Post by: BrunsNick on October 25, 2006, 07:49:29 PM
www.brunsnick.com
Also check out FAQ section for other recently added articles!
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Nick Smith ... A.K.A. Les Badderâ„¢
Brunswick -=- PBA 03-06
http://www.BrunsNick.com
¡Viva la nación de Brunswick!
Edited on 10/26/2006 3:38 PM
Post by: Raven829 on October 26, 2006, 05:58:08 AM
Don
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"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
Post by: Raven829 on October 26, 2006, 06:15:12 AM
Don
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"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
Post by: directdrill on October 26, 2006, 06:28:28 AM
That was a great video. I do have one question. Why was the line drawn at an angle of 50 degrees?
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Hook 'em Horns!
Post by: Jeff Ussery on October 26, 2006, 11:19:44 AM
I don't mean to hate, but I feel that I need to point out a couple of observations with regards to this ball layout video. There is a conceptual/real problem in the method that you layout a bowling ball, and the people on this forum need to be aware of the differences in the outcome. Because I'm a geometry geek, and love talking about these things, this will get long. I apologize for that up front.
When talking about positive axis point in relation to the gripping holes on the ball, there is a universal method that pro shop operators use to locate that positive axis point. We first draw a centerline on the ball that splits the bridge and thumb hole in half. We then locate the grip center by measuring the span and dividing it in half (this process is up for a totally different discussion at another time). Measuring from either the fingers or thumb, we mark the grip center at one half of that span measurmement along the centerline. We then use the Pro Sect to draw a perpendicular line to the centerline at that mark. This line is called the grip midline. We extend this midline on the ball beyond the positive axis point that we have found using various methods (marking a thrown ball, using an armadillo, etc.). Finally, we draw a perpendicular line to the midline that intersects the positive axis point. This line is commonly referred to as the vertical axis line. We then note those positive axis point measurements as (blank) inches over x (blank) inches up or down.
I hope that everyone can agree on this so far. These are relatively simple concepts.
The problem with the layout video deals with the process of how you reversed your positive axis point measurements. In a situation where the bowler has a vertical coordinate measurement in their positive axis point (whether it's up or down), you must measure the vertical axis line measurement first, and then draw the perpendicular midline across the ball at the appropriate measurement. Finally, you draw your final perpendicular line at the appropriate distance to mark the centerline of your "grip to be." Your video showed you "reversing" the midline measurement first and then measuring a vertical measurement along the centerline of the grip. This process is not valid and does not result in the appropriate pin to axis measurements.
The problem with this method is that you are drawing perpendicular lines on the surface of a spherical object. If the bowling ball was flat, like a piece of paper, this method would be perfectly fine. But when you reverse the midline first, followed by the vertical measurement, you are changing the relationship of the pin to the bowler's positive axis point.
I tried a few examples here to give an example of what I'm talking about. All of these layouts were done with a 4 1/2" pin distance at a 50 degree layout, just like your video example.
I used your layout method with a 5 3/4" x 1/2" Up PAP. After using your method, I decided to layout the bowler's positive axis point using the process described above, which everyone uses in the pro shop world. When I draw the bowler's PAP using perpendicular lines on the bowling ball from the grip center found using your layout method, the PAP moves approximately 3/8" from the original location. Using a PAP of 5 3/4" x 1" Up results in a larger "miss" of 3/4".
I did two other examples using the 4 1/2" pin distance at a 50 degree angle. Using a 4 1/2" x 1/2" up PAP results in a "miss" of 1/4". Finally, using a PAP of 4 1/2" x 1" Up results in a larger "miss" of 1/2"
It's important to note that the size of the bowling ball does matter in this exercise. The Pro-Sect does not adjust for the size of the bowling ball, and the ball can range up to .095" difference in diameter. Pro shop operators and bowlers can try these examples that I've posed, but you may receive a slightly different measurement in the amount that the PAP moves.
Again, I hope people can see that the reason you must "reverse" the vertical measurement in a PAP first is because we are drawing lines on a spherical object. Also note that the longer your horizontal and vertical measurements measure, the larger the error would be in using this PAP reversing method. Your axis point measurements may be small enough to negate the error in most examples, but others will not.
In finishing, it's crucial to reverse the positive axis point in the appropriate manner so that you end up with the ball reaction you expected. In the example above of the bowler with a 5 3/4" x 1" Up PAP, I told you that the actual PAP moved by 3/4". In this example, the pin changed in relationship to the bowler's PAP by 3/4", and a 4 1/2" pin distance became 5 1/4". This would create a significant difference in ball reaction and may lead to undesirable results.
I hope that people understand this explanation, and if they have any questions about this process, I'll be glad to respond to them in this forum. Nick, I hope I didn't offend. I just want to educate people in these methods, and we need people to have the best understanding possible.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Edited on 10/26/2006 11:16 AM
Post by: Greg T on October 26, 2006, 12:15:02 PM
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Post by: Jeff Ussery on October 26, 2006, 12:29:11 PM
Do you understand conceptually what I'm talking about though? If you do not measure up/down the vertical axis line first and the reverse the midline, you will not end up with the desired pin position. And the longer the measurements of your midline and vertical axis line, the larger this error amount will be.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: BrunsNick on October 26, 2006, 12:46:28 PM
www.brunsnick.com/benoitclassic.wmv
When I wake up a little more and wipe out the sleep boogers in my eyes, I'll read your post. I don't function til I get a little Dr. Pepper in me.
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Nick Smith ... A.K.A. Les Badderâ„¢
Brunswick -=- PBA 03-06
http://www.BrunsNick.com
¡Viva la nación de Brunswick!
Post by: Jeff Ussery on October 26, 2006, 12:55:12 PM
This video works perfectly as the bowler has no vertical coordinate in their PAP. So their positive axis point measures 5" over x 0" (no vertical measurement). This is the ONLY scenario where reversing the midline of the grip first will hold the pin in the same relationship to the positive axis point.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: BrunsNick on October 26, 2006, 01:06:51 PM
Mapping a ball for video purposes really hasn't been done much, so there's bound to be a few hiccups.
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Nick Smith ... A.K.A. Les Badderâ„¢
Brunswick -=- PBA 03-06
http://www.BrunsNick.com
¡Viva la nación de Brunswick!
Post by: Jeff Ussery on October 26, 2006, 01:09:47 PM
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: Greg T on October 26, 2006, 01:12:07 PM
quote:
Sorry Greg, but I don't own a video camera at this time.
Do you understand conceptually what I'm talking about though? If you do not measure up/down the vertical axis line first and the reverse the midline, you will not end up with the desired pin position. And the longer the measurements of your midline and vertical axis line, the larger this error amount will be.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
I understand exactly what you're saying. But you know what they say, a picture is worth a thousand words. It would be excellent to see that in motion along with the explanation.
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Post by: BrunsNick on October 26, 2006, 01:14:02 PM
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Nick Smith ... A.K.A. Les Badderâ„¢
Brunswick -=- PBA 03-06
http://www.BrunsNick.com
¡Viva la nación de Brunswick!
Post by: Jeff Ussery on October 26, 2006, 01:19:50 PM
Choose a pin distance and a degree layout for a new ball. Draw the line from the pin to the mass bias locator as usual. Draw your angle line (50 degrees in Nick's example). Measure from the pin down that line for the pin to PAP distance that you selected.
From this point, try reversing your PAP as shown in the video. If your positive axis point is 5" over x 3/4" up, then draw a 5" line from that PAP mark across the ball, draw a perpendicular centerline, and measure 3/4" down to reflect the vertical measurement. If you've been laying balls out in this method, then you recognize this point as the bowler's grip center. Because the grip center is located in relation to the gripping holes, this point is true, and does not change.
But your PAP is measured from the grip center as I originally described in the first post. So now draw those same PAP measurements (5" over x 3/4" up in my example) on the bowling ball. You'll find that the PAP you've just drawn does not match the one that you were trying to originally achieve. This happens because you are drawing the lines on a spherical object.
In this example, you incorrecty reversed the midline first and then drew a perpendicular line to that called the centerline. The error occurs when you adjust for a vertical axis measurement along that centerline.
And I do want to clarify one point. I was actually in error earlier when I told Nick that a PAP with no vertical measurement was the only example where his video method would hold true. That is completely FALSE. Another scenario exists where the bowler's horizontal measurment in their PAP is 6 3/4". Because the centerline, midline, and vertical axis line are all perpendicular to each other in this new example, you could use the reversing method shown in the video. Other than those 2 scenarios, you will have an error margin in every example.
Told ya I'm a geometry geek. My best advice is to try this on your own with some balls. I believe you'll see very quickly the error that is caused by not reversing the vertical axis line measurement first.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Edited on 10/26/2006 1:15 PM
Edited on 10/26/2006 1:16 PM
Post by: Jeff Ussery on October 26, 2006, 01:31:50 PM
I haven't really adressed your post yet. You are dead on with the proper method to accomplish everything you're looking for. You do have to make sure that you are measuring the horizontal measruement along your tangent line from the point that is perpendicular to the midline and goes through the pin.
Your description leads me to believe that you know conceptually how to draw everything on the bowling ball. It's great to find people geometrically visioned people.
Geometry is cool!!!
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: Strapper_Squared on October 26, 2006, 01:48:01 PM
. I have always done layouts as Don... drawing an arc from the intended PAP to get the vertical component of your PAP measurement and drawing an arc from the pin to get the pin height relative to the center of grip. My problem is always deciding on how far above my center of grip I want the pin located... which really comes down to the conceptual layout of the ball and deciding what exactly I want the ball to do and how can I best achieve this...
S^2
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-Was Chris Berman trying to grow a moustache on MNF, or was that pine tar?
Post by: Jeff Ussery on October 26, 2006, 02:07:49 PM
I don't mean to discount pin height as a factor in your ball's reaction. It certainly plays a role. But, try not to relate pin height as a predominant factor in your bowling ball's ability to accomplish certain things. In my stuff, I use pin height as a minor adjustment in the length of my ball reaction.
You can check out more of my ball arsenal at www.proshoptraining.com. It includes pics, layout descriptions, and a general review of each ball I've drilled recently. I think you'll find some great info there.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: BrunsNick on October 26, 2006, 03:43:54 PM
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Nick Smith ... A.K.A. Les Badderâ„¢
Brunswick -=- PBA 03-06
http://www.BrunsNick.com
¡Viva la nación de Brunswick!
Post by: Strapper_Squared on October 26, 2006, 03:46:05 PM
I like the equipment section of your site. It just goes to show that ball drilling is still an "art" to some extent... sometimes its tough to get the desired reaction out of the lanes...
Thanks for posting and sharing knowledge.
S^2
quote:
Through my bowling experience, I would argue that pin to PAP relationship, preferred spin axis (sometimes indicated by a mass bias locator) to PAP relationship, and ball surface are far stronger influences on your bowling ball reaction.
I don't mean to discount pin height as a factor in your ball's reaction. It certainly plays a role. But, try not to relate pin height as a predominant factor in your bowling ball's ability to accomplish certain things. In my stuff, I use pin height as a minor adjustment in the length of my ball reaction.
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+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-Was Chris Berman trying to grow a moustache on MNF, or was that pine tar?
Post by: Jeff Ussery on October 26, 2006, 03:54:50 PM
I'm glad you saw what I was talking about. Geometry is the best!!
Anybody up for some pythagorean thoerem on a spherical object measuring 8.595" in diameter? Ah, never mind.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: BrunsNick on October 26, 2006, 04:00:01 PM
However, pin to pap could be assumed as an estimation, as pap could change (OMG END OF THE WORLD!!) lol, thanks for the help Jeff!
quote:
I made Nick's video!!! Sweeeeeeett!
I'm glad you saw what I was talking about. Geometry is the best!!
Anybody up for some pythagorean thoerem on a spherical object measuring 8.595" in diameter? Ah, never mind.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
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Nick Smith ... A.K.A. Les Badderâ„¢
Brunswick -=- PBA 03-06
http://www.BrunsNick.com
¡Viva la nación de Brunswick!
Post by: Jeff Ussery on October 26, 2006, 04:05:06 PM
Ah shucks, I just did. OMG, that's one of the really cool geometry lessons.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Edited on 10/26/2006 3:59 PM
Post by: BrunsNick on October 26, 2006, 04:06:03 PM
We can take 5 1/2 x 1 1/2 up and see the differences in the result of center of grip when we measure the right way, and the wrong way.
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Nick Smith ... A.K.A. Les Badderâ„¢
Brunswick -=- PBA 03-06
http://www.BrunsNick.com
¡Viva la nación de Brunswick!
Post by: Jeff Ussery on October 26, 2006, 04:38:07 PM
I can't believe I posted that comment about the scale and nobody immediately disputed me. Ha, maybe they already know about it.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: JohnP on October 26, 2006, 10:49:59 PM
quote:
I can't believe I posted that comment about the scale and nobody immediately disputed me. Ha, maybe they already know about it.
Nope, don't know about it, but would like an explanation in case I disagree!! -- JohnP
Post by: Jeff Ussery on October 27, 2006, 10:13:34 AM
The United States Bowling Congress defines certain static weight limits that our bowling balls must comply with. Those weights are:
For a ball weighing 10 pounds or more:
(a) Not more than three ounces difference between the top of ball (finger hole side)and the bottom (solid side opposite finger holes).
(b) Not more than one 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.
The weight limit in remark (a) is known as top weight. We refer to the other weights as side weight (positive or negative) and finger/thumb weight. This rule implies that we are weighing the difference between the two ball halves from 3 different positions.
The inherent problem with the Kaufman scale is that it does not weigh through the center of the bowling ball. The ball is held in the ring to the left side of the scale. There are two bearings that the scale pivots on, located just to the right of the bowling ball. The line that passes through these two bearings is in fact parallel to the line described in the static weight rule above (whether it be side, top/bottom, or finger/thumb). But because this line that passes through the pivot point does not pass through the center of the bowling ball, you are not getting a true representation of the difference between the two ball halves. You are weighing an object on the end of a pendulum with weights suspended at an appropriate distance in the opposite direction.
This difference or error margin increases as multiple densities and pieces of material are present inside the bowling ball. The scale is not able to adjust for different positions and manipulations of core design. It is pre-calibrated with a particular set of balls and is designed to perform within a certain range.
Now don't get me wrong. I'm not slamming the Kaufman Scale or anything. In fact, I think it's a great scale. It's obviously the industry standard, and pictures of it even appear in the equipment specifications manual. What I find to be comical is that we have a rule in our USBC rulebook that virtually none of us can follow, due to the lack of a properly designed scale. In fact, for decades your bowling balls have been weighed at the ABC/USBC tournament on a Kaufman Scale, as it is the accepted standard.
But it's important to realize that the Kaufman scale is not weighing EXACTLY what the rule book defines as our static weights. Without weighing exactly through the center of the ball, it is impossible to weigh the ball as definied in the rulebook.
I'm working on some qualitative data that I'll post for you later today. I've been testing balls on different scales for years, and this subject has come up several times in the design phase of other new products. Hopefully you can conceptually see how not weighing on a pivot point that travels through the center of the ball will not give you the EXACT results that you are trying to find.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: JohnP on October 27, 2006, 11:42:16 AM
Post by: Jeff Ussery on October 27, 2006, 11:57:50 AM
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: CoachJim on October 27, 2006, 04:57:48 PM
Post by: Jeff Ussery on October 27, 2006, 05:06:15 PM
I was actually the "conceptual" designer of that unit while at my last employer. But I'll admit that I don't fully understand the level of mathematics and construction that go into the device. The unit does weight through the center of the bowling ball, but it is an extremely sensitive unit.
They actually do still use Kaufman scales at the tournament. When I was at the tournament viewing the process, every ball that came up illegal was then checked on a Kaufman scale.
Of course, this brings up a whole different set of issues when your weighing between 2 different scales. We won't even delve into that here.
Hopefully everybody understands the physical concepts between trying to weigh a round object, one half versus the other, in a pivoting beam type scale.
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Jeff Ussery
Powerhouse Training Clinics
www.proshoptraining.com
Post by: Next Level PS on October 29, 2006, 08:06:45 PM
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"THE BOWLERS WILL NOT BE DENIED"
Post by: Traumatize on October 29, 2006, 08:13:53 PM
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Buffalo bowlers are the best all around in the country.
AMF Thruway Lanes Pro Shop employee, and I have no problem saying that I'm Officially a Ball Junkie.
Post by: Next Level PS on October 29, 2006, 08:18:11 PM
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"THE BOWLERS WILL NOT BE DENIED"
Post by: TheDude on October 30, 2006, 09:47:35 AM
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Timothy @Juniors Pro-Shop
Roto-Grip Star Proshop
Staff Writer 7-10 Split Magazine,EGO Communications
Montreal, Quebec.
Post by: duvallite on October 30, 2006, 06:46:43 PM