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Author Topic: which span to use for thumb angle conversion chart  (Read 2371 times)

joedi

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which span to use for thumb angle conversion chart
« on: August 05, 2021, 06:18:46 AM »
Hi,

as this is my first post I first of all would like to thank the forum and all of its users for the many good articles in here which I am reading since quite a while!!

I am trying to evaluate my ball fit. One step is to use the famous "thumb angle conversion chart" which can be found at https://innovativebowling.com/assets/images/Thumb%20Angle%20Conversion%20Pitch%20Chart.pdf.

As there are many definitions of "span", I am curious which one to use here?
- thumb hole to ring finger hole? Or is the index finger relevant?
- thumb hole to bridge?
- thumb hole to center of ring or index finger hole?
- thumb hole to middle of second ring or index finger segment?

Some assumption:
Using the cut to cut doesn't make much sense, as it differs if using inserts or not. So finger hole means the hole inside the insert if one is used of the whole drilled if none is used.
Measuring from the thumb hole edge to ring finger hole edge makes most sense to me, but I am not sure.

Any help appreciated!

 

king of the mill

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Re: which span to use for thumb angle conversion chart
« Reply #1 on: August 12, 2021, 08:47:26 AM »
Take the average of your full inside edge to edge spans.
not gonna be here long, just dusting out the message bin...

enjoy me while i last

joedi

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Re: which span to use for thumb angle conversion chart
« Reply #2 on: August 18, 2021, 05:09:00 AM »
Found the same question in another forum where the author claimed that he found the answer somewhere in the internet - unfortunately not mentioning where:
The span for the Morich's fitting instructions is the span of the middle finger.

So as inserts and exchangeable inserts would have significant effect on the cut to cut length, I finally conclude that:
Finger hole to finger hole span must be used.

I will try to live with this assumption.

ccrider

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Re: which span to use for thumb angle conversion chart
« Reply #3 on: August 28, 2021, 07:15:39 AM »
Is “forward” still considered towards the palm?