The blade length only relates to the rate of closure when you consider the horizontal (and rearward) cg location. In theory, the closer the cg is towards the hosel the faster the blade would close, but you sacrifice stability and overall playability. As far as the rearward location, the further back the cg the more it can influence closure. In both cases, it has a minor effect. We don’t consider our blade lengths long, but what they should be in any particular design to get the horizontal cg in the best place for that design to make it as stable, solid and playable as possible. We don’t feel our blade lengths influence a draw or fade bias, but make the design stable. It is very difficult to calculate the rate of closure difference in different horizontal cg irons. There are so many other factors that influence the rotation of the iron head more than the horizontal cg location, most of which are player related. Shaft flex, tip stiffness and torsional stiffness are also factors. More influential are grip, arm rotation, hand rotation, body rotation, etc. So, in short, longer horizontal cg’s make the head more stable through impact. Shorter horizontal cg’s can, to very minor degree in irons, increase the speed of rotation. In woods, especially drivers, the influence is greater because of the distance the cg can be moved, to the heel or the toe, and the percentage of weight that can be moved is a higher percentage of the total weight of the head.
Britt Lindsey
Very insightful as always Britt, thank you!
As always with design (and physics) there’s so much more than meets the eye.
Appreciate all that the team does to educate us amateur club tinkerers.