You wrote-: "Jeff . . . Homer said that he felt lag pressure so strong that he felt like he could lift himself off the ground . . . BUT he also said that lag pressure is measured out in ounces not pounds. That a pound of lag pressure would be too much to sustain . . . hmmmmmmm . . . . not really sure how to reconcile that."
That's my problem understanding lag pressure and its affect on ball flight distance. Each club needs a different level of forward shaft lean at impact (more for short irons). Therefore, for a given amount of forward clubshaft lean and a given clubhead speed at impact, wouldn't the amount of lag pressure experienced at impact be the same for different swinger-golfers who do not drive load the shaft? How could there be variations in the degree of loss of clubhead forward speed due to impact? How could different golfers have different levels of a "heavy hit" (whatever that means)?
Jeff.
Homer liked a "stock" amount of lag pressure . .. for consistency reasons I think. Hitters typically feel the load more due to the nature of the loading.
I'm not sure that there's a correlation of shaft lean to lag pressure . . . plus you may feel more pressure with longer clubs simply because they are longer. Bottom line you want to have a lag pressure that you can SUSTAIN and the PROPER amount of shaft lean for the shot you have selected and hopefully programmed at fix.
HK wrote-: "Over-Acceleration is the menace that stalks all Lag and Drag. Here it allows the Hands to reach maximum speed before reaching Impact and so dissipates the Lag. So the length of the Stroke and the amount of Thrust should be adjusted and balanced to produce a "High Thrust-Low Speed" Impact - "heavy" rather than "quick". "
I don't really understand the concept of a "heavy hit" in a swinger's action.
Here is a link to a golfer performing a left arm swing.
This is presumably drag loading at its purest. Does he have a "heavy hit"? What would a swinger need to do in order to have a "heavy hit" if PA#2 releases passively/automatically according to the principle of the endless belt?
Jeff.
In reference to the heavy feeling through impact, Tom Tomasello said it was sensed by keeping an awareness of moderately light grip pressure. If your grip pressure was too firm, the clubhead felt lighter. If the pressure was light, the clubhead felt heavier. Another slant on the topic, which may or may not help.
Austin was talking about a one-iron he made where he brazed a tungsten rod to the back of the club-face at the sweet spot. By doing that he increased Ma from what's normally about 0.2 kg to something much more. Maybe it was 0.3 kg.... So then assuming he could swing a "heavy" one-iron (say 0.3 kg) just as fast as he could swing a "light" one-iron (0.2 kg) tt (remember he was big and quite a strong athlete)
Vb = Vo (.3/.346)(1 + e) or Vo => 0.86 * 1.83 Vo = 1.58 Vo
1.58/1.48 = 7.2%
The ball would leave the club-face of Mike's modified one-iron having 7.2% more speed (provided he could swing the club just as fast). You see there is the catch. The heavier the club the more inertia it has. The more inertia it has the more force (and torque) is required to accelerate it. Over the years golfers have arrived at the optimal compromise for a given body type... we call that that "swing weight".
Its safe to say few people would be able to make Mike Austin's modified one-iron perform. Perhaps Sean Fister or Jason Zubak could...
Last edited by no_mind_golfer : 12-09-2008 at 11:45 AM.
Reason: still trying to make images show
You're welcome... I'll do a write up with the equations of motion (showing effect of spring stiffness as a variable on the collision response) eventually. I'm learning a new language (java) to make interactive web applets to simulate these effects as I type.
Could variations in the degree of downplane right shoulder thrust affect the amount of clubhead speed loss during impact due to ball collision, and the amount of energy imparted to the ball for a given clubhead speed and a given amount of forward shaft lean?
Consider a swinger's action. The release sequence is 4:2:3. The club reaches impact due to the passive release of PA#2 which is a CF-induced action. The right hand must keep up to maintain clubhead lag through impact. The right arm straightens passively in the downswing, but there must be enough right triceps muscle contraction to allow the right arm to straighten enough to allow the right hand to keep up with the left hand and maintain a bent right wrist/FLW through impact. However, straightening the right arm may not be enough if the right shoulder socket doesn't move forward enough downplane to support the right arm - so that one doesn't run-out-of-right arm. The more the right shoulder moves downplane, the more bent the right arm can be at impact. I am thinking of Hogan who had a very assertive pivot rotational action that allowed him to drive his hands inside very quickly post-impact, and that is presumably due to an actively driving right shoulder downplane. Could that driving right shoulder add thrust power (drive loading power) to the right hand at impact (passively via the bones of the right arm/forearm/hand) and thereby increase swing power at impact - even if one is a swinger?
Could variations in the degree of downplane right shoulder thrust affect the amount of clubhead speed loss during impact due to ball collision, and the amount of energy imparted to the ball for a given clubhead speed and a given amount of forward shaft lean?
Consider a swinger's action. The release sequence is 4:2:3. The club reaches impact due to the passive release of PA#2 which is a CF-induced action. The right hand must keep up to maintain clubhead lag through impact. The right arm straightens passively in the downswing, but there must be enough right triceps muscle contraction to allow the right arm to straighten enough to allow the right hand to keep up with the left hand and maintain a bent right wrist/FLW through impact. However, straightening the right arm may not be enough if the right shoulder socket doesn't move forward enough downplane to support the right arm - so that one doesn't run-out-of-right arm. The more the right shoulder moves downplane, the more bent the right arm can be at impact. I am thinking of Hogan who had a very assertive pivot rotational action that allowed him to drive his hands inside very quickly post-impact, and that is presumably due to an actively driving right shoulder downplane. Could that driving right shoulder add thrust power (drive loading power) to the right hand at impact (passively via the bones of the right arm/forearm/hand) and thereby increase swing power at impact - even if one is a swinger?
Jeff.
No... The collision takes place so fast, and the equipment is so flexible, there is nothing a golfer can do to change what is, what will be. On another forum I refer to this fact of life as:
Getting it done before hand .... because once ball and club head meet...
Jeff, I think that you got to let this one die... the science guys seem pretty strong on this one...and any way it does not matter. Lag and alignments are better places to spend your time IMO.
I never felt strongly about this issue. I always thought that ball flight distance was related to clubhead speed, and not to the pressure exerted on the shaft at impact in swingers where PA#2 is released passively. I am a little surprised that it also applies to hitters who drive load the clubshaft. Do you therefore believe that in a hitter's drive loading action, that the only factor is clubhead speed at impact and that push-pressure behind the clubshaft has no additive effect?
nmgolfer
I presume that the clubhead must have a finite amount of weight so that the clubface doesn't deform at impact. Presuming that the clubface is sufficiently rigid, you are presumably stating that additional clubhead weight and/or additional push-pressure thrust exerted by the golfer has no effect on ball flight distance (other than its effect on clubhead speed at impact). Is that correct?
What about the possibility of clubhead acceleration through impact due to drive loading in a hitter's action. In your mathematical model, you are presuming that clubhead speed remains constant for the entire duration of ball-clubface contact in both situations. However, wouldn't increased drive loading (thrust force = push-force) allow the clubhead to continue to accelerate while it remains in contact with the ball for a duration of 1/4000 second? A hitter is not simply applying increased mass behind his drive loading action - he is also thrusting and accelerating the club through the impact zone.
Jeff.
Last edited by Jeff : 12-10-2008 at 12:00 PM.
Reason: add more questions
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