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Pin to cg distance

Posted: December 26th, 2018, 3:58 am
by poloidrogo
Hi guys I just got a new Roto Grip Idol as a Christmas present, but I notice that the pin to cg is around 1 inch distance, what is the reason some balls have 3 or 4 inches distance and this came to short. Do you think it will afect being to short ??

Thanks in advance

Re: Pin to cg distance

Posted: December 26th, 2018, 4:16 am
by EricHartwell
Pin in or short Pin to Cg balls used to be very limited in how you could drill them. With the rules today allowing more static weight imbalance allows for more drilling versatility with such balls.

What is the top weight?

Re: Pin to cg distance

Posted: December 26th, 2018, 7:57 pm
by bowl1820
poloidrogo wrote: what is the reason some balls have 3 or 4 inches distance and this came to short.
It's do to manufacturing variance, Basically all the parts used to make a ball have tiny variations in them (densities ,size etc.) and each step in making it has slight variations/errors in them. They all add up and they cause the cg (which the center of gravity is not the actual geometric center of the ball) to move some and you wind up with different pin to cg measurements.

There's a article wrote by Nick Siefers called "MANUFACTURING PROCESS VARIATION: THE SMALLEST of SHIFTS CAN ALTER PIN DISTANCE and TOP WEIGHT" that explains it in detail.

"MANUFACTURING PROCESS VARIATION: THE SMALLEST of SHIFTS CAN ALTER PIN DISTANCE and TOP WEIGHT"
http://www.itbca.bowlingknowledge.info/ ... top-weight

Re: Pin to cg distance

Posted: December 27th, 2018, 10:24 am
by poloidrogo
EricHartwell wrote:Pin in or short Pin to Cg balls used to be very limited in how you could drill them. With the rules today allowing more static weight imbalance allows for more drilling versatility with such balls.

What is the top weight?
Hi Erick the top weight is 2.55

Thanks

Re: Pin to cg distance

Posted: December 27th, 2018, 10:00 pm
by EricHartwell
poloidrogo wrote:
Hi Erick the top weight is 2.55

Thanks
With 3 oz of imbalance to work with this will not limit layout choices.