Man , thats beautiful footage. Flywheel and one moving in sync with the arm swing. But what the heck does that mean mechanically? We can see it , feel it like MJ says but what is it about those swings that we are so attracted to. Balance, grace , power etc etc . Yes but consider what Homer meant by Rhythm and how the pivot and the arms must move in sync to ensure Rhythm.


Homers concept of Rhythm requires the clubhead , clubshaft , hands , arms to moving as a unit , in line , with a constant RPM about its centre albeit with different surface speeds depending upon how far away they are from the centre. Break the left wrist and break the Rhythm .

But there is an important consideration to be made between the relative rates of rotation between the Pivot and the Primary Lever to ensure Rhythm. Rotation of the Primary Lever being #3 power accumulator , roll power.


As I read Homer and correct me if you guys think otherwise. He's saying essentially " get the turning rate of the pivot and #3 power accumulator mismatched and the left wrist will tend to break". Club face problems , directional difficulty due to the clubhead swinging ahead of the hands.

So lets say you get your pivot turning faster than your #3 is rolling through the shot. That would logically lead to a shot that goes to the right to my mind as the Primary Lever would be trailing , clubface open. Vice versa for a manipulated Primary Lever that rolls faster than the pivot is turning.

A further complication is that the relative effort needed to rotate the pivot vis a vis the #3 is different.

I have this sneaking suspicion that when good golfers hit a bad shot its a Rhythm problem , but born out of a mis matched Pivot and Primary Lever rate of rotation. Tension can do it . Over acceleration , quitting.

BTW our old buddy Ted Fort is a genius when it comes to coordinating out of sync pivots and primary levers. He's got some drills that may some day be common fare on practice tee's the world over. I highly recommend him for anyone whose interested in a lesson. Hitters or swingers.

Need to edit .

Earlier I described the Angle of Attack as being a straight line drawn between impact and separation reasoning that that was what the ball knew. Homers definition would have it , the angle , the straight line as drawn between impact and low point.

We need to adopt this definitionally to be consistent with his drawings in 2-C.

It also presents another interesting observation in regard to how the same thing , geometric line or clubhead path (ie arc, tangent , cord , circle etc) when viewed from a different perspective , point of view takes on a different name . So again , to understand Homer's geometry his words on the subject , you must understand the implied perspective to each of his terms. Words make it all sound too complicated again. Here are some drawings courtesy of Daryl and a post from Yoda.


Attachment 2953

Attachment 2952

The very same line when viewed from a looking straight at the golfer perspective , caddy view or from the players perspective is called two different names. Namely , the Angle of Attack and the Angle of Approach are the very same line, the very same cord on the circle .

Talking the "true" geometric (clubhead's ) Angle of Approach here , not to be confused with other similarly named concepts, procedures. I.e. this is the clubHEAD'S Angle of Approach as distinct from other components line of flight , path which may also have their own Angle of Approach . Right Arm, Right Elbow , #3 pressure point , Right Knee..... anything that moves forward during impact could have an angle of approach logically.

The true geometric Angle of Approach relates to the Delivery Line of the club head. The clubhead path . The circular orbit is the clubhead's (sweetspot's) orbit after all , nothing else.


The clubhead does not travel the straight line Angle of Approach or the Angle of Attack. It travels the circular orbit. Despite what you might have read , heard from various sources. It must be so and it is so. There are no "flat spots" to the circular clubhead orbit!!!!!

So, explain to me again, why these lines are important and not just, ho-hum, lines.

HB

I do not understand why HK didn't include Rhythm as the 4th Imperative. There are many good ball strikers who bob and/or sway, but none without Rhythm.

Because of the difference between the definition for IMPERATIVE and ESSENTIAL. Rhythm belongs in the ESSENTIALS "bracket" as does balance and stationary "head".

Essentials are a higher standard than imperative




HB

As per Yoda's post, the Angle of Attack (caddy view) describes Impacts Downwards direction. The Angle of Approach describes the Forward and OUTWARD direction to impact from the players perspective. Contrast this on plane, inside out impact (not stroke) to Steering. There is a big difference perceptually. And in terms of the direction of Thrust.... you actually do swing OUT for a square plane line !!! Even when the clubhead does not cross over the plane line!!!

They are JUST lines, In fact one line with 2 names that points down , out and forward on "the plane". the line goes from impact point to low point. but. The clubface is NEVER aligned to the line, the ball never travels on the line and it changes with ball placement and club length etc. So, Yes down out and forward is ok by itself. Just my perspective, but if someone uses the line for their swing that is ok, I guess.

How about using the #3pp? The rffw on the plane? That means the right elbow?



HB

Interesting point.

I suppose when you assume a flat left wrist, Rhythm is also assumed . Regardless , Rhythm and the co ordination of pivot turn and #3 roll are crucial.

Very succinct and interesting post Bear.


-Yes you are correct in a general sense but 2-J-3 B does describe such a procedure , albeit its somewhat of a rarity IMO. Namely the straight line Angle of Approach Delivery Line. . Delivery Line meaning clubhead line of flight as seen from the golfers perspective. A procedure where the clubhead while travelling the circular orbit appears to also cover the straght line Angle of Approach. Note the "appears". With an associated straight line clubhead blur, from the players perspective. Something the player could use to monitor his on plane motion , a visual companion to Tracing .

This straight line Delivery LIne (which will appeal to people who wish to to Steer) requires an unusually high plane angle, geometrically. One that planes the circular orbit to the players eyes. Only then will the geometric straight line Angle of Approach (the line drawn on the circle) and the club heads circular orbit (the delivery line) appear as one , to the golfer from his perspective, only. This is geometry more than golf here IMO. A geometric anomaly IMO. A manner in which you could Steer a straight line delivery line and still comply with the circular orbit . A concept you would not arrive at when looking at things from any other perspective than the players. Or for that matter from any other means of investigation other than geometry of the circle.

Put geometrically: "Under what conditions would a cord appear to lie on the same line as the circle?" Answer: When the circle is seen on edge to the point of view.


Getting to your point, (we've dealt with clubhead above) the clubface and the clubhead and the line of flight of the ball could theoretically be aligned to the Angle Of Approach. That'd be a straight push shot out to the right along the true geometric Angle of Approach assuming a ball played back of low point with its associated arbitrarily out to the right plane line. To hit a ball along a cord interior to this circle, along a target line left of the plane line, you'd need to Rotate the Grip square to your desired start line , the balls initial line of flight. Its a draw shot set up but mitigated by the extremely upright nature of the plane angle. This whole 2-J-3 B thing when complied with geometrically , IMO requires an usual sort of golf swing But it can be done.


-Yes the line changes with ball placement. Its runs from impact to low point. Which logically means that a ball placed at low point would have an Angle of Approach that did not point to the right . This relates to Homers use of the "arbitrarily" in 2-J-3 B , well IMO.





Im not saying that other similarly named "Angle of Approach" procedures , the right arms Angle of Approach, the Hitters cross line Thrust etc are invalid or anything , they aren't!!! But those procedures arent Delivery LIne club HEAD procedures specifically. The Right Arm's , the #3pp's , The Right Elbow's Angle of Approach is not the Clubhead's Angle of Approach. 2-J-3 B relates to Delivery LIne (club head) not Delivery Path (Hands)! These various procedures may be associated , related to the true geometric Angle of Approach the cord on the circle but they are not the same definitionally. Nor do they travel the same path towards impact. The hand is not the elbow is not the club head.

If you thrust straight line , cross line , down and out until both arms straight per 1-L? and employ a plane angle which is lower than your eye line you will see a curved clubhead (Delivery LIne) blur! You will see the Arc not the Angle's blur. Others may have said otherwise , but we are assuming the clubhead rides the circular orbit at all times as it is assumed in our model, as it must in real life. There are no flat spots ! Thrust is straight line the circular orbit is not, the delivery line as seen by the player is not, with this one exception.

If you play the ball at low point , by definition the Angle Of Approach will not point out to the right , but the direction of Thrust is still down and out all the way to both arms straight ( the club not crossing over into an inside out stroke).
Direction of Thrust is all important , it is related to but not one and the same as a Delivery LIne of the clubhead.

This is sticky business, Homers writing style didnt help matters.

Can't assume that!

Can you have poor Rhythm and a Flat Left Wrist? We must at odds with our definitions . Not uncommon.

There are 2 parts to HK's rhythm. The same RPM for BOTH lever assemblies- That is the flat wrist piece. The second is a steady/even (smooth) overtaking rate. I believe it is possible to have either, both or neither, and the second, overtaking rate, can have a "broad" range.

HB

But if you had a flat left wrist would not the entire Primary Lever club head, hands, arms be travelling at the same RPM about the Primary Lever's centre? Isnt that Rhythm , capital R by definition?

That is 1/2. The smooth overtaking rate (I said can be very broad) is the other half of rhythm.

Example-a smooth flippy swing may be good part 2, a hip or elbow stall making a "jerky" motion with flat left wrist is only part one.

Not articulate but done.

HB

As an aside.

Re the clubhead "overtaking" the hands with Rhythm (flat left wrist) assumed. IMO a key key concept for the guy on the tee. With a flat left wrist the entire left arm and club , (the Primary Lever) moves as one, rolls as one. The clubhead, the hands the left arm have the same RPM but different surface speeds given their distance from the centre of their motion, the left shoulder.

From the caddy view the clubhead passes the hands (somewhere around or after impact, depending). From the players point of view the clubhead passes the hands. But imagine a camera attached to the left shoulder which looks directly down the inline left arm and club and rolls with the Primary Lever as it rolls....... this camera would not see the clubhead as passing the hands!!!! If you played its video back you would see the whole world spinning around the inline Primary Lever .... inline Left Arm , Left Hand , shaft and clubhead. The world overtaking the intact Primary Lever if you will.


Break the left wrist and the clubhead does pass the hands , from any perspective. My grandfather used say " Well, it all depends where you're standing when your pictures took!".

It is important to know (for me) Is the camera a vertical camera for all hinges or is the camera attached to the hinge pin?
The results, to me, will be VERY different for each hinge action.

This Rhythm question may expand your circle geometry thread because it is part of the circle geometry but the "startionary "head"" [more
so] and Balance [less so] are also part of the geometry so I use caution.

HB

Camera attached to upper most part of left arm under the hinge so to speak.

Rather than interject my opinion I will ask a rhetorical question.

With a flat left hand we have the same RPM. For all hinges, but the "surface speed" or ratio of hand speed to clubhead speed is greatest for horixontal hinging, angled hinging is in the middle and the smallest retio for "true" vertical hinge. But if the ratio's are not the same how could it look the same from the center of rotation? It can't. So it won't?

Interesting, Hummm?

HB

The ratios for HH and AH are the same if the left wrist is level at impact and completely uncocked just past separation, in which case the hand and head speeds are not affected by Hinging type, because the full(HH) or half(AH) rolling wrist isn't speeding up the sweetspot through impact, but just rotating the shaft around it. The only thing HH & AH Hinging influences is face angle at separation. HH is more powerful only because it eliminates the layback component of AH through the impact interval, and so gives better compression, and not because the club head is faster.

No. Study 2-G

HB

IMO when Homer says "surface speed" he is not referring to the ratio of hand speed to clubhead speed. Surface speed in the context of Rhythm relates to for example a spoke on a wheel. Any point on the spoke will have the same RPM but the further you get away from the centre along the spoke the greater the surface speed. ie the clubhead given a flat left wrist will be travelling at the same RPM's about the centre as the hands but the clubhead will have a faster surface speed .

HInging will for sure have its effects on the surface speed of the clubhead given any #3 angle but the clubhead for vertical is still moving faster than the hands given a flat left wrist , Rhythm.

The KEY to understanding this lies in 2-G paragraphs 6 and 7- mainly 7. Note that the BASIC plane -For each of the hinges- is important to understanding this concept. RHYTHM and VERTICAL to the BASIC plane associated with the chosen hinge. That produces the "ratio".

HB

OK All Hinge Actions take on the characteristics of Angled when #3 is zeroed both in terms of Travel and Rhythm. So we have a term , Rhythm with several meanings, again.

BTW if anyone is following along .... a "Flat, Level and Vertical" Left Hand is Vertical to the selected Hinge Actions associated basic Plane .... Horizontal , Vertical or anything in between aka Angled.

This relates to setting up to a ball for shot shaping , in that when you put the ball back in your stance , your hands, more correctly your entire Primary Lever (left arm and club) must move back as well while maintaining the desired alignment to one of the basic planes. Its common for guys to keep their wrist watch, say ,pointing at the target as the ball moves back in the stance. This would only hold for Vertical Hinging!!!!

For instance, assuming Horizontal Hinging and Grip Rotation for a ball played back in the stance by a Manipulated Hands Swinger or a Hitter (almost everybody):

As you move the ball back in the stance, along the Arc of Approach , the Primary Lever must move back as well , while maintaining the left hands Vertical to the Horizontal Basic Plane Alignment. ie your wrist watch is pointing out to the rigth somewhat. Then without changing the hands alignment the handle is rotated in your loosened hands to square the clubface to the Target Line / Impact Plane Line. Draw shot tendency , but mitigated by Inclined Plane Angle since steeper planes take out some of the Divergence between face and clubhead path . OUT becomes DOWN in other words as Plane Angles Steepen. The axis of the balls rotation becomes less tilted. aka curve spin becomes back spin.

YES!!! Half or full roll of the LW cannot speed up the club head, unless you do it with a cocked LW. However, A. J. Bonar agrees with you. :thumright

Please provide TGM and HK Ref. to the points you are trying to make because what you are saying makes no sense without them.

HB

Grip a club with a level left wrist and extend it out in front. Now rotate the left wrist and see how much the club head moves. Make sense now? :think:

Now I see- BUT - Hinging doesn't work that way .

HB

Yes it does - Hinging is clubface motion in the Impact Interval.

I understand hinging. Please don't screw up those who are looking for good TGM info.

2-G would be a good start.

HB

Please don't screw them up by making them think that HH speeds up the club head. :nono:

It is obvious some do not understand the difference between absolute and relative- we are dealing with velocity here and the differences that are distinguished by their relative values. That is an impoprtant distinction for everyone.

HB

Maybe this is one of those "can't see the forest through the trees" kind of thing. The purpose of Hinging, Rhythm, etc. is, first and foremost, to satisfy the following point....

the Bold and color is my doing although one would think that HK would have done this himself given his desire to announce important basics.

This is sooo important. That the impact point be "carried" on trhe ball. Then the ball will be "carried" on the arc of the clubhead. Then the center of rotation will be the left shoulder ( except fo the uncocking left wrist). ???
BUT
the system rotation rate is only a "few" rev. Per/sec. The ball will have a "high" rev. per/sec rate. There must be a rotation but the introduction of rotation is how the ball is worked.

Baseball analogy- knuckle ball can be bad, fast ball with predictable rotation is good , curve ball(s) require high ADDED rotation.

[I should have said- not the center or rotation at the left shoulder but at the swings center of rotation, ]

HB

Here's an interesting video from Sean Foley. http://www.youtube.com/watch?v=ttxTnqVgkO8

We could draw how changes in plane angle require more or less plane line rotation for straight shots from a back of low point ball position using our model method .... Using the geometry of the circle type drawings.

PS looks like he's teaching a vertical drop to the elbow plane there!

Geometry of the Circle, shows that by making only one Alignment change, such as using a Steeper Plane Angle (Shorten the Grip), the Ball will start "Left" of Target (Steeper Angle of Approach). This needs a Compensation if one wants the Ball to Start on the Target Line. Open the Face by Rotating the Grip at Address.

Moving the Ball Aft of Low-Point on the same Plane Line (Flattening the Swing Plane), Although you have Closed the Clubface to compensate, the ball will curve. One needs to Steepen the Plane Angle if you moved the Ball Aft if you want the Ball to go Straight.

I imagine that a "Foley" student should have white tape on the grip of each club outlining the correct compensations for each club in the bag.