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Unread 05-02-2012, 22:33
JMR15RTC JMR15RTC is offline
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BALL DENSITY

Has anyone else noticed alot of variation in the density of the balls. When we shoot with all variables the same on the shooter some of the balls shot vary a great deal in distance. Our shooter is back to full speed for each shot and nothing else has changed. We are thinking it is a difference in the density of the balls. Anyone else have any thoughts? Thanks!
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Unread 05-02-2012, 22:49
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Re: BALL DENSITY

The biggest issue seems to be that the new ones have a skin and almost hold air like a regular rubber ball. after some handling, the skin gets lots of little holes and the ball compresses much easier and more quickly.
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Unread 06-02-2012, 15:58
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Re: BALL DENSITY

We tested, and the balls are varying slightly in weight and the weight is not evenly balanced throughout the ball.
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Unread 06-02-2012, 16:18
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Re: BALL DENSITY

Yes, we measured the three from the kit and two others we got from AndyMark and they vary about 20%. It is very frustrating.
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Unread 06-02-2012, 17:43
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Re: BALL DENSITY

We noticed that a few of the balls compressed a lot more than others and thus it's going to be interesting to see which teams can handle that and which can't. This is all very frustrating.
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Unread 17-02-2012, 13:55
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Re: BALL DENSITY

We had the same experience. We had three roughed up balls and one new one. The three shoot well but the new one launches with twice the distance
At the regionals they will probably start out with new balls which will gradually soften until one is destroyed and they put in a new one. That will be fun........NOT
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Unread 17-02-2012, 14:42
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Re: BALL DENSITY

Quote:
Originally Posted by JMR15RTC View Post
Has anyone else noticed alot of variation in the density of the balls.
What you describe is not a variation of density. The ball is still roughly the same volume and mass.

The title of the thread should be "Coefficient of Restitution"

Google it.


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Unread 17-02-2012, 20:41
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Re: BALL DENSITY

This is one of the challenges of this game. The best way to get away from this is to design a shorter that takes this problem out of play. Almost everyone with a wheel shorter is going to have a problem with this.
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Unread 17-02-2012, 20:48
Tom Ore Tom Ore is offline
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Re: BALL DENSITY

We toyed with the idea of putting in a piston to squish the ball and measure deflection and then changing wheel speed to suit each ball.
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