What is Spine and FLO?

Understanding Spine and FLO

As a certified professional clubfitter, I strive to build the highest quality equipment available. As part of that process, I Spine and FLO each shaft I install.

It is common for shafts to have a "spine" or an area of the shaft that most resists bending. It will also have a "natural bend point" or an area that has the least resistance. It is important to locate the natural bend point and the spine as the starting in the process of aligning the shaft.

Each shaft has a stable bending plane. That is the point where the shaft will stay on plane when in motion. To locate this, the club is clamped in a vice and the clubhead attached. With the assistance of a laser, the precise alignment is determined where the club stays on its 3 o'clock to 9 o'clock plane with no circular oscillation. That point is the Flat Line Oscillation or FLO.

The center of gravity of the clubhead can influence the FLO. I locate the stable bending plane with the clubhead installed to make sure it is aligned with the clubface once the club is completed. This ensures the shaft has been assembled for the optimum performance, accuracy, and consistency.