I thought that roll was supposed to do kind of the same thing as bulge, as it pertains to "gear effect", but around a different axis. That being, shots hit low on the clubface would get more backspin, while shots high on the clubface would get less. Therefore, some roll was added so that shots off the bottom start lower, and climb higher, while shots off the top start higher, but climb lower.
If I read you correctly Tom, what you are saying is that I have drawn an erroneous conclusion (it sure wouldn't be the first time)? I suppose the shaft prevents the club head from pivoting around its own CG? I would have guessed that the flexibility of the shaft would have allowed some movement. Scott --- In [EMAIL PROTECTED], "Tom Wishon" <[EMAIL PROTECTED]> wrote: > David: > > About 6-7 yrs back when I started to move the roll radius to be a 4" .. > year for a Golf Digest project they had asked me to assist in. One of > the heads was a GBB2 all ti driver that I measured as a perfectly made > 9" roll radius. Two things hit me when I measured that head - one, that .. > > make it the same in golf? But truthfully, there is NO scientific > > performance related reason for roll to be on any woodhead. Hence one > of > > the reasons I moved in that direction to reduce roll starting some 6-7 > yrs > > ago and this year to start reducing it almost to 0.
