No thumb rule change.

May i make a small observation or rather everybody make one.

When was the last time you saw the TBA check a ball at an event, be it league, state or national level?


Junior Nationals; 298, 299, 300 games; when someone raises a dispute; random checking.

It does occur; believe it or not. (just not as much as it should).
 
To make it fair I do believe the point that CT is making would make it policable.

Draw a line across the finger hole cuts, then draw a line perpendicular from the bridge center through where the palm would lay on the ball, and nominate a distance to be the CG for all thumbless bowlers.

Rulling out balance holes would be tough.

Maybe make all drillings have the CG in the same range. Example, draw a 1 inch circle around the CG mark on the ball and thats where everybodies CG needs to be.

Take the overly off set drilling away from all bowlers to be fair for everyone.

As J.Belmo has said, the rules need some work.
 
Diverting slightly
This rule has caused some augments locally

The following tolerances will be permissible in the balance of a bowling ball used in TBA competition: Refer to Rule 127 for the penalty for bowling with a ball that is found to be illegal.
1. 10 pounds or more:
(e) A ball used without any hole or indentations may not have more than one (1) ounce difference between any two halves of the ball.

Pretty straight forward IMO
 
To make it fair I do believe the point that CT is making would make it policable.

Draw a line across the finger hole cuts, then draw a line perpendicular from the bridge center through where the palm would lay on the ball, and nominate a distance to be the CG for all thumbless bowlers.

Rulling out balance holes would be tough.

Maybe make all drillings have the CG in the same range. Example, draw a 1 inch circle around the CG mark on the ball and thats where everybodies CG needs to be.

Take the overly off set drilling away from all bowlers to be fair for everyone.

As J.Belmo has said, the rules need some work.

USBC tried to legislate that a few years ago. Problem was the manufacturers were unable to guarantee the accuracy of their marking of the CG to a degree that it could render some balls statically illegal, especially those with heavier top weight. I also believe that that legislation would have been to the detriment of those payers who don't have the heavy hands that the high rev players do. If the sport is to be made competitive for all styles, that idea could not possibly be implemented.
 
A few people have mentioned about the rule restricting layouts. In fact, not drilling a thumb allows for a far greater variety of layouts than otherwise, especially on symmetric balls. Since the PSA tends to migrate to the thumbhole on drilled syms, a major purpose of balance holes in these balls is to adjust the drilling angle of the layout. No thumbers can drill exactly the layout they want in a sym simply by placing the cg and balance hole appropriately. For a pin down drill, just put the cg above the pin.
Asyms may be treated the same way - for a pin down asym, just mark the other end of the psa, flip the layout and the cg will end up above the pin in the fingerhole area.
 
Robbie just a quick one, if you drill a ball with a usable thumb hole (no slug) and bowl it two handed would it not still be a legal ball as the static weights using the center of grip, in this instance being between the fingers, would be balanced by the balance hole (read usable thumb)?
It would be easy enough to get it legal both ways in most cases, assuming you were starting with a blank drill. Especially if TBA allow 3oz. top weight in both cases. Selecting the correct pin out and top weight before drilling becomes much more important though.
 
Balance


The following tolerances will be permissible in the balance of a bowling ball used in TBA competition: Refer to Rule 127 for the penalty for bowling with a ball that is found to be illegal.

1. 10 pounds or more:

(a) Not more than three (3) ounces difference between top half of the ball (finger hole side) and the bottom half (side opposite the finger holes).

(b) Not more than one (1) ounce difference between the sides to the right and left of the finger holes or between the sides in front and back of the finger holes.

(c) A ball drilled without a thumb hole may not have more than one (1) ounce difference between any two halves of the ball.

(d) A ball drilled without any finger holes or indentations may not have more than one (1) ounce difference between any two halves of the ball.

(e) A ball used without any hole or indentations may not have more than one (1) ounce difference between any two halves of the ball.



the 3oz rule is already there

Source http://www.tenpin.org.au/fileadmin/...d_Regulations/TBA_Rule_Book_V8.8__24-7-12.pdf
 
(c) A ball drilled without a thumb hole may not have more than one (1) ounce difference between any two halves of the ball.


If you don't use the thumb, it will be classed as a balance hole, and you are then only allowed 1 oz. top.
 
Brenton, I believe that John means Centre of Grip rather than the marked CG. My suggestion was to have the centre of grip marked at a pre-determined point on balls drilled without a thumb hole. A thumb hole wouldn't need to be drilled, however by allowing the centre of grip to measured away from the centre of the bridge then it opens up the ability to use conventional drillings. If the centre of grip was to be around 2.5" below the centre of the bridge then balls with a 3" or so pin could be used without too much issue regarding static weights. Also if the difference between the top and bottom halves was taken to 3oz then a majority of balls would be legal without having to special order balls with super low top weight and super short pins.

Another simpler solution is to leave the rules as they are now, however insert a clause that states that the thumb hole must be drilled in such a way that part of the hole touches the vertical centre of grip line and must not be drilled further than say 6 inches from the centre of the bridge. It would stop 2 handed players off setting the thumb hole and using it as a second dynamic hole, but would have little to no effect on bowlers who drill their balls in the conventional matter. It would also solve the issue of players who use their thumb on spares but not on strikes. If the rules are left as is, the thumb hole would still need to covered or used on every delivery and forcing it to be in line with the grip would alleviate all the issues off set thumbs are causing. The only other thing that may be considered if this option was taken is to limit the size/depth of the thumb hole.

There are a lot of people out there better qualified than me to talk about this subject and they need to come up with a clearer and fairer rule than what is being proposed now.

CT
 
(c) A ball drilled without a thumb hole may not have more than one (1) ounce difference between any two halves of the ball.


If you don't use the thumb, it will be classed as a balance hole, and you are then only allowed 1 oz. top.
If you had the cg in the bridge of your fingers you wouldn't need a balance hole and if no thumb was drilled would that then mean it's 3oz top or 1 oz top max.

Also most balls out of the box have between 2.5-3.5oz top weight... If no holes are drilled, how can one manage to get top weight less than 1oz and meet all other tolerances. (I know however unlikely, it's still possible)

Just as a side note, my son is a 2 handed bowler (no thumb) I've just checked the weights on one of his balls which doesn't have a balance hole and measured the weight from the grip centre assuming the thumb hole is used and also measured it from the bridge of the fingers being centre of grip. The ball has a 3" pin to CG distance and the span is 3.5" with the "thumb hole 3/8" offset to the right. The CG in the first instance is in the CoG and the static weights are 0oz side and 1/8oz thumb weight. With the CoG measured from the bridge the side weight remained the same but thumb weight increased to 1/2oz.

In the event that a 2 hander has 0 fwd/rev pitch and the same L/R pitches then the one ball could be used as a pin over or pin under drilling...
 
A few people have mentioned about the rule restricting layouts. In fact, not drilling a thumb allows for a far greater variety of layouts than otherwise, especially on symmetric balls. Since the PSA tends to migrate to the thumbhole on drilled syms, a major purpose of balance holes in these balls is to adjust the drilling angle of the layout. No thumbers can drill exactly the layout they want in a sym simply by placing the cg and balance hole appropriately. For a pin down drill, just put the cg above the pin.
Asyms may be treated the same way - for a pin down asym, just mark the other end of the psa, flip the layout and the cg will end up above the pin in the fingerhole area.
I'm glad you are their to drill up my gear. I don't have a clue what all that means. Lol
 
Got an email from TBA yesterday to say that the rulebook has been updated several times since 2012, so either there was a dodgy link or I was loading up a cached copy somehow. They also confirmed that the rule is to be updated shortly. The rulebook accessible from the TBA front page is current as at April 2014. The current rule is as follows:


RULE 603 DRILLING SPECIFICATIONS
VERSION 10.2 – 2-4-14
32
Holes
The following limitations will govern the drilling of holes in the ball:
1. Holes or indentations, not to exceed five (5), for gripping purposes.
2. One hole for balance purposes not to exceed 1 ¼ inch in diameter.
3. No more than one (1) vent hole to each finger and/or thumb hole not to exceed ¼ inch in diameter.
4. One mill hole for inspection purposes not to exceed 5/8 inch in diameter and 1/8 inch in depth.
Any hole that cannot be reasonably shown to be used with a single hand would be classified as a balance hole.
Balance
The following tolerances will be permissible in the balance of a bowling ball used in TBA competition: Refer to Rule 127 for the penalty for bowling with a ball that is found to be illegal.
1. 10 pounds or more:
(a) Not more than three (3) ounces difference between top half of the ball (finger hole side) and the bottom half (side opposite the finger holes).
(b) Not more than one (1) ounce difference between the sides to the right and left of the finger holes or between the sides in front and back of the finger holes.
(c) A ball drilled without a thumb hole may not have more than one (1) ounce difference between any two halves of the ball.
(d) A ball drilled without any finger holes or indentations may not have more than one (1) ounce difference between any two halves of the ball.
(e) A ball used without any hole or indentations may not have more than one (1) ounce difference between any two halves of the ball.
2. Less than 10 pounds:
(a) Not more than one (1) ounce differences between the top half of the ball (finger hole side) and the bottom half (side opposite the finger holes).
(b) Not more than ¾ ounce difference between the sides to the right and left of the finger holes or between the sides in front and back of the finger holes.
(c) A ball drilled without a thumb hole may not have more than ¾ ounce difference between any two halves of the ball.
(d) A ball drilled without any finger holes or indentations may not have more than ¾ ounce difference between any two halves of the ball.
(e) A ball used without any hole or indentations may not have more than ¾ ounce difference between any two halves of the ball.

Note that the 1 oz. top limit for balls drilled without a thumbhole is the current specification. NOT 3 oz.!
I have emailed TBA and asked whether the new 3 oz. spec will included when the rule is updated. Hopefully it will be.
 
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