13.2mm. I had a go at hitting some of my 2-1/4" pool balls (169gm) uzing a non-altered Eliminator shaft -- to get the feel of what pool players feel.
Dr Onoda. The balls still had markings on them from years ago, when i uzed them to peer-review some of Dr Onoda's pool physics stuff.
Kontrol. The larger heavyer (pool) balls are eezyer to kontrol than the 2-1/16" (billiards) balls (141gm).
Squirt. I reckon that 13.2mm shafts are too squirty (ie too tip-heavy). I needed a bridge length of 11" for my backhandpivot tests, for slowish shots (2-1/4" balls). For more powerfull shots i needed less than 11". In theory, this pivot L suites my natural bridge L, but allthesame i don't like it.
Squirt. In regard to billiards (2-1/16" balls), i prefer my billiards cues to allow me to uze fronthandpivot, at least for softish shots -- a 9.0mm shaft uzually duzz the trick. Just for interest, uzing a 13.2mm Eliminator, for backhandpivot, for softish shots, I needed a bridge L of 6".
12.0mm. If i played pool i might uze 12.0mm or even 11.5mm. I wouldn't uze hollowed shafts -- i would prefer to uze solid maple, allbeit praps 0.5mm thinner if need be, rather than hollow.
20oz. Iz too light for 169gm balls. If i played pool i might uze a 25oz cue (Eliminator of course).
24.1mm. I suspekt that poolcue midjoints are too small -- they shood be say 25mm or 26mm. I reckon this would allow u to hav a say 11.5mm tip diameter, and a parallel taper, while retaining cue-power. Hell, some snooker cues hav 24mm midjoints, for piddly little 141gm balls.
Nickel Dime. The LePro qtips had a 10mm radius -- this woz good for skrew and side.
I flattened one tip to about a 20mm radius -- this woznt very good for skrew and side (alltho it in effekt reduced squirt a bit).
If i uzed a 12mm diameter shaft, praps i would prefer a tip radius a bit less than 10mm, eg 9mm.