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Author Topic: Properly measuring center of grip for dual angle  (Read 8933 times)

lefty50

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Properly measuring center of grip for dual angle
« on: May 16, 2019, 11:37:39 AM »
Apologies in advance for the question, but it's bothering me and may throw off my results slightly, so before I start measuring everything I currently have, I need to ask...

How do I measure for center of grip? If I draw a line straight between bottom of fingers and draw the center line perpendicular to that, it falls off towards the left side of my thumb. If I draw a line from center of thumb up thru fingers, the line will not be centered between the fingers. The lines are slightly off from each other, which will affect the measurements.

Which is correct?

Thanks in advance

 

Impending Doom

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Re: Properly measuring center of grip for dual angle
« Reply #1 on: May 16, 2019, 11:49:05 AM »
You don't need to know your span for dual angle. It's based off of your pap. After you've laid out your drill angle, pin to pap and Val angle, you then just go from that point and find the center of the grip.

lefty50

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Re: Properly measuring center of grip for dual angle
« Reply #2 on: May 16, 2019, 12:24:03 PM »
Agreed and thanks, but I think the question is still valid since part of finding your PAP on a measured ball is based from the center line, which, as I am looking at it, varies slightly depending on the answer to the question.  :)

MI 2 AZ

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Re: Properly measuring center of grip for dual angle
« Reply #3 on: May 16, 2019, 12:46:11 PM »
Lefty50, are you trying to reverse-engineer the dual angles on an already drilled ball?

If so, just measure from the average of the difference between the two finger holes.  The slight difference is probably not critical for finding the PAP. 

It seems to me, that my PAP varies from ball to ball but that might just be my own inconsistencies.  :)
« Last Edit: May 16, 2019, 12:51:32 PM by MI 2 AZ »
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lefty50

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Re: Properly measuring center of grip for dual angle
« Reply #4 on: May 16, 2019, 01:13:57 PM »
Yes, checking a drilled ball. Avg the difference... sounds good. That's actually what I've done in the past, but was hoping to figure out was everyone does. You are right though, if I avg the difference, the result should be close enough for govt work unless I know absolutely sure the accepted standard..... As for PAP different on each ball, you are correct AFAIK. In fact, a recently drilled ball was way different than what was previously measured. Went from 4-3/4 by 1/2 to 4x1. Hence my previous post called "flare in the air", which is a real phenomenon, at least for asym. I haven't proven it on sym yet, but that's another topic.

joedi

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Re: Properly measuring center of grip for dual angle
« Reply #5 on: August 05, 2021, 06:59:34 AM »
If you want to find the "center of grip" on a drilled ball you must
- draw a bridge line between the centers of you finger holes (shortest connection between the drilled finger holes)
- mark the middle of this line (bridge center)
- draw a line between the bridge center and the center of your thumb hole (grip center line)
- measure the middle of this line and there is your "center of grip"