I would like to see the results of an accomplished TGM pro (Brian Gay) work through the hinges while on Trackman. This has to have been done already by pros for equipment fitting changes, etc. Would be interesting to get feedback about what the pro thought the hinge did and what Trackman says the result is.

Thats interesting, Max I'll have to try to get a copy, thanks. Did it talk about an impact interval then as opposed to it being instantaneous?

When you say "65% of the difference between the clubface angle and the path"........are you suggesting that was similar to TGM's at right angles to the leading edge? Leading edge to me implies left to right not up and down. And how would that compare to modern thinking in terms of left to right ? Isnt Trackmans 85% an up and down variance? Not sure, but Id be interested in knowing.

Yes, it does talk about an interval and how the club moves about 3/4 inch during that interval. Haven't finished yet but so far is very good.

As far as starting direction, it is 3 dimensional. You can't separate left and right from up and down. It is going to do both. IIRC the 85% number is a 2d representation of a 3d image.

Nice OB. Very interesting!
 

Considering the turf they played on, most of those golfers had to work the ball like crazy, even on the putting green.



YBGF

K, thought Id read somewhere that the 85% was more the launch angle than the "left and right" in my sad terminology. What is "IIRC"?

IIRC - "If I Remember Correctly"

If there is friction between the clubface and ball (and unless you put WD40 on your clubface, there will be), then the ball will start off in a horizontal direction between the horizontal vectors of the "normal" to the clubface and the direction that the clubhead is moving during collision (If they are the same, obviously there is no difference). This frictional element is also the reason that your 56* sand wedge will only launch in the neighborhood of 30*, vertically, which is a percentage of the vertical vector of the "normal" to the clubface and the vertical vector of the direction that the clubhead is moving (Angle of Attack). So the ball launches both vertically and horizontally to a % of the difference between the 2 vectors for each. 85%, favoring the clubface, is an average. The actual % varies with friction and has been identified by TrackMan to be 65-95%, again, always favoring the clubface.

It's all in "Search". I'm still trying to figure out exactly what is in TGM. But I do know that this stuff is not.

OB,
Here's something that may help. It's important that you understand that the clubface can point at the target at separation or maximum compression or where ever you think the greatest moment of impact would be - and the ball can leave the clubface at right angles - AND the ball won't fly at the target!! Because it's riding on the clubhead.

Think of another example - The train is moving down the tracks at 100MPH (clubhead) and you throw a ball off the train (clubface) at a right angle to the path of the train at 100MPH - you threw it at right angles to the track- did it fly at right angles to the track? NO, it flew at a 45 degree angle to the track even though it separated from the train at right angles to the track.

There's more there - if you're interested but this creates a condition where on the small picture Homer Kelley's statement that the ball leaves the clubface at practically right angles to the clubface - The ball in relation to the clubface at right angles is dead on! While the ball movement in relation to the target would be flying in a straight line right of the target. The affect of the 65% or 70% or 85% clubface orientation of the ball flight in relation to the target - would be determined by the Vector quantity of the clubhead i.e. the train, based on clubhead speed, efficieny of compression, etc. - Let's say you are going to run over Bucket with your car and you have a slanted snow plow on the front - the more force you can create with the car, and the more he sticks to the blade and rides along with the blade before bouncing off - the more effect the car vector will have on his flight into the ditch.

Does it leave the face at right angles - YES. Does the clubface influence the flight say 70% versus 30% for the clubhead - YES It's not either or. You just need to identify the context in which you are discussing the subject matter at hand.

I have not read In Search of in years. It is basic reading for anyone doing the GCA clubmakers course. A good read, lots of good stuff but plenty of missing bits too.

Launch angles never took into account how far forward hands vs clubface were, which explains a heap of the difference between a clubs vertical measurement and actual launch.

InSearch never even considered right arm thrust, so was purely swinging in theory.

Having started with InSof, and then being taught TGM, there were paradigms to overcome in my mind. TGM just blew it away, adding to and exchanging some bits.

Most studies just miss the 'glance or crush' impact-separation area. Time is relative but far from irrelevant.

In Gummers book, was it not TJ who Homer had his book ticked off by?

Good to see Clubface is now seen as of a much higher order than Path by most out there now.

Im fascinated by this stuff, thanks.