Dave A couple of things:
1. You were going off-line with Allan to discuss this issue about instances of shafts bending back prior to impact. I'd love to hear the results. Prior to reading about these things I would have assumed that the Hackman photo represented something that would be quite common. That is a heavy and later hitter with a soft shaft would be producing so much bend on the shaft that it doesn't have time to recover before impact. It was actually quite a surprise to me to see so much evidence for a bow forward prior to impact. I've been working with a strong hitter, late release, 10 handicapper and he wanted to try out a softer shaft. Result: low slice. Obviously similar things going on as in the Hackman photo. 2. I admit I'm confused by the Jones and Thompson graphs. Both show a drop in acceleration in the last 10 degrees. Also, Jones appears to be increasing in velocity right up to impact and Thompson's shows a slight decrease in velocity in the last 10 to 12 degrees? Doesn't this mean that the Jones graph should be showing an increase in acceleration? Perhaps I'm misreading this and would appreciate advice. The reason I'm surprised is that what we are saying is that the head is leading the shaft prior to impact. Doesn't this mean that the head is moving faster than the shaft at the finish? My layman's approach would have led to a guess that this would mean that the head is accelerating.? Cheers Graham ----- Original Message ----- From: Dave Tutelman <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, January 21, 2003 8:27 AM Subject: Re: ShopTalk: 20 min talk > Graham and Bernie, > I find that fascinating! Which pictures are those? I have Bernie's pictures > of Bobby Jones' swing, and all of them that show the clubhead approaching > the ball show it bent slightly forward. > > I have seen lots of pictures showing the shaft bent back once initial > impact has occurred; that isn't surprising at all, because the momentum > transfer has slowed down the clubhead. But I'd really like to see a picture > of a reasonably good swing with the shaft bent back just before impact. > > Bernie, could you please mail me the pictures that Graham has. Thanks. > > Cheers! > DaveT > > At 08:02 AM 1/21/03 +0800, Graham Little wrote: > >I've taken up Tom Wishon's suggestion about preparing a 20 minute talk > >about what happens when the club strikes the ball and I've been doing a > >bit of homework. Bernie sent me a series of photos that show the full > >swing including the point of contact. Thanks for the photos Bernie. One of > >the more interesting things about two of the photos is the fact that the > >shaft bends back at contact. We are used to seeing photos of the shaft > >bending forward slightly just before impact. However, these photos show > >that the shaft is not just straightened at the point of contact it is > >actually bent back. Will this have any affect on the ball flight or is it > >too late to matter? Do we have to rethink issues like the shaft flex > >taking this into account? > > > >Any comments? Does anyone have other photos of this sequence that may shed > >some light on this matter? > > > >Cheers > >Graham > > >
