Shaft Spine

The shaft spine is the stiffer structural seam that naturally forms during the manufacturing process of both steel and graphite shafts.

Because materials aren’t perfectly uniform, every shaft has at least one area that’s slightly firmer or less flexible than the rest. When the shaft bends during the swing, it tends to favor this stiffer section, which can influence how the clubface returns to the ball.

Fitters and builders identify the spine to understand how the shaft wants to rotate and load. While modern shafts are more consistent than older models, the spine can still play a role in fine-tuned builds. By locating and aligning the spine (or choosing an orientation that avoids it dominating the bend), builders help the shaft deflect more predictably. This supports better timing, tighter dispersion, and a more consistent feel across the set.