# shaft bending



## nil1121 (Jan 31, 2012)

When i have done slow motion video of my childrens swings, i have noticed that the shaft bends like a banana on the down swing and the middle part of the shaft is highest. I understand there are different kickpoints etc.

Is this correct, should the shaft be bending the opposite way with the head being lower than the middle of the shaft, it then catches back up at impact, surely shouldn't it be with the club head being behind the shaft and then catching up at impact making maximum speed at contact ?

any help appreciated.

thanks


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## USER1999 (Jan 31, 2012)

This is a peculiarity in the way video is recorded, and in no way represents what the golf club actually does.

You need to film at about 240 fps on a digital camera to get any true picture of what the shaft does.


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## BTatHome (Jan 31, 2012)

.... or a better camera


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## nil1121 (Jan 31, 2012)

this is taken with a 240 fps camera


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## SocketRocket (Jan 31, 2012)

The shaft bends back in the backswing but bows forward in the downswing.  The weight of the clubhead creates this action.  This photo shows it:


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## Region3 (Jan 31, 2012)

For anyone experiencing this, take a picture with the camera held upside down and see which way the shaft looks like it bends then.


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## JustOne (Jan 31, 2012)

SocketRocket said:



			The shaft bends back in the backswing but bows forward in the downswing. The weight of the clubhead creates this action. This photo shows it:
		
Click to expand...

Actually it can flex *both ways* according to how well you swing.

The club bends back. It's one of the reasons why you can have the toe up on a driver at address and yet the head will come in flat. Most pictures will show a forward bending (even the one you posted SocketRocket) as the frame rate/exposure just isn't fast enough to capture the shaft properly.

HOWEVER..... it IS possible for the shaft to flex forward.... if you take the load off of it before impact. The COG of a driver is behind the shaft so if you slow down the shaft the head keeps pushing a bit. It would be surprising (well it would to me) if you'd ever see more than 1" of forward flex as it'd have to come to a pretty abrupt stop! I personally doubt very much if it would even be that much but seeing as I don't own a 17,000fps camera it's just an assumption  

Even Swingvision isn't fast enough to capture it although I think they've got a camera called SuperG now? which might just show the facts.


From a club manufacturer...



			The effect of tangential acceleration can be either *positive* or *negative* on the shaft. If the head is still accelerating (gaining speed) just before impact, the shaft will *bend backwards* (shaft lag) thus reducing the loft and offsetting the effect of centrifugal acceleration which always wants to bend the shaft forward before impact. If the golfer *slows the club and losses tangential acceleration before impact the shaft will bend forward* (shaft lead) and increase the launch angle.
		
Click to expand...

I'd go as far as saying if you see any picture where the head is deflected forwards more than 1 or maybe 2 inches it's the CAMERA not the shaft.... mine flexes backwards!


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## JustOne (Jan 31, 2012)

Just as an aside... this is what happens to aircraft engine blades if your shutter speed isn't fast enough....!!

[video=youtube;LVwmtwZLG88]http://www.youtube.com/watch?v=LVwmtwZLG88[/video]

 


LOL


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## Foxholer (Jan 31, 2012)

From what I understand, it's a very simple explanation - and it's the (Digital) camera that causes it.

Your Digital Video scans each 'frame' from top-left to bottom right. So by the time it gets to your clubhead, it's moved slightly forward - giving the impression that it bends.

It's, sort of, the digital equivalent to the Doppler effect.


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