J_w73 you probably grab the ball with your thumb when you cup your wrist. Don't do that. Instead, just press the fingers into and slightly under the ball, while keeping your thumb relaxed.

I see a lot of people grab the ball with both their fingers and thumb when I tell them to try to get under the ball. When I show them how to just scoop the ball with their fingers and keep their thumb relaxed, the ball comes off their hand without problems.

J_w73, assuming your ball is drilled and sized properly, your thumb will come out of the ball in the downswing when your thumb is at a right angle or 90 degrees from the floor. Or, as you noticed in your trial, when your thumb is pointing straight down.

Swing your ball and release it into a overstuffed chair to watch your release, or on the floor rug, into some pillows to stop it.

Stay away from windows.

I still don't fully understand the thumb locking onto the thumb hole. Either that or I just don't have it. Something that kinda has me wondering is if I insert my thumb and pull back/out a bit it "hangs", and if I leave it like that(feels really weird) my thumb is stable in that spot during the swing. It doesn't always "hang" but if I pull my thumb out like that I'll get a similar result each time.

I was looking at that too.. When I c*ock my wrist it feels like it does make me put pressure on my grip.

thanks for the help.. I think my thumb is ok and working the way it is supposed to.. I think I solved the problem that was making my game go down hill.. I'll describe in a new post

jw73, i wanna know what you've done for thumb slippage as i have it too. i'm a little over 3.5" span with 1/2" forward and the thumb slips a good half inch till it's pinned between the back of the hole and the bevel (or lack thereof).

Well a couple of things.. I moved the tape from the back of my thumb hole to the front of my thumbhole. I was using white tape in the back and couldn't have a really tight hole or I would hang up.. I was even hanging up with the hole when it was loose..

funny thing is .. with the tape in the back my thumb would feel snug with 2-3 pieces of tape..
when I moved the tape to the front I had to put in another 3 or 4 to get it snug.. maybe it was just the contour of my thumb...

but to fix the slippage I just made a tighter thumb hole.. I'm still getting used to it though.. I have also gotten comfortable with a little bit of slippage when my thumb is a tiny bit loose but too tight with another piece of tape..I am confident that i am not going to lose the ball so I just go with the bit of slippage..
I want to try the magic carpet or other similar thumb product.. I used to make my own foam that would go in the back of my thumb hole.. kept the thumb nice and snug but would give enough to release the thumb when needed..

not really related to the slippage but the hanging.. i have notice the tape in the front is more comfortable for me as it gives my thumb a nice cushion to sit on and also gives me a little gap between the edge of the thumb hole and my thumb.. helps me clear the edge on the way out..

i may try to put the tape on the back but with a slick piece of black tape in the back.. to see how that feels.

sorry for rambling.. your answer should be in there somewhere.. if not pm me and I'll be happy to answer all your questions.

I definitely recommend black tape in the back - putting 3-4 pieces of white tape in the front actually affects the pitch and span of the ball, making it a little more stretched and reverse. If you can find it, the Ebonite black tape is much better than the red box.

I would also recommend the black on the back of the thumb for a couple of reasons. The white, cloth backed tape in the front, does provide some thumb friction that may cause some thumb squeezing. While, the smooth black tape on the back straightens your thumb out so et exits cleanly without grabbing.

Secondly, I have found that some white tape adhesives ooze out with repeated use in the thumb hole, and is difficult to remove. It then becomes sticky in the hole so you could hang up.

If I would sweat, I would sweat on the pad of my thumb, not on the nail.

There is a product by Shur Hook (people who make the cork thumb inserts), that is essentially a piece of thicker teflon for the back of your thumb hole. I love this stuff and can really help reduce friction on the top of your knuckle but give you a nice tight secure thumbhole.

I tried to find a link to it online, but only found the main distributors link for pro-shops. I can take a picture of it when I am at the alley tomorrow.