#SPINE ALIGN NEW GOLF SHAFTS DRIVER#

Simply put, bending of the golf shaft occurs at every stage of a golf swing – from takeaway, to backswing, then transition, into downswing, at impact, and follow-through. After reading everything prior to this, I hope you are now questioning why the golf shaft spine matters. This difference in tip response from the two finite element models is easy to visualize with the above plot.

#SPINE ALIGN NEW GOLF SHAFTS DRIVER#

This simple setup mimics the manual spining process of my driver shaft. I applied a fixed restraint to the grip end of the shaft and a time-based force on the tip-end of the shaft (Figure 2). With my CAD model complete, in SOLIDWORKS Simulation Premium, I set up a Linear Dynamic, Modal Time History study. Since the CAD model is perfect, I intentionally added variations, or slight thickness imperfections on the inside diameter, to the golf shaft model to illustrate shaft spine. I re-created my golf shaft using SOLIDWORKS CAD, published dimensions for the raw stock shaft, but cut to the playing length I use of 46 inches. For shaft (C), this would require the orientation of the load to be applied somewhere between the horizontal, Fh, and off-angle, Fθ, loading shown in the Figure 1. For shaft (C), the bending will only be consistent and have zero twist if the load is applied along an axis passing through the centroid of the shaft aligned with the least moment of inertia of the shaft. For shaft (B), the bending will not be consistent from one load orientation to another, with the shaft tending to twist under the applied vertical and off-angle loading. Version (C) is a concentric circular cross-section with a small, localized thickness variation causing slightly different material properties, E’, at this thickened region.įor shaft (A), the bending will be consistent regardless of the load orientation – horizontal, vertical, or at some angle – with respect to the center of the shaft. Version (B) is a perfectly concentric shaft cross-section with different material properties, E1 and E2, on the left and right side of the vertical centerline. Version (A) is a perfectly concentric, uniform shaft cross-section with constant material properties. If I took a cross-section of the golf shaft it would look like an annular ring. Consider the three examples shown in Figure 1.

The mechanics of what is happening is explained by Beam Theory. Let’s look at what this means and work through an example using SOLIDWORKS Simulation. In Engineering terms, we are looking at the bending properties of the golf shaft. In golf terms, this is the shaft having a “spine”. These slight variations lead to golf shafts tending to flex better, with less twist, along some load orientations than others. Our designs must account for variations in component size, material, processing conditions, assembly procedures, and many other small influences that affect the finished goods. The reality of all manufacturing processes is they are never perfect. Even better, I can use SOLIDWORKS Simulation Premium to explain what it is and how it works. I am going to make my driver shaft use its spine. Here is a recent edge that I hope shows on-course gains by using technology. It also does not stop me from trying to find an edge, a little performance boost, with off-the-course work. To golfers, it is par for the course! These days I do not get to play as much golf as I would like, but that does not stop me from planning my next round. To non-golfers, this is often viewed as a form of psychosis. I have played in temperatures hovering near 110 Fahrenheit in the shade, when it was snowing, in tornado warnings, and in monsoons. All things considered I would rather be playing golf.

Spine align new golf shafts