Finding The Spine On A Fishing Rod Blank

So What Is A Fishing Rod Spine?

Almost all rod blanks are produced by wrapping graphite and/or fiberglass around a steel mandrel. This process causes a slight deviation in the material which results in softer and stiffer sides to the rod blank, and is commonly referred to as the spine.

Think of a rod spine as if it were your backbone. You only want to bend in one direction, forward, and it is the same with a rod blank.

Every rod blank has a spine; some are just more defined than others.

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Guide Placement with Static Deflection

Instructions For Finding The Rod Spine.

(Video tutorials provided below)

Step 1 – Wrap masking tape around the middle of the rod blank. This is where you will mark which side of the rod blank the spine is on.

Step 2 – Support the rod near the top with an open palm so that the section of the rod blank is resting at roughly a 30-degree angle.

Step 3 – Using your other hand, apply downward pressure to the rod blank as you roll the blank along a smooth surface.

Step 4 – You will notice that the blank tends to “POP” into a pronounced curve, and is difficult to role the blank out of that curve.

Step 5 – Congratulations! You just found the spine of the rod!

Step 6 – Now, mark the outside of that curve on the tape with a pen. We will refer to that side as the spine (or spine side).

Step 7 – If you are building a multi-piece rod, repeat this process for all rod sections. Keep in mind the rod always wants to bend in that direction and has the most lifting power.

Step 8 – If you are building a spinning rod, your rod guides will be located on the inside of the curve 180° to the spine.

Step 9 – If you are building a casting rod, your guides will be located on the outside of the curve on the spine.