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Author Topic: Reference line  (Read 6317 times)

spinner031

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Reference line
« on: July 20, 2007, 09:39:40 AM »
I don't drill balls, but I'm curious to know how once I have found my PAP location (using a pin to PAP, MB to PAP system) on an undrilled ball, how do I know which direction on the ball to move to find my grip center.  How do I know, out of the infinite options on the sphere, which direction is north, east, south, and west, if you catch my drift.
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dR3w

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Re: Reference line
« Reply #1 on: July 20, 2007, 05:46:34 PM »
You don't.  You need another dimension such as the height above the grip midline, or pin buffer.
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Edited on 7/20/2007 5:46 PM

Edited on 7/20/2007 5:50 PM

Edited on 7/20/2007 5:50 PM
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spinner031

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Re: Reference line
« Reply #2 on: July 20, 2007, 07:31:10 PM »
*That doesn't make sense.  If I want a 4 1/2 x 4 layout for example, and I lay it out on the ball, the pin will just end up in a certain position.  If I also want to have a specific distance such as the pin 2 inches above the grip center, that will change my 4 1.2 x 4 layout, won't it?
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spinner031

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Re: Reference line
« Reply #3 on: July 20, 2007, 07:55:11 PM »
Like this:

In Brunsnick's video, how does he know which way is "down?"
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Raven829

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Re: Reference line
« Reply #4 on: July 20, 2007, 08:11:24 PM »
quote:
*That doesn't make sense.  If I want a 4 1/2 x 4 layout for example, and I lay it out on the ball, the pin will just end up in a certain position.  If I also want to have a specific distance such as the pin 2 inches above the grip center, that will change my 4 1.2 x 4 layout, won't it?


The pin can end up anywhere you want and still be 4.5 from PAP.  That's where the 3rd dimension comes into play such as pin height above midline, or pin distance from the VAL.  It is absolutely adjustable and isn't "locked" into a certain spot.  You can have a 4.5 x 4 layout and put the pin either 2" or 3" or other ranges above the midline.  

Don
--------------------
"On-base percentage is great if you can score runs and do something with that on-base percentage.  Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool
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spinner031

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Re: Reference line
« Reply #5 on: July 20, 2007, 08:25:20 PM »
I still don't understand it.  If you have the pin 4 1/2 inches from your PAP, and at the same time the mass bias is 4 inches from your PAP, that PAP is now static, it can't be moved, or else the distances ("4 1/2" and "4") will change.

Then you measure down, for your vertical measurement, and left, for your horizontal measurement.  Now you have found the grip center, which is static.  So the pin is now going to be in the location it ended up with, and if you want the pin a little bit higher than it ended up, you can't change it because it will throw off the other measurements.  What aren't I getting here?  I am really twisting my brain into a helix here.
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Raven829

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Re: Reference line
« Reply #6 on: July 20, 2007, 08:28:33 PM »
I'm taking some pics for you right now so you can see what we are talking about.  I understand your question but I'm not smart enough to verbalize the answer.  

Edit-
My camera is being a pain.  I'm trying to fix it.

Don
--------------------
"On-base percentage is great if you can score runs and do something with that on-base percentage.  Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool

Edited on 7/20/2007 8:36 PM
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Raven829

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Re: Reference line
« Reply #7 on: July 20, 2007, 08:58:46 PM »
Fugg it, the camera is not cooperating.  This is the best way I can explain it.  For simplicity we will assume a PAP of 5" over.  After you have your layout drawn (in your example a 4.5 x 4), you need a 3rd measurement, such as pin height above midline.  Let's say you want 2".  Take a compass and put the point on the pin and draw a 2" arc around the pin.  Now you take your quarter scale and draw a line from your PAP marking that is 5"(your PAP) and is also tangent to that arc you just drew around the pin.  This mark is your grip center.  

If you wanted the pin say 3.5" above, you instead would draw an arc 3.5" around the pin.  Put the quarter scale on your PAP mark (this hasn't changed from the first example) and draw a 5" line that is tangent to the arc around the pin.  This point is your grip center.  You still have a 4.5 x 4 layout.  

Don
--------------------
"On-base percentage is great if you can score runs and do something with that on-base percentage.  Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool
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strikealot

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Re: Reference line
« Reply #8 on: July 20, 2007, 09:11:00 PM »
http://brunsnick.com/how_to_layout_a_bowling_ball.html

you may have already seen this but here..

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strikealot

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Re: Reference line
« Reply #9 on: July 20, 2007, 09:21:05 PM »
your axis pt will not move by swing center of grip around by moving pin up or pin down..as long as your horizontal line measuring from your vert axis line is perpendicular to your VAL your axis pt will not move..



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Edited on 7/20/2007 9:21 PM
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spinner031

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Re: Reference line
« Reply #10 on: July 20, 2007, 09:38:16 PM »
So if I tell the driller in the proshop to drill my ball up 4 1/2 x 4, I also need to tell him how high I want the pin above the midline, right?  Won't my pin position change the ball reaction?  Why not start with the pin on the GC in the first place and go from there?  It seems to me that if you're going to go through the trouble of laying out a ball with the pin to PAP x MB to PAP layout and end up changing it, why go through all that trouble?

Edited on 7/20/2007 9:42 PM
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strikealot

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Re: Reference line
« Reply #11 on: July 20, 2007, 09:48:44 PM »
http://www.ebonite.com/products/detailnvs.php?PRKey=273
http://

they lay out balls here also to try to help you understand...
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current arsenal...to many to list...

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strikealot

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Re: Reference line
« Reply #12 on: July 20, 2007, 09:50:56 PM »
i dont believe pinup or down has as much effect on reaction as the actual distance from the pin and your PAP...
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jgreenwd

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Re: Reference line
« Reply #13 on: July 21, 2007, 01:16:16 AM »
Let's see if I can help you visualize this:

Assume our distance from pin-to-PAP and MB-to-PAP are equal at 4.75" and they form an 'L' (just to make it easy to visualize) on the ball. Drape a 5" string on the ball and hold one end fixed at the PAP. Now, no matter where you put the other end of the string, the Pin and MB are still 4.75" from PAP. Spin that string all the way around the ball and the P2P and MB distances are still 4.75". We used a 5" string just as an average PAP, with no up or down distance. The string itself then becomes the midline (not the case if you have a vertical component to your axis). This is why you really need a 3rd coordinate.

When you move the pin up or down from midline, you're manipulating the RG of the ball. The farther away from midline you go, the higher you raise the RG. This caps out at 6-3/4"; after that you're lowering the RG back down by moving closer to a negative pin, 180 degrees from the pin. This is where those RG min and max numbers from the manufacturer come into play.
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Raven829

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Re: Reference line
« Reply #14 on: July 21, 2007, 05:07:58 AM »
quote:
So if I tell the driller in the proshop to drill my ball up 4 1/2 x 4, I also need to tell him how high I want the pin above the midline, right?  Won't my pin position change the ball reaction?  Why not start with the pin on the GC in the first place and go from there?  It seems to me that if you're going to go through the trouble of laying out a ball with the pin to PAP x MB to PAP layout and end up changing it, why go through all that trouble?


Your pin position will only change in relation to high above the midline it is, not how far from your PAP it is.  In that regard, yes it will change the reaction by changing the RG.  jgreenwd put it quite nicely.  

Don
--------------------
"On-base percentage is great if you can score runs and do something with that on-base percentage.  Clogging up the bases isn't that great to me. The problem we have to address more than anything is the home run problem."
~Dusty Baker being a total fool
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