The span is cut to cut or center to center ?

Full spans are gripping surface to gripping surface.  Cut to cut spans are used by the driller to tell him where the pilot holes for the grips and/or slug are placed to obtain the correct full spans.  I don't use center to center spans at all, other drillers might but I don't know what for.  --  JohnP

My driller drilled my ball this evening, but I didn't get to try it as 38 lanes in this 40 lane house were full of league bowlers and the 2 vacant lanes they had, they reserve them in case a league bowler's lane breaks down.

Anyhow, he used 30* to drill the thumb to finger angle.

He drilled the thumb at 0 F/R and 9/16 out (left) lateral as on my regular grip I had 1/16 out lateral, so he added 1/2" to that. He drew a line from the thumb thru the ring finger to establish the 2nd Anatomical center line (thumb)

He added 1/8 reverse to fingers and the span fit seems good with pad of fingers properly seated on grips and not having the finger nails  touching the back of the grips.

To the best of my knowledge, my driller followed the instructions perfectly

I don't know if I will get a chance to try the ball Tuesday or not as I have league Tuesday. Might be able to try it after league. I will try throwing it 1or 2 times when throwing warm-up balls for league.

The ball feels good other than the gips are not quite as comfortable turned to the right to match the fingers being turned to the right. When I back them off a wee bit  to the left  from that position, they feel better, but then that would be partially defeating the angle the fingers were drilled, I think, but could be wrong there.

I will report again oncne I have had a chance to throw it.

The key to the best and appropriate feeling of the inserts is to match the curvature of the top of the finger to match the curvature of the insert.  If the measured angle is done correctly, there will be a marginal adjustments based on the uniqueness of the fingers.  But, you want this to feel good.

Thanks Joe ... That is what I will do. My fingers felt a bit twisted when the front side of grips was matched up to the direction the finger holes were drilled, but when I backed them back left a bit similar to what you said to do, it was way more comfortable.

For me and the people I drill for, the feel of the thumb is extremely important. To the point of if the customer isn't 100% satisfied with the feel/fit I trash can that thumb and do it again. I do the same for all of my customers as I do for my self.As to the pitch and oval of the thumb,I come to the conclusion that the degree of oval stays the same on the ADT layout at least for me. I've tried lining up the Oval with the center of my ring finger and that locked in my thumb to much. My thumb is very tight and conforming in my thumb slug, so my angle of degree hadsno variance .For me it was better to line up my IT thumb in a straight line with the center of my grip

Received Email from Joe on my question advising to reduce drlling angle to 23-25 degrees, so that should take care of that problem ....  Thanks Joe.

I am getting questions about the "extreme" use of lateral pitch in the Anatomical Drilling Technique.  Here is the anatomical rationale for why we want to use a significant amount of lateral. At the base of the thumb, into the palm, is a collection of 4 muscles.  This muscle mass, the thenar eminence, allows for all of thumb movements.  For our purposes, it is vital to understand how lateral movement of the thumb changes tension in and the height of this muscle mass.  To see and feel this, start with your palm facing up.  Notice where the thumb is located and how relaxed the wrist is as well as low this muscle mass is on the hand.  Now with your palm up, move the thumb toward the center of your hand.  Notice the change in tension as well as height of the muscle mass relative to your hand.  Due to this anatomical truth, significant lateral pitch will aid in getting the ball to sit on the ball on the hand better as well as reducing tension in the thumb and wrist.

Other than 3 or 4 tosses down the lane before league Tues, I haven't been able to try mine to judge it fairly yet. I didn't want to let the team down, so I didn't try it during league. It has been spring break for school kids here this week and the bowling lanes have been packed and I mean packed with kids all week, so there have been no open lanes to practice on. I don't know about evenings as I don't venture out at night.

There is a morning league this morning so the house will be open early. I have some errands to run and if finished in time, I will try to get in a couple games of practice with the ADT grip.

I will say one thing though and that is I LOVE the way it feels in my hand, so hope I will be able to bowl with it.

Very interesting. I don't drill my stuff like most of you here do, so I doubt I'll be able to have my current driller do this ADT drill for me. Plus, I'm just a league bowler with maybe 4 to 8 tourney's a year. If I was a bit more into bowling, I'll prolly seek a driller who can do this for me.

But, it's interesting to see the reaction from others who tried it.....