I'm extending a blank from 6'6" to 7' (6 inches). The butt dia. of the blank is .42 per my caliper. I have some alum tubing that is .500 O.D. but it is .395 I.D. Really close but, still, it won't slip over. Customer wants an exposed blank real seat which limits the butt grip to 8" long. (6" exten. + 2.5" oversleeve -.5" reel seat base to opening). I've looked at cuttin the butt of the blank and relocating everything up the blank so as to get into a smaller I.D. but this will make the handle about 3" longer which is not really an option. Does anyone know where I can find aluminum tubing that is about .437 I.D. and less than .750 O.D.? Better yet, any ideas on solving this problem:
User wants, exposed blank reel seat and originally said a 7" handle on St.Croix 3C66MM extended to 7' . Not gonna get a handle that short on a 7' blank and maintain balance, I think, but we'll try to get close and see.
I normally form cork butt grips on a 1/4" mandrel and then ream to fit. However, .750" is cutting my reaming a might close to the O.D. of the cork in some places creating a precarious situation. Should I try to form the cork on the aluminum tubing and then mount her up? If I do this, I can get a piece of tubing at Lowe's but it's gonna be .500 I.D. Then, what's the best method to make up that difference between blank and tubing (foam arbors, thread, etc.)?
Additionally, let me back up a bit. If I talk him outta the exposed blank reel seat, I could conceivably cut some of the butt off. If I do this, does it alter the dead lifting power of the rod or is it maintained/altered by virtue of the extension?

Why ot use graphite the same color as the blank then you can make the handle the way you want with wories

The aluminum will be a little heavy in that length on that type rod, I'd do what Steve suggested and use a scrap piece of graphite rod blank as an oversleeve. Build the handle on that and insert the blank into the fore end of the handle assembly. Most fishermen would never suspect it, but Daiwa and other commercial rod makers have built their rods in this same manner for well over a decade now.

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