Question for Dr.Dave

nodeflection

AzB Silver Member
Silver Member
I doesn't effect anything. He posted everything you need to know videos and this isn't a question covered.
 

ShootingArts

Smorg is giving St Peter the 7!
Gold Member
Silver Member
good questions and one more!

How does the percentage of phenolic affect the coefficient of restitution of pool balls
and how many times has this changed over the years? To possibly have an answer
just count good quality ball sets from Sulac or Brunswick.To narrow the number
of years lets say from 1970 to present.I read some place the Cyclop balls are 85%
phenolic and how does this differ from Aramith balls?



I have wondered about your first question, mainly how it applies to mixed sets and cue balls that don't match the set.

A third question applies to particularly sets of balls in pool halls. Most halls stack the racks of balls so the top sets get played much more often than sets lower in the stack. Do those top sets of balls that get used hours a day every day snap back the same as the balls with comparatively little use? Obvious subquestion, do balls lose some of their snap as they age?

I bought a fairly cheap set of balls. I was amazed how much better they played than the balls at a quality pool hall.

Hu
 

Bob Jewett

AZB Osmium Member
Staff member
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How does the percentage of phenolic affect the coefficient of restitution of pool balls and how many times has this changed over the years? To possibly have an answer just count good quality ball sets from Sulac or Brunswick.To narrow the number of years lets say from 1970 to present.I read some place the Cyclop balls are 85% phenolic and how does this differ from Aramith balls?
For a material property like that, I think the only way you are going to find out is to do some testing. I think it will depend on exactly what is added, how much is added, how it is mixed, the exact proportions of the parts of the resin itself, the curing additives, ....

I have never seen a ball company publish coefficients of restitution (efficiency of bouncing, abbreviated COR and usually indicated by "e" in equations).

I have heard that Aramith does tests for COR and that for some tournaments they reserve the balls from a production run that bounce the highest off a steel block.

So far as I know, Brunswick never made phenolic billiard balls.
 
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