec.
Does the smaller tip exert less force on the CB than the larger tip?
The rational that it might is that there is less "leather" behind the smaller tip to generate the forces involved. The rational that it might not is that there is enough "leather" to generate the forces and that extra leather does nothng more.
Mitch,
This line of thinking is akin to: "Which is heavier - a pound of feathers or a pound of lead"?
If we assume the diameter of the cue tip (10 vs. 14) is the only difference, and both "points" on the cue tip's contact surfaces are dime shaped and both sticks weights are identical, we must assume the cue tip "force" of either tip will be identical, e.g., transfer identical energy to the CB.
To suggest otherwise, is to deny the laws of physics IMO.
No, consider that the force at the front of the tip causes the leather to compress. Since there is no force applied to the edge of the tip, the edge does not compress. So the question becomes, what pattern of compression takes place in the leather of the tip.
If the compression patern through the leather is a column of constant radius, then it maters not. Both tips will feel the same.
If the compression patern through the leather is a cone from the point of contact towards the ferrule and tenon; then there comes a point where, if the tip is small enough in diameter, that the compression cone extends past the edge of the ferrule; and at this point, the shaft with the smaller ferrule WILL feel a softer hit than the shaft with the larger ferrule--because the tip just lost the ability to transmit as much force as the larger diameter one. So then, here, it maters what the shape of the cone is, acute or oblate.
So the question is what shape is the compression: a column or a cone--my guess is that it is conical in shape--I just don't know if the shape is acute or oblate.
I disagree.
There IS always going to be force applied to the edge. This is evident by virtue of the mushrooming that always results from impact. Like anything malleable, the distortion will be primarily effect the axis of the tip - but it will be transferred to the base and ferrule laterally as well. This is evidenced by what we call "mushrooming."
Some tips are so hard, they have minimal elasticity and therefore minimal mushrooming. Likewise, soft tips have greater compression and lots of mushrooming from repeated impacts.
Mushrooming can be minimized, but never eliminated. Think of a malleable bullet. When it strikes a harder object, all the axial energy transforms to lateral expansion.
Unless you're tip is ceramic, lateral expansion is always present.
How things "feel" is interesting. But how things actually are - is everything!
Ok, you disagree, well then why does my hard tip on my 134 feel harder than my hard tip on my Z2?
as in significantly harder, a difference larger that the typical distributioin of tip harnesses within a single grade of harness.
I would never debate what you subjectively "feel."
But THAT - does not dismiss the objectivity - of the physics involved.
Ever shoot a ceramic bullet ;-)
Yes, in a slingshot.
Optimal Cue Tip Diameter
- Title: Optimal Cue Tip Diameter
- Author: Zeke (Ken Secor)
- Published: 9/4/2012 12:23:54 PM
