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Author Topic: Help on wieght hole placement  (Read 2502 times)

cooksey

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Help on wieght hole placement
« on: September 24, 2005, 10:45:03 AM »
Hello all I am in need of some help. I drilled up a Roto Grip epic and don't know where to put the hole to get the best reaction and get the ball legal. The specs on the ball after drilling are as follows.
Top weight before drilling- 3.58oz
Top weight after drilling- 1 3/8oz
Right side weight- 3/4oz
Finger weight 1 3/8oz
The pin was 2 to 3" I put the pin over the bridge which kicked the cg about 1 1/4" up and to the right of the center of the grip. The mb is just barely to the right of the thumb. Just need to find what location to put the weight hole to get the top and finger weight down to legal specs. Thanks for any help.

cooksey
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JohnP

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Re: Help on wieght hole placement
« Reply #1 on: September 24, 2005, 09:40:53 PM »
You're allowed 3 oz of top weight, so you're OK there.  If you like the reaction you're getting from the ball, just drill the finger holes deeper to get the finger weight legal.  Drill the same amount out of each of them, or more out of the RF, so you don't get the side weight out of spec.  --  JohnP

cooksey

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Re: Help on wieght hole placement
« Reply #2 on: September 24, 2005, 09:57:18 PM »
Hey thanks for the reply. I like the reaction I am getting right now but would like it to read a little sooner. What location and size weight hole could I use to get the finger wieght to within USBC specs and get it to read the lane a bit earlier?

Thanks, cooksey
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" Focus the next shot is critical"

AIM:johncooksey24
" Focus the next shot is critical"

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cooksey

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Re: Help on wieght hole placement
« Reply #3 on: September 24, 2005, 11:14:07 PM »
ttt before I crash. Thanks for any help.

cooksey
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" Focus the next shot is critical"

AIM:johncooksey24
" Focus the next shot is critical"

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cooksey

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Re: Help on wieght hole placement
« Reply #4 on: September 25, 2005, 10:31:41 AM »
ttt

cooksey
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" Focus the next shot is critical"

AIM:johncooksey24
" Focus the next shot is critical"

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JohnP

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Re: Help on wieght hole placement
« Reply #5 on: September 26, 2005, 10:33:01 AM »
Surface preparation will affect when the ball reads a lot more than a weight hole will.  I'm not sure what the Epic's surface is OOB, but try taking it down (coarser sandpaper or Scotchbrite) a step or two.  --  JohnP

JohnP

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Re: Help on wieght hole placement
« Reply #6 on: September 26, 2005, 03:16:23 PM »
Deadbait -- I disagree.  Several months ago, as a result of a debate on this forum regarding how drilling fingerholes deeper affected static weights, I drilled the RF hole on an old ball extremely deep (don't remember exactly how deep, but well over 2").  This decreased the finger weight, positive side weight, and top weight proportionally.  --  JohnP

stormed1

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Re: Help on wieght hole placement
« Reply #7 on: September 26, 2005, 11:55:02 PM »
Depending on how deep you go with the fingers it will affect finger and top weight. If you put a weight hole just above the fingers you can drop the finger weight that way or a weight hole above the midline angled towards the fingers will also drop the finger weight but also drop the side weight. i would go deeper in the fingers first myself to lower the finger weight. this would also make a smaller weight hole more likely if you still have too much
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JohnP

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Re: Help on wieght hole placement
« Reply #8 on: September 27, 2005, 11:05:50 AM »
Deadbait -- Try the experiment, then post your results.  --  JohnP

T-GOD

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Re: Help on wieght hole placement
« Reply #9 on: September 27, 2005, 05:38:06 PM »
cooksey, first find the ending CG. http://lane1bowling.com/tech/cg.html Start with the first line just to the right of the ring finger, instead of thru the label in step 1. Then follow the steps to find the ending CG.

Seeing as though you like the way the ball reacts, we're not going to change it's position, but we'll decrease the total weight in that location. This should get the ball to start sooner. Just drill a hole thru the X after finding the ending CG.

Weigh the ball up for top weight using X as your CG, just like you would in a brand new ball. However much top weight it reads, drill out half of it. If it reads 2 oz. top on the X, then drill out 1 oz. using a 25/32 bit 2 1/2" deep.

Before putting the balance hole in, check to see if it will flare over that spot. Do this by checking the oil rings to see if they cross where the hole will go. If not, drill your hole.

If the flare rings cross where the hole will go, check back with me and we'll make an adjustment to where the hole will be drilled. =:^D