Find what Dual Angle Drill you have

[bowl1820]

This is part 1 of 2 of a Dual Angle Drill series. Part 1 will show you how to find what Dual Angle Drill you have in your existing equipment.



Additional info from menorevs comments-
bwilll6413: this is wrong, every drilled ball has a mass bias. there for the angles are wrong.

menorevs: Not necessarily wrong. Its true that every drilled ball has a MB as weak as it may be. But because we can not predict where the MB will be after drilling (most time in thumb), only guess where the MB will be. That is why we use the 6 3/4 from pin thru CG.

Symmetrical balls are messy creatures when it comes to laying out DA drills. but you are wrong about one thing. The angle(s) do not change. The Drill angle changes. The VAL angle stays the same, and so does the pin from PAP.

menorevs: Also the only way you can accurately tell where the MB is located in any symmetrical drilled ball, or weak MB ball, is to spin it on a DeTerminator.


Any questions about this video should be directed to MeNoRevs. He can be found on bowlingchat.net MeNoRevs


FYI:
When you layout a undrilled Symmetrical core ball you start by drawing a line from the Pin through the CG and mark the spot at 6 3/4".
You use this spot as the PSA (MB) on the undrilled ball.

[noeymc]

great video but can u explain to me a little what the duel angel really means like am i able to get 2 different looks or is more less a way to kinda give u a idea when the ball will react thanks

[bowl1820]

See if this helps:
This was posted in Pro Shop Tips on September 27, 2013 by Luke Rosdahl.

This is the Dual_Angle_Lite, so I will attempt to keep it as simple as possible without getting into the heavy details. There are 3 numbers to the Dual Angle, initial or drilling angle, pin to PAP (positive axis point) length, and the angle to the VAL (vertical axis line). If somebody says “50x4x35,” 50 is the drilling angle, 4 means 4 inches from the pin to the PAP on the drilling angle line, and 35 is the VAL angle, which is measured from the PAP.

So what do those numbers mean?

Drill Angle
Recommended to stay between 10 and 90, the drilling angle controls the skid or length of the ball. The bigger the number, the more the ball is going to skid or the longer it’s going to get down the lane before it starts hooking.

Pin to PAP
The pin to pap distance relates to flare, and has a small effect on total hook as a byproduct. Flare is used to describe the distance between each successive oil ring on the ball, or how far they are apart. The more space between the rings, the faster the ball is changing its core orientation or rotation, meaning it is revving faster and as a result, hooking more. Flare is considered to be at maximum at a length of 3 3/8”.

If the number is smaller, on both a symmetrical and asymmetrical ball it will be a lower amount of flare, but still an earlier reaction. Past 3 3/8”, flare begins to reduce for a symmetrical ball, but will still remain high for an asymmetrical, though the larger the number gets, the more forward roll the ball will have, or the more it will have a “hook/set” type reaction rather than a continuous roll, to a maximum of 6 3/4”.

VAL Angle
The last number is the VAL angle, which instead of being measured from the pin like the drilling angle is, it’s measured from the PAP. This angle is recommended to be between 20 and 70 and it determines how fast the ball transitions through the phases of ball motion. The smaller the number, the quicker it will rev up and transition at the backend, while the larger the number, the slower the revving and slower the transition.

[dnhoffman]

Gizmo has made some good videos lately!

[Mike White]

Both of these videos perpetuate inaccurate information when using symmetrical cores.

On a symmetrical core ball, the drill angle does not pass through the CG unless by chance.

Since the PSA is undetermined on an undrilled symmetrical core ball, the thumb hole is considered to be the resultant PSA.

The PSA can be further modified with a balance hole.

To know what layout the bell ended up with, you need a determinator.

[bowl1820]

Just a FYI for everyone: Menorevs who made this video , Did address the issue that Mike points out above (yes he should have included it in the video). You had to read it in youtube comments.

Here it is for you:
bwilll6413: this is wrong, every drilled ball has a mass bias. there for the angles are wrong.

menorevs: Not necessarily wrong. Its true that every drilled ball has a MB as weak as it may be. But because we can not predict where the MB will be after drilling (most time in thumb), only guess where the MB will be. That is why we use the 6 3/4 from pin thru CG.

Symmetrical balls are messy creatures when it comes to laying out DA drills. but you are wrong about one thing. The angle(s) do not change. The Drill angle changes. The VAL angle stays the same, and so does the pin from PAP.

menorevs: Also the only way you can accurately tell where the MB is located in any symmetrical drilled ball, or weak MB ball, is to spin it on a DeTerminator.

Any questions about this video should be directed to MeNoRevs. He can be found on bowlingchat.net MeNoRevs


FYI:
For a undrilled ball with a symmetrical core, the drilling angle measures the angle between a line drawn from the pin through the center of gravity (cg) and the line drawn from the pin through the PAP.

[Mike White]

Just a FYI for everyone: Menorevs who made this video , Did address the issue that Mike points out above (yes he should have included it in the video). You had to read it in youtube comments.


Symmetrical balls are messy creatures when it comes to laying out DA drills. but you are wrong about one thing. The angle(s) do not change. The Drill angle changes. The VAL angle stays the same, and so does the pin from PAP.

Based on the comment, it appears he accepts the fact that the PSA does not remain directly in line with the CG after drilling (unless by chance).
However once you acknowledge that the PSA can/will move, you also have to accept that the true Pin location can/will move.
Usually the True Pin location (post drilling) is considered 6 3/4" from the new PSA on a line passing through the original Pin location.
I'm not 100% sure that is always the correct new location, but it appears to be the accepted standard.
Once the True Pin has changed, all of the resultant Dual Angle values could be different from the original intended values.

[menorevs]

Mike, I am glad you brought this up about the pin moving when drilling.

First we need to go over what the pin is. The pin is the Low RG of the ball, the MB, PSA or whatever you want to call it, is the High RG.


With Symmetrical, I dont even like to Dual angle anymore. Because the "Drilled MB" is affected significally by the type of holes you use for the thumb and weight hole. This is why "I" personally use the simple symmetrical drillings when laying out symmetrical bowling balls.

Spinning many, many balls after drilling, I have not seen a pin move more than a half of inch after drilling. It moves, but not enough to alter the desired ball reaction when laying out a ball. This has been an ongoing discussion with Mo and on various boards.

Remember, we are not sending this ball into outer space. Don't over think when laying stuff out, especially symmetrical stuff. That has been a hard lesson for me to learn since I am number driven. There is still a lot of ART that goes into this.

Based on the comment, it appears he accepts the fact that the PSA does not remain directly in line with the CG after drilling (unless by chance).
However once you acknowledge that the PSA can/will move, you also have to accept that the true Pin location can/will move.
Usually the True Pin location (post drilling) is considered 6 3/4" from the new PSA on a line passing through the original Pin location.
I'm not 100% sure that is always the correct new location, but it appears to be the accepted standard.
Once the True Pin has changed, all of the resultant Dual Angle values could be different from the original intended values.