Before anyone jumps to conclusions about an absolute method or solution to this repeatedly debated question, please read further. I have read countless forum posts here and on other forums about the same old question of rod butt extension. I have read Tom K’s article on extensions half a dozen times. I understand that an over sleeve is vastly superior to an inner sleeve extension. Everyone has their means and methods but I’m looking for some input into this particular problem.

I’ve even performed some inner and outersleeve extensions to great success. With that out of the way, I’ve got a free 1pc blank that I’m wishing to convert to a fly rod. It’s a sweet 7’0” ultra light graphite with mod-fast action. Small butt diameter, seems like a perfect mess around blank to try and get a cool little fly rod out of. If it doesn’t work it’s a scrap blank anyways. Think it’s gonna fall somewhere around a 6wt + or -. In an ideal world it could be a great little mangrove punching rod with a short heavy tapered fly line.

Here’s the thing, I’ve built out a few spinning blanks into fly rods in the past. All turned out to be cool rods but one thing made them feel off in everyone’s hands that casted them. The butt diameter of these blanks were always much thicker than that of corresponding fly rod blanks, quite understandably. All were fast or extra fast casting blanks, and short compared to fly rods, as they should be. It made the fly rod “swing” oddly and people couldn’t quite get past it. This blank is right at the same butt diameter as most 6-8wt fly rods so good there.

I’d like to get this blank to 7’11”, tip to end of fighting butt. Thankfully all of my fly rod grip assemblies with fighting butt and seat come in right at 11”. I’ve heard many mention maximum length you really can afford on an extension is 12”. So pushing the limits. If I could build out this handle onto a thicker piece scrap blank and perform an over sleeve I would, however by the time you get enough overlap on the blank it’s obviously going to look dopey and just wouldn’t work. However, it would be possible to build out handle assembly on thinner piece and insert into the butt. If I were to go this route, how much blank would need to be inserted to provide the right amount of stress distribution as to not get a break? I was thinking at least 8” but probably more. Would be epoxied into the main blank. So possibly a 20” total extension or so. I get that it would add extra weight but that’s fine by me. Only major concern is blank wall thickness but don’t have blank in hand yet to really see.

Some people say why go through the trouble of converting a casting blank to fly blank. They’ll say “just buy a blank that was designed for this purpose”. Couple points on that:
- One, high quality 1pc fly blanks in the correct length, action, and size are basically none existent. Some of the greatest fly rods I’ve ever used were unconventional lengths, tapers, and many outstanding 1pc blanks that seemingly can’t be replicated by custom rod builders. Sage Bass series (7’11” very powerful for quick shots and big flies) and Scott Sector 8’4” model, to name a few off the top of my head. 1pc blanks are outstanding because where I fish on the coast these rods never get taken apart. Ferrules loosen and slide and add weight though only marginally. The only rods I’ve broken in the past decade were on ferruled multi piece rods, clients won’t check them and they’ll loosen and hook a fish only to break the ferrule under load. They definitely aren’t the perfect net positive tool some make them out to be, depending on the situation.
- Two, it’s fun playing with blanks and seeing how they turn out. I dig unique tadpole type builds.
- Three, I’ve learned more about fly rods and spinning rods after experimenting with blanks in this manner.

Any suggestions or points would be greatly appreciated.

I believe your overlap quwation has been answered before in Tom's article and other posts also, the consensus is 6 times the diameter of your parent blank's butt.

Try to use a piece of blank that has a slightly thicker wall than the parent blank.
That should make it "stiffer" at that point.
If softer, you may get a "hinge" feeling in the handle area.
And for sure, that it is a graphite scrap.
And always, wrap over the area where you inserted the extension to reinforce it.

Best wishes,
Ron Schneider
Schneider's Rod Shop
Mountain Home, Arkansas
[www.schneidersrods.com]
mtnron40@yahoo.com
870-424-3381

Not quite sure the butt diameter is your issue, my Lamiglas Perigee 5/6 9 ft. rods have a butt dia. of .500", the same dia. as my same series 9 wt., myself and everyone else that have tried or bought one just love them, especially as a stillwater trout rod, lake or salt.

Matt,
Whether to install a butt extension “tube” over or inside the butt of the blank is a 2-sided sword. While a larger extension tube over the blank is inherently stronger, that stronger section concentrates more stress on the blank itself where the extension ends. Conversely, a smaller extension tube inserted into the blank will inherently be weaker but puts less stress on the blank itself. Kinda D if you do, D if you don’t.
As many of you know, I love building and fishing rods made from my stock of NOS Conolon blanks. But the models, lengths, actions and powers are rather limited. Unfortunately, the lighter powered blanks which I prefer for ULs are typically under 6ft; I prefer 6.5 - 7.5ft. I have had great success making 14in butt extensions by taking the butt section of an “identical” sacrificial blank and inserting it into the butt of the main blank (the faster the taper = the shorter the extension will be). As Ron mentioned, I also wrap the end of the blank and also further up the blank where the inserted section ends for added insurance. The inherent identical tapers produce a perfect ferrule. The attached photo shows how the strengthening wraps can serve other purposes as well, in this case a Norman Miller Hook Keeper. This rod is 7’4” and 4-sections. [www.rodbuilding.org] Although that is not applicable to your situation / desires, the joint can certainly be epoxied. Bonding the two together certainly reduces the need for perfectly tapered mating surfaces.
I have also built a number of heavier rods for saltwater Calico and Yellowtail (up to 30lb) which needed extended butts. On these, I bond a proper OD thin-wall aluminum (preferably 2024) tube 2 - 4in into the butt of the blank with 2 - 4in extending out of the butt and bond another proper sized ID tube of the required length over that. Designed properly, the reel seat can be mounted directly over the joint to help counter any stresses. But again, that would not be appropriate for your fly rod.
With your 6WT fly rod, you should be confident inserting the extension into the butt of the blank, and properly thread wrapped should insure such.

Mark Talmo
FISHING IS NOT AN ESCAPE FROM LIFE BUT RATHER A DEEPER IMMERSION INTO IT!!! BUILDING YOUR OWN SIMPLY ENHANCES THE EXPERIENCE.