Thanks to OB and the others for responses. In the TrackMan world, the "equivalent" to a measurement of ball "compression" is what is known as "Smash Factor", which is initial ball speed divided by clubhead speed at impact. The lower the loft, the greater the potential for this number to be. So a driver can be as high as 1.5, and short irons dip below 1.4 as a "best case scenario". The Dynamic Loft is the vertical angle of the "normal" to the clubface, relative to the ground, during impact. But it is this loft relative to the vertical Attack Angle which is the loft that the ball "feels". This is known as the Spinloft. Regarding Homer's Clubface Lay-Back...if the clubface does lay or tilt backwards from impact to separation, relative to the clubhead arc, increasing the Spinloft, then, all else the same, the compression will be less than if the Spinloft had remained the same during the interval. This seems pretty straightforward, if I am interpreting Clubface Lay-Back correctly.
But 2-C-1, Swingers Hinging says, in essence, that for maximum compression, the clubface must rotate around the same center as the shaft during the interval. I am looking for clarification of this.
You are partially correct but you've missed some very valuable and important information.
Quote:
This is designated the “Ideal Application” because it produces perfect Vector alignments because the Angled Clubshaft and the Closing Clubface (the “Full Roll” of Horizontal Hinge Action – 7-10) are rotating around the same center and there is no glancing force except for backspin.
For clarification, the Shaft and Clubface rotate around the same center, meaning, the Hinge Pin. HK, the "Shaft" isn't rotating around it's longitudinal center, but rather that it is moving on-plane around the Hinge Pin. The Clubface is also rotating around the Hinge Pin and not around the Longitudinal Center of the shaft. So, the Clubface is not rotating "normal to the path" when using any of the 3 Hinge Actions.
For additional clarification, there is another way to look at Hinge Action compared to the "Normal to the Path" rotation of the Clubface. In "Normal to the Path" rotation, the Clubface stays aligned to the Clubhead Orbit. This causes a corresponding Clubshaft Rotation around the Longitudinal Center of Gravity of the Golfclub. Hinging changes that. For Horizontal Hinging, the Longitudinal COG and Shaft, at Impact, are vertical, one above the other, due to the Mandatory Flat Left Wrist. They Both Rotate, together around the Hinge Pin but maintain their Vertical relationship to the Horizontal Plane (the associated Plane). This is very different than the Shaft continuing to rotate around the COG of the Golfclub as it would in a "Normal to the Face/Path" which is "Swiveling through Impact". In Angled Hinging, we have the same geometry except that the Hinge Pin is angled and the Longitudinal Center of Gravity of the Golfclub and Shaft maintain their relationship to the Angled Plane (Associated Angled Plane).
Trackman identifies "Spin Loft". This is probably very good to identify whenever you don't use Hinging. When not using Hinging, the Ball will roll on the clubface. TGM has such cases, for example, the Lob Shot, etc. For anyone using Hinging, Clubface Loft is considered at separation. TGM states that Vertical Line of Flight is a resultant force, and is a line bisecting the Line of Compression and the Rebound Direction. The Rebound Direction is 90 degrees to the line of compression (Angle of Approach, Angle of Attack). When striking a golf ball, if you lose the line of compression before separation, then you introduce scattered force vectors and it will result in scattered rebound vectors which will result in scattered resultant Force Vectors. That would be a Mis-Hit, poor execution unless done intentionally, and that will change the Vertical Line of Flight, Loft.
TGM considers "Smash Factor". It is not the quality of compression but how much of the ball was compressed. See Below: Also note that each line receives maximum compression.
When considering Layback, the Clubface is Laying Back relative to the Hinge. This is different than the "Normal to the Path" clubface layback that Trackman calculates because the Clubface is also closing about the Hinge Pin. In Angled Hinging, Layback does not necessarily lose compression because the Impact and separation points remain the same, but it will compress less of the ball by about 1/10,000 of an inch. Rather, Layback tilts the balls spin Axis.
Hybrid Mode
