Carbon Fiber vs Maple - Density and Squirt

[Patrick Johnson]

Just because I was curious, here's a simple diagram of the cross sections of two 12mm shafts, carbon fiber and maple, showing the thickness of CF walls needed to equal the mass of the equal diameter maple shaft (for CF that's 2.5 times as dense as maple, which Google says is more or less typical).

Since the primary factor in squirt is end mass, I wonder if these create the same amounts of squirt.

pj
chgo

 

[iusedtoberich]

That's a good question. I'd bet inertia plays a part, which is dependent on the distribution of mass from the center.

Anecdotally, 12mm solid wood shafts (with ferrules), were NOT low deflection by any means. On the other hand, most CF shafts are at least "medium" deflection, and the higher tiered ones are low. I'm not sure of the wall thickness of them.

 

[DeeDeeCues]

That's a good question. I'd bet inertia plays a part, which is dependent on the distribution of mass from the center.

Rotational Moments of Inertia are dependent on mass distribution. Simple inertia is not affected by mass distribution. While one could argue that the cue is rotating about it's center of mass in this example, I don't think any one would argue that it is rotating along the axis shown.


In this example, the stiffness would affected by the mass distribution.

 

[Patrick Johnson]

I'd bet inertia plays a part, which is dependent on the distribution of mass from the center.

You mean the distribution of mass along the cue’s length? As others said, I think it’s all about the mass in the first several inches at the tip, not its distribution along the entire length.

pj
chgo

 

[jondrums]

I think its both lowest mass and highest stiffness that matters. Something like the resonant mode

 

[Mensabum]

Just because I was curious, here's a simple diagram of the cross sections of two 12mm shafts, carbon fiber and maple, showing the thickness of CF walls needed to equal the mass of the equal diameter maple shaft (for CF that's 2.5 times as dense as maple, which Google says is more or less typical).

Since the primary factor in squirt is end mass, I wonder if these create the same amounts of squirt.

pj
chgo

View attachment 860974

Does anybody know the thickness of walls on popular cf shafts??

 

[iusedtoberich]

Rotational Moments of Inertia are dependent on mass distribution. Simple inertia is not affected by mass distribution. While one could argue that the cue is rotating about it's center of mass in this example, I don't think any one would argue that it is rotating along the axis shown.


In this example, the stiffness would affected by the mass distribution.

I actually was thinking of the rotation about the squirt angle, not the rotation as in twirling the cue in the grip hand. But now that you wrote out what you did and I thought about it more, I guess the distribution of mass on a hollow vs solid design would not make a difference with the rotation with respect to the squirt rotation?

 

[Vahmurka]

Does anybody know the thickness of walls on popular cf shafts??

Seems to vary between 0.7 and 1.2 mm.
"Some break cues or specific heavy-duty shafts may have thicker walls, up to 1.5mm or more, for added stiffness and durability"

 

[DeeDeeCues]

I actually was thinking of the rotation about the squirt angle, not the rotation as in twirling the cue in the grip hand. But now that you wrote out what you did and I thought about it more, I guess the distribution of mass on a hollow vs solid design would not make a difference with the rotation with respect to the squirt rotation?

Yeah, wouldn't really be a consideration, especially given the parameters that the cross-sectional mass is the same.

 

[Not Dead Ted]

Just because I was curious, here's a simple diagram of the cross sections of two 12mm shafts, carbon fiber and maple, showing the thickness of CF walls needed to equal the mass of the equal diameter maple shaft (for CF that's 2.5 times as dense as maple, which Google says is more or less typical).

Since the primary factor in squirt is end mass, I wonder if these create the same amounts of squirt.

pj
chgo

View attachment 860974

While I cannot vouch for the accuracy of this beam deflection calculator: https://www.engineering.com/resources/beam-deflection-calculators/

or the appropriateness application to this problem, there appears to be an order of magnitude difference in favor of the CF.

I used CF shaft wall thickness .04 inches, 4" length, .5" diameter for hollow tube deflection, and for wood, thickness .5", length 4".
Applied 1 pound stress to both.

The problem is that most CF shafts are stuffed with something, and may behave more like a solid structure rather than a tube.

 

[Patrick Johnson]

While I cannot vouch for the accuracy of this beam deflection calculator: https://www.engineering.com/resources/beam-deflection-calculators/

or the appropriateness application to this problem, there appears to be an order of magnitude difference in favor of the CF.

I used CF shaft wall thickness .04 inches, 4" length, .5" diameter for hollow tube deflection, and for wood, thickness .5", length 4".
Applied 1 pound stress to both.

The problem is that most CF shafts are stuffed with something, and may behave more like a solid structure rather than a tube.

If that measures stiffness, I don't think it matters much for a squirt comparison - squirt is generated primarily by end mass, not stiffness.

pj
chgo

 

[garczar]

While I cannot vouch for the accuracy of this beam deflection calculator: https://www.engineering.com/resources/beam-deflection-calculators/

or the appropriateness application to this problem, there appears to be an order of magnitude difference in favor of the CF.

I used CF shaft wall thickness .04 inches, 4" length, .5" diameter for hollow tube deflection, and for wood, thickness .5", length 4".
Applied 1 pound stress to both.

The problem is that most CF shafts are stuffed with something, and may behave more like a solid structure rather than a tube.

agree. its REALLY hard to compare a cf tube(filled or unfilled) with a solid 'rod' of maple wood.

 

[garczar]

Does anybody know the thickness of walls on popular cf shafts??

a while back this topic came up and i checked a few tube suppliers and only a few mentioned wall thickness. here's one that did but i don't know if that thickness is constant over the entire length. https://hhbcarbon.com/products/124m...shaft-pro-taper-carbon-cue-shaft-blank-hollow i know golf shaft tubes are thinner at the fat end than the tip. I'd assume a cue shaft would be similar.

 

[Not Dead Ted]

If that measures stiffness, I don't think it matters much for a squirt comparison - squirt is generated primarily by end mass, not stiffness.

pj
chgo

I get mass for a carbon fiber tube with outer radius 6mm, 1mm thickness and 4cm long to be .96 g, maple cylinder solid, 3.16 g.

But, once you stuff the CF tube, things change.

 

[Patrick Johnson]

I get mass for a carbon fiber tube with outer radius 6mm, 1mm thickness and 4cm long to be .96 g, maple cylinder solid, 3.16 g.

But, once you stuff the CF tube, things change.

Thanks for the info. FYI, with those dimensions*, the CF walls occupy about 31% of the total 12mm shaft's cross section area.

pj
chgo

*(Assuming "outer radius 6mm" means overall diameter = 12mm.)

 

[Mensabum]

a while back this topic came up and i checked a few tube suppliers and only a few mentioned wall thickness. here's one that did but i don't know if that thickness is constant over the entire length. https://hhbcarbon.com/products/124m...shaft-pro-taper-carbon-cue-shaft-blank-hollow i know golf shaft tubes are thinner at the fat end than the tip. I'd assume a cue shaft would be similar

I wonder if the foam density can affect thickness?? Would you need as thick a wall with hard foam reinforcement behind it??

 

[kollegedave]

Just because I was curious, here's a simple diagram of the cross sections of two 12mm shafts, carbon fiber and maple, showing the thickness of CF walls needed to equal the mass of the equal diameter maple shaft (for CF that's 2.5 times as dense as maple, which Google says is more or less typical).

Since the primary factor in squirt is end mass, I wonder if these create the same amounts of squirt.

pj
chgo

View attachment 860974

The last science class I took was in undergraduate school and I am now 46, so I will leave the scientific theory to people with more expertise. I can offer up an opinion on using carbon fiber vs. wood that is anecdotal, as I have played with a cuetec cynergy since 2020 but before then I was using wood.

When I hit the very first ball with my cynergy, I noticed that it traveled further than with my wood shaft. I have speculated that this is maybe because wood might compress very slightly whereas maybe the CF does not, so maybe energy is more efficiently transferred to the cue ball? That's my hypothesis. I would characterize the cynergy shaft as producing a turbo charged cue ball and a reduced amount of squirt, but it still squirts.

I have hit a few balls with the mezz ignite and the predator revo after I had already purchased the cynergy. Both of these shafts seemed to produce less squirt (the predator was significantly less), but I didn't notice the supercharged cueball effect that I feel with the cynergy. I have a buddy that plays with a revo, and he said that while there is less squirt, you have to contend with pretty serious spin induced throw once the cue ball gets to the object ball. Everything has a cost.

kollegedave

 

[garczar]

The last science class I took was in undergraduate school and I am now 46, so I will leave the scientific theory to people with more expertise. I can offer up an opinion on using carbon fiber vs. wood that is anecdotal, as I have played with a cuetec cynergy since 2020 but before then I was using wood.

When I hit the very first ball with my cynergy, I noticed that it traveled further than with my wood shaft. I have speculated that this is maybe because wood might compress very slightly whereas maybe the CF does not, so maybe energy is more efficiently transferred to the cue ball? That's my hypothesis. I would characterize the cynergy shaft as producing a turbo charged cue ball and a reduced amount of squirt, but it still squirts.

I have hit a few balls with the mezz ignite and the predator revo after I had already purchased the cynergy. Both of these shafts seemed to produce less squirt (the predator was significantly less), but I didn't notice the supercharged cueball effect that I feel with the cynergy. I have a buddy that plays with a revo, and he said that while there is less squirt, you have to contend with pretty serious spin induced throw once the cue ball gets to the object ball. Everything has a cost.

kollegedave

agree on the energy transfer. with every cf shaft i've tried i found it easier to drive the cb forward. squirt varied from brand to brand but easy power was a constant.

 

[garczar]

I wonder if the foam density can affect thickness?? Would you need as thick a wall with hard foam reinforcement behind it??

From what i've dug up the foam is used for two reasons: final weighting and sound/vibration control. Without some type of filler the shaft would be way too light and would ring/ping like a bell. CF is incredibly stout, i don't think the foam does much to increase strength.

 

[iusedtoberich]

The foam "should" help the overall strength somewhat, to prevent buckling of the thin wall. How much, IDK. It might be .01%, or might be 5%. I'd take a pure guess at no more than 5% in our application.