I watched Norm Duke's tutorial videos and he mentioned how to check thumb hole fit.
He said hang the ball with fingers in on your side with no pressure. If you lift the index finger just a bit, the ball should fall off. If it doesn't, it may be too small.

In my case it doesn't. I feel a lot of friction on the side of my thumb. I also start callusing both sides of the thumb.
My thumb is kinda oval and the hole seems round.


Here is a picture of the broken blood vessel under my thumb nail.


Is what Norm talked about still a good way to check thumb hole fit?

Eric, I believe Norm's tip is a good way to see if you need to add or remove tape. After a while, you may know as soon as you insert your thumb. Also be aware that sometimes you need to change the tape on top if it the feel of texture has deteriorated.

Some words on the thumb hole and another way to check the thumb hole ...

_________________
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The short poem Desiderata contains words of wisdom for us all.
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John