Spine Finding Tool - Instructions

by Al Goldberg
(More from Al Golberg)

As you get deeper into rod building you begin to assemble a number of tools that result in a better rod when completed. Tools like a power-wrapping device, slow-turning finishing motor and a spine finding tool are just a few of these tools. Determining the spine of a blank is an important and essential step to maximize that performance of the finished rod. While many excellent rod builders can easily find the spine of a blank by hand, the spine finding tool makes it quite simple even to a novice builder. Several blank component suppliers sell different types of spine finding tools. However, for those of you on a tight budget or are handy with home-shop tools here are simple plans to make a spine finder.

Materials Required

Clear Seasoned Hardwood 24x3x3/4 inches. Do Not Use Pine.
Two 1.25-inch automotive ball bearings that are unsealed, degreased, cleaned and lightly oiled
6 two-inch wood screws
Elmer's Yellow Carpenter's Glue
Circular Hole saw bit to match the OD of the automotive ball bearings

Assembly Instructions

Cut hardwood into three sections, two pieces 6 inches long and one piece 12 inches long.
Drill three screw holes through the base of each of the short wood pieces to accommodate the two-inch wood screws.
Line up each of the shorter pieces with the 12-inch base so that the three screw holes lie along each end of the 12-inch base. Carefully mark each drill hole onto the edge of the 12-inch base.
Carefully drill three holes into the end of each side of the base
Take one of the automotive ball bearings and line it up on the end of the shorter wood piece.
Make sure that the top of the OD of the ball bearing is at least one inch in from the top.
Using the hole saw, carefully cut a hole in one of the shorter wood pieces to accommodate the O.D. of the ball bearing.
After cutting the first hole, line up the two pieces of wood, and using the first hole drilled as a guide, drill the second hole in the other short wood piece.
Both holes should be perfectly aligned.
The ball bearings are packed with grease from the manufacturer. The bearings need to be able to roll freely. Therefore, the bearings need to be degreased and re-oiled with light machine oil. First remove the bearing seals. Then soak the bearings in a degreasing agent to remove all the grease then use a compressed air gun to blow out the bearings.
After degreasing, cleaning and re-oiling the bearings, press fit each of the ball bearings into the saw holes.
Align each of the vertical pieces with the base and apply a thin coat of Wood Glue to the joint then screw both pieces to the base.
Let the assembly dry overnight before using it.

Instructions on How To Use the Tool

Mount the finished tool to a bench.
Insert the butt end of the blank through both ball bearings.
Wrap a piece of masking tape around just above the mid-point of the blank
Gently press down on the tip of the blank. The blank will begin to rotate and settle in.
Where it comes to rest is the spine, which will be on the top of the blank or the outside of the curve.
Using a magic marker, mark the spine on the piece of tape.

More from Al Golberg