White43; Your on the right track...these graphite arbors are for under the reel seat and yes you ream them out to fit the rod blank. If they are too large of an outside diameter, then they are for a larger reel seat. Proper size should fit thru the reel seat without having to remove any material from the outer diameter. Please don't feel that you are going against the grain by building a spinning rod....we are all anglers here and you mentioned you are building it for a special purpose. I happen to build and repair many different types of rods each year and found that it is best to use as many bushings under the reel seat as possible. They are light weight, give proper support to the reel seat, leave no air voids and the graphite ones tend to transfer the sensitivity from the rod blank to your hand nicely. Many builders use masking tape to make spacer bushings and yes these are easier to work with. I prefer to use a roll of fibreglass drywall tape cut into 3/8" strips. The webbing of the drywall tape allows the epoxy to blend thru the tape to the rod blank providing a good adhesion. I wind the strips around the blank to make bushings, leaving approx 3/8" to 1/2" between each one. Usually 5 bushings spaced evenly will cover the length required for the reel seat. Using Rod Bond 2 part epoxy paste, I spread it over the bushings, filling in the webbed tape and the spaces as well. Don't be stingy with the epoxy. It is always better to mix too much rather than too little. Clean up the excess with rubbing alcohol. From my experience, this method has provided the best adhesion between rod blank and reel seat on all of my rods.

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