I've got the book "Golf Club Design, Fitting, Alteration & Repair" by Ralph Maltby. 4th edition. This is a book of 896 pages and argueably the bible of clubmaking. Page 792-798 covers the topic "What happens when an average golfer hits a drive?"
There are a number of pretty interesting points in there that I think merits a post. These are not exaxt citations, but - to me - the essence of it.
CLUBHEAD TARGET LINE ACTION - DOWNSWING
Initially in the downswing the clubhead will resist the downward motion and lag the shaft. But since the clubhead is on the end of the shaft during the downward acceleration it will accelerare faster than any point on the shaft & actually catch up AND PASS the (my note: forward leaning) shaft just before impact. So the clubhead is leading the shaft just before impact.
Conclusion 1: Forward flex & loft reduction just before impact
CLUBHEAD ROTATION ACTION - DOWNSWING
The clubhead catching up & passing the shaft it will also cause the clubhead to close slightly (Since its principal mass is outside the plane). Maltby: Each 1" or shaft flexing (forward) will cause the clubface to close 2 degrees. (It will also cause to lie to flatten slightly).
Conclusion 2: Clubface should be open at address!
IMPACT
Collision of clubface and ball causes to shaft to flex backwards to that once again the clubhead is lagging the shaft.
Conclusion 3: None particular, but that's what we've all seen
IMPACT SENSATION
Malty explains that a golfer is NOT able to determine the feel at the moment of impact. Reason: By the time the impact has travelled through the clubhead, through the shaft, to the hands, into the brain and eventually being registered as a sensation the ball is already 10-12" from the clubface and in flight.
Conclusion 4: The golfer will think that the shaft is leaning forward at impact a lot more than it actually is!
Again: I think all these points strongly promote that:
- Clubhead should be slightly open at adress
- The golfer will sense (due to ball->brain time delay) that the shaft is less backward leaning than it actually is. I.e. he might think he is hitting up on it, since that is what his brain registers.
- Since (assuming a reasonable swing speed & flexing shaft) the clubhead passes the (forward leaning) shaft just before impact, the impact start with a less lofted clubface than what the golfer perceives.
In the book, Maltby has a sequence of picture taken with a high speed camera (of a "well known tour professional") that clearly shows:
In short the shaft and clubhead take turns in lagging and leading several times only during the downswing.
Now I am curious on your thoughts about this.
Tear it apart.
There are a number of pretty interesting points in there that I think merits a post. These are not exaxt citations, but - to me - the essence of it.
CLUBHEAD TARGET LINE ACTION - DOWNSWING
Initially in the downswing the clubhead will resist the downward motion and lag the shaft. But since the clubhead is on the end of the shaft during the downward acceleration it will accelerare faster than any point on the shaft & actually catch up AND PASS the (my note: forward leaning) shaft just before impact. So the clubhead is leading the shaft just before impact.
Conclusion 1: Forward flex & loft reduction just before impact
CLUBHEAD ROTATION ACTION - DOWNSWING
The clubhead catching up & passing the shaft it will also cause the clubhead to close slightly (Since its principal mass is outside the plane). Maltby: Each 1" or shaft flexing (forward) will cause the clubface to close 2 degrees. (It will also cause to lie to flatten slightly).
Conclusion 2: Clubface should be open at address!
IMPACT
Collision of clubface and ball causes to shaft to flex backwards to that once again the clubhead is lagging the shaft.
Conclusion 3: None particular, but that's what we've all seen
IMPACT SENSATION
Malty explains that a golfer is NOT able to determine the feel at the moment of impact. Reason: By the time the impact has travelled through the clubhead, through the shaft, to the hands, into the brain and eventually being registered as a sensation the ball is already 10-12" from the clubface and in flight.
Conclusion 4: The golfer will think that the shaft is leaning forward at impact a lot more than it actually is!
Again: I think all these points strongly promote that:
- Clubhead should be slightly open at adress
- The golfer will sense (due to ball->brain time delay) that the shaft is less backward leaning than it actually is. I.e. he might think he is hitting up on it, since that is what his brain registers.
- Since (assuming a reasonable swing speed & flexing shaft) the clubhead passes the (forward leaning) shaft just before impact, the impact start with a less lofted clubface than what the golfer perceives.
In the book, Maltby has a sequence of picture taken with a high speed camera (of a "well known tour professional") that clearly shows:
- Clubhead leading shaft just before impact
- Clubhead lagging shaft just after impact
- Clubhead catching up and passing shaft AGAIN just after impact
In short the shaft and clubhead take turns in lagging and leading several times only during the downswing.
Now I am curious on your thoughts about this.
Tear it apart.