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Unread 08-01-2012, 11:59
NJEchoAlpha NJEchoAlpha is offline
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Ball balance

Testing with the FRC foam balls, they appear to be imbalanced in terms of density. Will this be corrected for the competition or will we just have to compensate for the inaccuracy of the balls we are testing with?
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Unread 08-01-2012, 12:07
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Re: Ball balance

The density is random. No two balls will be exactly alike.
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Unread 08-01-2012, 12:13
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Re: Ball balance

Al- we've found the density of new balls to be extremely consistent.

If you have a ball you find particularly squishy, I'd bet money that it has holes poked in the side of it somewhere (from just tossing around, minor abrasion).

We have found that once the balls are punctured, their characteristics change dramatically.

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Unread 08-01-2012, 12:19
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Re: Ball balance

Quote:
Originally Posted by Al Skierkiewicz View Post
The density is random. No two balls will be exactly alike.
This is very disconcerting. I'll have to notify my team.
I wonder if this was intentional or not?
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Unread 08-01-2012, 13:12
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Re: Ball balance

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Originally Posted by NJEchoAlpha View Post
Will this be corrected for the competition or will we just have to compensate for the inaccuracy of the balls we are testing with?
It will not be "corrected" in my opinion, you would be wise to design flexibly.
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Unread 08-01-2012, 14:38
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Re: Ball balance

Do you have the weight for a handful of the balls measured accurately at this point? Also, are they very accurately 7"?

Thanks!

-Mike
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Unread 08-01-2012, 16:31
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Re: Ball balance

At least one of the three balls from our KOP has a bump on one side. These are simply (read 'cheap') foam and prudence would suggest that no two are alike.
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Unread 08-01-2012, 17:06
Jim Wilks Jim Wilks is offline
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Re: Ball balance

We noticed the same and gave one a "floatation test" in a sink. One side always came to the top. These are cheap balls and vary considerably in balance.
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Unread 14-01-2012, 00:11
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Re: Ball balance

So how does this compare to the balance of density of poof balls?
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Unread 14-01-2012, 00:26
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Re: Ball balance

We live in an imperfect world.
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Unread 14-01-2012, 07:43
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Re: Ball balance

We found a density difference in the balls which is part of their manufacturing. We found that the side with the injection gate is always heavier than the side without the gate. I believe it is an inherent part of the manufacturing process as the material is being injected into the mold. Once the mold has been filled the material starts to setup and the extra material used to assure a full cavity collects at the gate site causing the increased density.
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Unread 14-01-2012, 08:55
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Re: Ball balance

This is nothing new. Remember "purple side down" in 2006?
It's all part of the game challenge. Design accordingly.
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