So I've been struggling with something lately, hopefully someone can shed some light on this subject for me.

BTW:All thoughts are based on the premise that CGNOMADDAH

Why does pin position matter?  And pin length?  If a symmetric ball is the same everywhere, and CGNOMADDAH, shouldn't the ball do the same thing every single time regardless of layout?

Would you mind defining major axis for me?

The pin sits in a vertical axis through the core, it marks the "top" of it.
If the pin was exactly above the core and if this was located in the ball's center, then we would have a ball without a CG deviation from the pin - it would be even-weighted. But this is not the case - production irregularities and purpose shift the core off of that "perfect centerline. That's where the CG comes from and needs to be marked, because it is a weight distribution shift. If it is vital to the balls recation or not, is a different thing, it is, at least, important for legal weights and tells you what you can make out of a ball with the setup.

Besides, the pin is important for the drilling. Remember that a core wants to spin and stabilize around a certain preferred spin axis (PSA) once it rotates freely. These are the main axis' of the core, and the pin nominates the main or vertical axis. In fact, the difference the weight distribution between this main axis and the 90° secondary axis to it defines the core's differential, and way you "post" the core through the relative pin postion to your initial rotational axis during the release (your PAP - surprise! ) through the drilling, you define the amount of flare the ball shows through the core's migration towards its PSA.

Sounds complicated, but that's in technical nutshell why the pin is important, as well as your PAP and what (and how much) makes a ball flare. And, as a side effect, you can see where the CG comes from.
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DizzyFugu - Reporting from Germany

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In a correctly drilled ball, the PSA of a strong MB ball is in the marked MB axis, which is 90° to the pin (which makes its location 6.75" from the pin).
In a weak mass bias ball - and it can have a symmetrical or asymmetrical core, thsi is a wide misunderstanding! - the PSA is at a "virtual" point or area which lies in a direct line of 6.75" from the pin through the CG. It has a mass bias, through the core shift, but it is rather weak. A mass biased that has been designed into the core through shape or weight will override this "effect", so better use the PSA marker if the ball has one. In this case, the CGNOMADDAH statement is 100% correct.

That said, if the ball is not drilled properly or the PAP shifts over time, it can happen that the ball migrates towards the pin. This can happen if the ball is initially drilled with the core in a leverage position (which is half way betwenn PAP and pin, at 3 3/8") and somehow the pin moves closer to the PAP - e. g. thorugh a lowered track. Such a ball will have a much smoother hook and a very reduced back end reaction, even hitting weak. I have seen this happen for some low trackers around here who wanted a strong ball reaction - and received more or less the opposite.
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DizzyFugu - Reporting from Germany

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Edited on 5/19/2008 10:02 AM

Yup!
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DizzyFugu - Reporting from Germany

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