tallathlete
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James presented this video to all of us that attended the Trackan conferfence a few weeks ago. James did an exceptional job.....
YouTube - D Plane Model Video by James Leitz
YouTube - D Plane Model Video by James Leitz
James Leitz D Plane Video....
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peterjthomps
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Wow, fantastic video. Really solidified my understanding of the dplane, and should be required viewing for all PGA teaching pro's.
Something about that demonstration seems off to me. Seems like there has been a simplification that isn't right, maybe because of the single pendulum angled swinging they showed.
At 7:42 in the video, he shows the plane tilted to the left and says at contact the path is straight, and here he means the resultant path. To my thinking there has to be a clubhead path that is left, and then the downward hit provides the vectors to add more force to the right, but his model does not show a leftward path of the club, at least not to my eye. Seems to me he is showing a clubhead path, and calling it (in effect) a resultant path.
If the plane angle was 90 degrees or straight up and down, then there would be no horizontal affect of hitting down or hitting up. So I think the vertical angle of the plane combined with the angle of attack influences the resultant path, but his model does not show a leftwards clubhead path at impact, only a "false" resultant path.
If anyone can say why the clubhead path doesn't need to be left, please let me know.
At 7:42 in the video, he shows the plane tilted to the left and says at contact the path is straight, and here he means the resultant path. To my thinking there has to be a clubhead path that is left, and then the downward hit provides the vectors to add more force to the right, but his model does not show a leftward path of the club, at least not to my eye. Seems to me he is showing a clubhead path, and calling it (in effect) a resultant path.
If the plane angle was 90 degrees or straight up and down, then there would be no horizontal affect of hitting down or hitting up. So I think the vertical angle of the plane combined with the angle of attack influences the resultant path, but his model does not show a leftwards clubhead path at impact, only a "false" resultant path.
If anyone can say why the clubhead path doesn't need to be left, please let me know.
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Maybe that's my small bone of contention...the model shows the clubhead going straight at impact, and his narration also says the pointer tool is indicating path (is not a lie angle tool) which is also straight. But I guess I thought the actual instantaneousness clubhead path at impact was left, and the downward angle of attack on a tilted plane produced the additional rightward vectors to zero out the resultant path the ball feels. So in affect you couldn't demonstrate the resultant path.
Here is an example from Trackman's #7 newsletter, and I thought "swing direction" is the actual path of the club at impact, and the "club path" was what I'm calling the resultant path.
Here is an example from Trackman's #7 newsletter, and I thought "swing direction" is the actual path of the club at impact, and the "club path" was what I'm calling the resultant path.
Maybe that's my small bone of contention...the model shows the clubhead going straight at impact, and his narration also says the pointer tool is indicating path (is not a lie angle tool) which is also straight. But I guess I thought the actual instantaneousness clubhead path at impact was left, and the downward angle of attack on a tilted plane produced the additional rightward vectors to zero out the resultant path the ball feels. So in affect you couldn't demonstrate the resultant path.
Here is an example from Trackman's #7 newsletter, and I thought "swing direction" is the actual path of the club at impact, and the "club path" was what I'm calling the resultant path.
Why wouldn't the in to out path with the driver need to be 2.5*? Curious. It seems almost one to one with the driver and 1/2 with the irons.
tallathlete
New
Cwdlaw...the ratio changes because VSP changes with each club. A driver VSP is about 45* so the ratio is 1-1. Irons get more vertical, thus the 'down' doesn't produce as much 'out' with the higher VSP. Imagine this...a dead vertical VSP of 90*....like a ferris wheel. There will be zero 'out' regardless of down.
Brian Manzella
Administrator
The problem is that the downward vs. shaft lean is stuck on a 1-to-1 ratio at 45°—and darn near the secret is making it much less than that.
Good job by James.
I am working on making a video of my D-Plane talk I've given at conferences.
Good job by James.
I am working on making a video of my D-Plane talk I've given at conferences.
Something about that demonstration seems off to me. Seems like there has been a simplification that isn't right, maybe because of the single pendulum angled swinging they showed.
At 7:42 in the video, he shows the plane tilted to the left and says at contact the path is straight, and here he means the resultant path. To my thinking there has to be a clubhead path that is left, and then the downward hit provides the vectors to add more force to the right, but his model does not show a leftward path of the club, at least not to my eye. Seems to me he is showing a clubhead path, and calling it (in effect) a resultant path.
If the plane angle was 90 degrees or straight up and down, then there would be no horizontal affect of hitting down or hitting up. So I think the vertical angle of the plane combined with the angle of attack influences the resultant path, but his model does not show a leftwards clubhead path at impact, only a "false" resultant path.
If anyone can say why the clubhead path doesn't need to be left, please let me know.
The path and face are straight at the target to hit a straight shot. How can a path to the left and a face at the target hit a straight shot? Wouldn't that curve the ball to the right?
Path according to Trackman is the resultant path, so yes it would need to be straight at the target.
I'm not fully convinced, now, either way, but I will cogitate a bit on this. I have previously thought the downward hit on an inclined plane had rightward vectors that you counteract by having the gross overall clubhead motion be left at impact. Leitz's model says 'no.'
I'm not fully convinced, now, either way, but I will cogitate a bit on this. I have previously thought the downward hit on an inclined plane had rightward vectors that you counteract by having the gross overall clubhead motion be left at impact. Leitz's model says 'no.'
Brian Manzella
Administrator
The path is continually sweeping more leftward as you go down and then up the tilted plane.
But at the moment of impact, the path is directly at the target in order to go straight. If it all sounds confusing do this....seriously....it'll be more convincing than any words will ever be.
Get a piece of paper and a pen or short stick of some sort....
Tilt the paper like a plane board and put the pen on the paper and move it like a golf club on a Leitz's plane board.
Then put your eye.....seriously..... 1 inch from the tip of the pen(the clubhead) ......don't let anyone see you do this......and LOOK at the direction of the tip of the pen as it slides down the tilted sheet of paper towards "impact".
Get your eye right friggin' behind the tip of the pen and see for yourself how it's moving to the right of the base of the "plane"....the bottom edge of the sheet of paper as the tip moves down the plane.
Only at lowpoint is the tip moving at the same direction as the bottom edge of the paper (the HSP).
Notice how you have to shift the base of the paper to the left, if the tip of the pen is moving downwards towards the bottom edge. Line it up with your eye as close as you can to the tip of the pen and SEE what direction (horizontally) the tip is moving.
Words....terminology....and all that other BS won't convince you until you see it with your own eyes how something "continuously moves left" when it slides down and up a flat plane that "looks straight."
But at the moment of impact, the path is directly at the target in order to go straight. If it all sounds confusing do this....seriously....it'll be more convincing than any words will ever be.
Get a piece of paper and a pen or short stick of some sort....
Tilt the paper like a plane board and put the pen on the paper and move it like a golf club on a Leitz's plane board.
Then put your eye.....seriously..... 1 inch from the tip of the pen(the clubhead) ......don't let anyone see you do this......and LOOK at the direction of the tip of the pen as it slides down the tilted sheet of paper towards "impact".
Get your eye right friggin' behind the tip of the pen and see for yourself how it's moving to the right of the base of the "plane"....the bottom edge of the sheet of paper as the tip moves down the plane.
Only at lowpoint is the tip moving at the same direction as the bottom edge of the paper (the HSP).
Notice how you have to shift the base of the paper to the left, if the tip of the pen is moving downwards towards the bottom edge. Line it up with your eye as close as you can to the tip of the pen and SEE what direction (horizontally) the tip is moving.
Words....terminology....and all that other BS won't convince you until you see it with your own eyes how something "continuously moves left" when it slides down and up a flat plane that "looks straight."
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Yup. I guess the HSP is left. Maybe I complicated the impact vectors a bit too much. Still turning it over in my mind.
Thanks. I'm just about convinced. I've worked through dplane stuff a ton but thought that the force (as a vector) at impact was being applied in a direction "closer to" the Swing Direction. I guess my thought was that impact was occurring when the face was more at the second circle from the left in post 13.
Savy, do you know where this equation came from? I may want to tackle it a bit more in depth, since this has piqued my interest.
Club Path = Swing Direction - AoA[tan(90-SwingPlane)
You're getting it...it helps to think of impact as instantaneous. For a brief moment, the clubhead is moving at the target. But it is continually moving its direction "more left."
Anyway, regarding that equation, I came up with it one day. I actually was looking at some actual Trackman print-outs and made a few educated guesses and came up with it. Like if you plug in 90 for Swing Plane (like a Ferris wheel), the tangent function goes to zero and it doesn't matter what the AoA is, the Club Path = Swing Direction.
If you don't mind looking up numbers in the tangent tables, it can actually tell you a LOT about what's going on. If you're not into math or trig - I know it just looks like gibberish.
But if I can convince you of one thing, even if you don't "get it" right away, is that it's pretty simple. It may take a few days, or a few weeks to really sink in, but one day it'll just sink in and you'll own it.
But, personally, I am convinced that the final step is pure visualisation, and not words or terms or math. It's either a tilted Ferris wheel or a pen on a tilted piece of paper that makes it come clear.
Anyway, regarding that equation, I came up with it one day. I actually was looking at some actual Trackman print-outs and made a few educated guesses and came up with it. Like if you plug in 90 for Swing Plane (like a Ferris wheel), the tangent function goes to zero and it doesn't matter what the AoA is, the Club Path = Swing Direction.
If you don't mind looking up numbers in the tangent tables, it can actually tell you a LOT about what's going on. If you're not into math or trig - I know it just looks like gibberish.
But if I can convince you of one thing, even if you don't "get it" right away, is that it's pretty simple. It may take a few days, or a few weeks to really sink in, but one day it'll just sink in and you'll own it.
But, personally, I am convinced that the final step is pure visualisation, and not words or terms or math. It's either a tilted Ferris wheel or a pen on a tilted piece of paper that makes it come clear.
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