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There was a question asked about swelled butt rods, here are some answers:

I think it's pretty much a trial-and-error kind of thing to transform a "straight" taper into a swelled butt.  But, to save you a couple errors, maybe you can use some of my trials.

I like  a  swelled  butt  that  increases  the  diameter  about  .100" (.085" in a rod shorter than 7 feet ).  The swell itself would cover an area ahead of the grip of about five inches.  So, on the rod's original taper, measure five (or five-and-a-half) inches forward of where you want your front cork to be, and begin the swell back to the cork.  You will need to interpolate between stations on those rods whose five-inch dimensions do not fall neatly into your finished measurements.

The swelled butt will leave you with an enormously oversized grip.  So, in order to reduce as much weight as possible through the handle area, I then turn the blank under the cork and reel seat down to a 3/8" dowel.  You can taper this down immediately behind the forward-most cork.

Now, doing all this will alter the action of the original rod somewhat, but I have always found it to be an "improvement" of sorts -- mostly, in terms of the rod's maximum capacity.  A personal thing, at that point, 'cause I am not a great distance caster.  (I figure that's why I make the next rod-size up.)  (Bill Harms)

    Garrison had a method for calculating the amount of swell he wanted in a rod.

    Graph the taper dimensions on paper.  Extend the taper to determine what the dimension of the extreme end of the butt should be (the part at the very base of the reel seat).

    Use this measurement for the diameter of the butt under the hand-grasp and reel seat (IE: the last 10 inches of the rod have a uniform diameter and no taper).

    Swell the rod dimensions from the last measurement 2.5" or 5" in front of the hand-grasp to the diameter under the handle.

    Dickerson and Payne approached this a little differently.  If you look at a large number of their tapers, you'll notice a uniform diameter under the handle of .345 (my theory is because they used mass produced hardware with an ID of .345, and made every rod to fit the reel seat).  Off hand, I can't remember how far from the front of the hand-grasp they started the swell, but look a taper in the archive to figure it out.  (Chris Obuchowski)

    General rules of thumb - .050 to .060 mild swelled butt, .080 distinctive swell, .100 and up flashy looking swell. Seems like most Paynes had about .050 swell to them (some none at all though).  Some  makers  used  a  standard   butt   dimension (IE: .375) - all of the hardware was uniform that way.  (AJ Thramer)


Just wondering how list members handle the grip and reel seat when pertaining to a swelled butt rod.  Do you drill the grip and reel seat hardware to accommodate the swelled portion?  Or do you turn down the portion of the blank under the cork and reel seat to accommodate the grip and seat?  I would suspect that by turning down the butt section this would, to some effect, eliminate the whole reason for introducing the swell in the first place.  Thus affecting the way in which the rod was intended to cast.  Your input and suggestions are always appreciated.  (Robert Cristant)

    I always reduce the size of the shaft under the handle and reel seat regardless of whether I build a swelled butt or not.  There's just no reason to be carrying all that unnecessary weight under the handle.

    I slope the dimension on all my butt sections down to 7/16" beginning just under the first cork.  You mention that this practice may "eliminate the whole reason for introducing the swell," but that would depend upon what one takes the "reason" for a swelled butt to be.

    Surely, a swelled butt stops the action of a rod before the grip (if that is what one is after), but that would remain the case even if you turn down the diameter beneath the grip.  For my dough, I just like the looks of a swelled butt, and that would be my only purpose.  (Bill Harms)


To make swelled but forms, I used large, internal hex head bolts with a large smooth shaft and threads only at the very end like the ones on Thomas Penrose's page to build my forms (actually I built my first forms from the plans on his awesome page). The reason I mention the bolts is that is the only modification I made and because some of you out there use Garrison style forms (push-pull bolts all on one side) and other inventions, I don't know if this method will help you guys or not.

The first thing I did was take my bolts for the first 4 or so stations on the butt ends and I ground a relief groove in them, the reason for this is that as you spread your forms the bamboo strip will eventually bottom out on the bolts; the groove in the bolt gives you that little extra space you need. This may take several attempts before you get a deep enough groove (determined by how gutsy you are and your taper) in the right spot (center of forms for the given width).

The next thing to do is get some shims to put in by your pull bolts (These will take the high stress of your small push bolts), they must not stick up far enough to hold up the strip. Set them in up to the last station aft of the swell, now tighten down the bolts ahead of the swell, this includes the station just ahead of your last shim. You may have to use a LARGE C clamp to help you with this bolt. Now tighten down the last couple bolts behind the swell, you will definitely require the aid of your LARGE C clamp/vise/friend. Keep in mind that behind the sell will be turned down after to accommodate a reel seat and grip anyway.

Remember to split your strips larger than normal!!! The swell gobbles up a lot of bamboo.

PLEASE NOTE: Don't try this if you are worried about your forms, I don't want to be responsible for someone ruining their $800 forms and saying "Shawn told me to do this". I would feel terrible! All I can say is that MY forms held up fine, but mine are home made and are very strong. I was desperate to try swelled butt rods and this was feasible to me. Your swell is limited only by your courage and design of your forms. I've pushed mine quite far and I was happy with the results. The other option would be to build a short swell form.

The swelled butt rods I have built are light(or FEEL very light) and are fast action rods, although not everyone likes the action. Un fortunately any pictures I had of my swells were lost when my computer dumped. The Thomas And Thomas tapers are very extreme swells and may be a bit too much for your forms. The FE Thomas 7' 3 wt that Reed posted a while ago or any of the swelled FE Thomas rods) work nicely for a first attempt or the milder Grangers, Heddons and I believe some of the Dickersons have tiny swells which may be a better starting point as they are less acute and smaller. I believe Danny Twang modified a Sir D to have a swell??  You could experiment with Hexrod and existing tapers. Good Luck!  (Shawn Pineo)


I've noticed in going through some of the tapers in the archives that the numbers for the swell are left of and a note is simply inserted saying that the swell is not included. Is there some kind of accepted method/formula for adding a swell to an existing taper or is it strictly trial and error thing?  (Bill Walters)

    I think it's pretty much a trial-and-error kind of thing to transform a "straight" taper into a swelled butt.  But, to save you a couple errors, maybe you can use some of my trials.

    I like a swelled butt that  increases  the  diameter  about  .100" (.085" in a rod shorter than 7 feet ).  The swell itself would cover an area ahead of the grip of about five inches.  So, on the rod's original taper, measure five (or five-and-a-half) inches forward of where you want your front cork to be, and begin the swell back to the cork.  You will need to interpolate between stations on those rods whose five-inch dimensions do not fall neatly into your finished measurements.

    The swelled butt will leave you with an enormously oversized grip.  So, in order to reduce as much weight as possible through the handle area, I then turn the blank under the cork and reel seat down to a 3/8" dowel.  You can taper this down immediately behind the forward-most cork.

    Now, doing all this will alter the action of the original rod somewhat, but I have always found it to be an "improvement" of sorts -- mostly, in terms of the rod's maximum capacity.  A personal thing, at that point, 'cause I am not a great distance caster.  (I figure that's why I make the next rod-size up.)  (Bill Harms)


I am interested in making a 8 wt and it calls for a swelled butt,  my form cannot do that or can it?  How do I compensate for this in my form settings?  (Bruce Combest)

    You can attempt it with your current forms.  Arrange the station spacing so that one station falls just before the swell begins, or is about 12", 13", or even 15" from the butt end of the rod.  Set that station first, and crank the next station open as much as possible.  It's amazing how much pressure you can put on your forms with a push screw.

    Lemme try an example. 

    8' 8 weight

    0-65       xxx
    70"        .322
    75"        .330
    80"        .346
    82"        .355 (beginning of swell)
    85"        .390
    90"        .390
    95"        .390
    96"        .390

    If I were doing this rod, I'd start with some math.  Instead of setting my forms at 65, 70, 75, 80, etc. I'd set the forms at 67", 72", 77", 82", 87", 92", etc...  It really isn't hard to figure out.  You'll have to interpolate between the numbers you already have to come up with new settings.  Set stations 67 - 82, then crank 'em open at station 87".  Chances are good you can get them to the desired numbers.  It will change a compound taper slightly, but probably not so much that you can tell.

    The alternative is to allow the swell to fall over 5 inches instead of two or three.  That works fine as well.  (Harry Boyd)

      Just one or two things to add to what Harry said...

      First, be sure to double check your forms not only at, but also between stations for ten inches or so before and the same after the swell.  The stress on the forms from cranking them (depending on materials, of course) can be great indeed.  I had this problem with a swell on mine a few months ago and went nuts trying to figure it out until a list member who knew what was happening let me in on it.  That particular thread is on Todd Talsma's tips site if you are interested in specifics.  There are, as I gather you gather, special swelled butt forms, but that is out of my reach for now.  Perhaps I will try to build a set of wooden ones someday... anybody have any thoughts on this?  Anyhow, be sure to double check your measurements against expected slope per inch.  You can actually end up with a wave in your rod measurements.  (Carl DiNardo)

    I have a homemade steel planing form with stations on 5" centers, and have made several swelled butts with it.  I wanted the swell over 2-3" instead of the 5" my form would allow.  My solution was to find a washer that was the thickness of the space I needed between my forms at the bottom of the swell and to really crank down on the stations above and below the swell.  The rods look great, but without stations at 2.5" centers, I wound up with a few thousandths of wobble in the taper between the stations above and below the swell.

    Alternatively, you can make a swell by inserting wood between the bamboo strips as Jeff Wagner did on some of his recent presentation rods.  I am just varnishing a swelled butt made this way that I had glued up before I had a chance to look at Jeff's work, and apparently took a slightly different approach than he has used.  Mine is about as radical as Jeff's appear to be since I wanted to use the end of the blank as the reel seat, but there's no reason you couldn't do a more modest swell the same way.  (Robert Kope)


Having never built a rod with a swelled butt I was wondering just how far in front of the grip does the swell start, how fast (slope) should it climb, how far forward of the grip should it reach it's full diameter and is there a ratio that one uses in calculating the swell in relation to the diameter of the rod at that point without a swell? Wow! That maybe the longest and biggest question that I have asked! I think I hurt my brain on that one.  (Patrick Coffey)

    There are no standards that I know of, in my shop, instinct prevails, I just go with what seems right with no scientific foundations at all. I tend to shoot  for 60 to 80 thousandths or so, maybe less on a smaller rod, more on a bigger one.  (John Channer)


As long as I have been making rods, I have never made one with a swelled butt.   Ready to mill the butt section for a Payne 98 taper.  Was wondering what effect it would have on the rod if I swelled the butt.

Any one tried it on this taper?

What overall effect does swelling the butt have on a rod?

How far out in front of the grip should one make the swell?  (Joe Byrd)

    It quickens the taper. Thomas & Thomas makes theirs very short and dramatic. On a standard planing form the swell will be quite long. To make a short one you need a beveler or a form made to swell the butts. Golden Witch has them I believe.  (Marty DeSapio)


I am interested in building a swelled-butt rod with wooden inserts in the swell zone.

I have seen pictures of these insert strips in butts, but as I have never seen one in the flesh I find it very hard to visualize just how to go about making and fitting the inserts.

We have some native timbers here in Tasmania which would, I believe, lend themselves admirably to the purpose myrtle, huon pine, blackwood, meleleuca, cedar and others.

Can anyone help with (a) url's to sites with this sort of info or (b) actual direct details.  By all means do it off list if you are concerned about bulk.  (Peter McKean)

    I have looked into doing the same thing.  At a rummage store I found an old rod that had the inserts.  After taking it apart, I found that the strips were not strips but instead the handle was solid and the bamboo strips were fit into the wood. It would appear that six sixty degree grooves are made in the handle and the bamboo is fit into the grooves.  I spoke with another rodmaker about how he did it.  He told me the same thing.  Turn the wood handle to shape, then use a triangle shaped file and slowly cut the grooves.  Hardest part according to him was to bind the strips down tight into the grooves. I haven't yet done this, but it is on my list of things I'd like to do. I'm sure there are other ways too.  (Scott Grady)

    Jeff at Gnomish Rod Works is doing this with a series of rods. The process results in what is called a mortised rod. He is using purpleheart as a filler between the strips. He is a nice guy and I am certain would be happy to help. His email is Gnomish Rod Works.

    You are welcome to tell him that  I gave you the name and email. Good luck with the new project.  (Dewey Hildebrand)

      I'm visualizing the insert when complete, looking at the butt end as 6 flat sided pieces/slats with 30° angles on both sides of the lower edge coming together in the center. The tip end of the slat would have to be tapered to a point midway of it's thickness. The length of this taper will be the length of the swell. The width & thickness of the slats will determine the diameter of the 12 sided handle. When inserted and everything glued, trim/turn/sand to round.

      Clear as mud? I may even try this.  (Don Schneider)

        You could always just use rectangular strips and the butt would become hollow-cored. 

        Here is a drawing of what I mean. 

        Freaner, Claude Instert ButtFreaner, Claude Insert Butt2Here’s another drawing as well. 

      Freaner, Claude Extended Butt(Claude Freaner)

        If you use individual pieces, they have 90 degree sides, square in other words. 6 60 degree angles on the bamboo strips makes a full circle, the only angle left that can be used is 90 degrees. The only math class I ever paid attention to was geometry, which is a good thing for both rodmaking and carpentry.  (John Channer)

          You are right. That is why I said the bottom edge of all the insert strips would have to have a 30° bevel on each side. When glued together, you have 6-60° grooves for the bamboo to fit into. If the  handle  was  to  be,  say 1.25" D. The width of each slat would have to be 5/8"+. The thickness would have to be enough so the top surface of the bamboo was also 5/8" from center.  (Don Schneider)

            I have to agree with John on this one. When I talked to Jeff Hatton regarding this (and he makes them almost exclusively), he said he used square strips. They were tapered to a point on the sander and the bottom side had a taper similar to the rod at that point. I have never tried this, but that is what the person I know with the most experience at this says.

            Robert Kope made a beautiful wooden insert rod that he showed in Idaho Falls FFF last year. Maybe he will chime in?  (Bob Maulucci)

              I think it can be much simpler, you needn't bevel the wood inserts.  If you look at the cross section of a hex rod, all lines are (across two strips, from side to side) are straight.  Meaning, you can use straight, flt pieces of wood.  I have done this on a couple of rods and it is much simpler than you might imagine.  I simply took two sheets of wood (for the inserts) and sanded them to a very fine taper.  I used rosewood. The thickness of the wood (at its thickest point was the same as the bamboo (at that point, for symmetry).  The taper on the wood inserts has to be very, very gradual and work out to a very fine point (it will look sort of like a plane blade/wedge).  The taper over ~2-3 inches, but the length, of course, will be determined by how far out you want the swelled butt.  I then cut the wood wedge into several strips lengthwise. When I glued and bound  up the butt section of the rod, I simply inserted the rosewood between each piece of bamboo.  One piece went all the way across the rod, from one flt to the other, the remaining pieces were only halves.  If the taper and point of the wood is fine enough, there will not be a empty space above it, but this will also be dependent on how tightly you cinch down on the binding at the beginning of the inserts.  I used inserts long enough to also serve as the wood spacer, cool effect.  I have no idea how these inserts effect the action, but must stiffen it up considerably.  Have another partially done, will try to take a couple of photos.   (David Smith)

                Several folks wrote asking to see the photos of the rosewood inserts. As you can tell, this section was just glued and has no finish.  Hope you can see (from the end) how it was done.  I described it in a post yesterday, can repost if someone needs it again.   (Link to photos)  (David Smith)

                  Thanks for sharing, David. I appreciate your openness. Your pictures answered all of my questions. Am I assuming correctly you could use the same technique if you just wanted a small swell of .050" or so using smaller/thinner  inserts  of course?  (Don Schneider)

                  What do you all think of the practicality of adding a very thin cork handle over the top of this, and forming the end of the rod into a reel seat?

                  No doubt its been done before - anyone want to put their hand up to say how it worked?  (Dave Kennedy)

                See for yourself. 

              Kope, Robert Cocobola InsertThis was done a little differently from David Smith's. The butt is solid and all the wood strips meet in the center.  The wood I used is Cocobolo and the reel seat hardware is from Struble.  (Robert Kope)

                Thanks to you both for your help in providing the pictures of inserts.  My spatially challenged brain now seems to grasp the elements of the required geometry, and already I can see a dark flamed rod with inserts of huon pine burl, gleaming in its superiority over the plainer denizens of the bench, like Meg Ryan at a convention of bag ladies!  (Peter McKean)


Now that I have a planing form that allows me to created swelled butts, I'm wondering.  Wondering if we can get a discussion going that centers around the benefits/drawbacks and design issues related to swelled butt rods?  I understand that the effect of adding the swelled butt is an abrupt termination of the action of the rod. If I take an existing rod and add a swelled butt to it, how to I determine where to add the swell?  (Todd Talsma)

    A swelled butt goes somewhere below the belly button and above the knees.  Sorry, couldn't resist.  :-)

    I've started adding a slight swell in the butt of most rods I build these days.  I find that leaving the first station above the cork at its normal dimensions -- say .290, and adding the swell from there to the butt end makes a big difference in the way mid or tip flex rods perform.  As I'm sure you know, butt-flex or parabolic rods with swelled butts are likely to perform radically different than their straight butt counterparts.  Usually worse, but not always.  For instance, the PHY Midge and Perfectionist tapers actually become rather  nice rods with swelled butts.  Well, the Midge was nice to begin with, but the Perfectionist has always felt weak to me.

    To answer your question directly, I begin the swell at 70" on 7' rods, 75" on 7' 6" rods, and 80" (or 82.5") on 8' rods.  (Harry Boyd)

    I try to start swells at about 5 to 7" above the start of the grip. I too find that it doesn't work with parabolic tapers. The semi parabolic tapers like Garrison, Howell and Winston all react favorably to swells.  (Robert Sherrill)

      Those of us who work with the swelled butt all have our favorite little formulas, and whatever one likes is "right."  My preference is to begin the swell 3" in front of the grip position and increase each strip by .040" over that span.

      As for fitting the cork and reel seat, I then taper that swell back down rather steeply to a 5/16" dowel, beginning under the first cork. Surprisingly, although a swelled butt is said to stop the action, I can still feel my rods working slightly under my hand.

      So, the amount of interruption of the action would seem to be a function both of how great the swell is as well as what is done with the cane under the grip.  These two seem to be factors, but exactly how they play into the "formula," I'm afraid, is anybody's guess.

      I recently made a version of the "Driggs" rod (the taper for which I lifted from an existing rod), but used the above technique to form a swelled butt. The resulting rod is somewhat more authoritative than the original and I much prefer it.  Other PHY rods may or may not respond the same; I wouldn't know.  (Bill Harms)

    I really like a large swell over a short span.  I usually have a swell of @ .100 over 2" or 2 1/2".  the decision to have the swell over 2" or 2 1/2" is based on the length of the cork grip.  If it is and even numbered grip (4", 5", 6" etc) the swell is 2".  If it is an odd numbered length (5 1/2", 6 1/2" etc) it is a 2 1/2" span.  I guess it can be best explained "a la" Thomas & Thomas.  (Robert Cristant)

    It's all relative to the length of the grip. You need to put the swell immediately in front of the handle. If one grip was 5" long and another was 7" long then the swell would need to be changed by 2" or it would be in the wrong place. (Jim Bureau)


Just thought I'd pass on a little something that might spare someone else some aggravation.  After building several rods with a Leonard type swell (>.080) on my conventional Garrison style forms I finally stripped the form threads on a station.  I knew it wasn't a matter of if, it was a matter of when, and how many rods could I get away with it.  Well, 11 to be exact.  So, my forms are at the machine shop getting retapped and I'm looking for recommendations for forms that will accommodate a swelled butt.  (Gary Williams)

    If you plan to make only swelled butt forms, you might consider using a triangle file and just work the swell permanently into your forms.  (Bob Nunley)

      Or you could thin down the form in the butt end (on the sides)  to reduce the stress from bending the forms  (Al Baldauski)

    Assuming that your forms are 3/4" square, you could drill a 1/4" hole in the middle of the top of each form in the area of the swelled butt.  Then make a saw cut from the outside in to the hole, creating a "weak section flexure"  This would make it easier on the adjustment screws.  I'm an EE, I'll let the ME's comment on the viability of doing this.  (Ron Larsen)

      From an ME - that will work.  The question is where to place the holes, how many, and their distribution.  (Frank Paul)

      From another ME:  keep in mind that the flexing will concentrate at the locations of the holes, and the area between the holes will remain fairly straight.  Size and spacing of the holes, and the distance from the edge of the hole to the mating face will greatly influence the shape of the curve.  (Tim Preusch)


What's the purpose of the swelled butt?

I know some tapers call for them. But why??

I looked for info in the archives and couldn't find any.

The reason I'm asking is because I should be done tapping the forms today and I know I'll be cutting the groove soon. In lieu of that, I'm thinking about grooving out the one side so as to be able to make swelled butts.   (Ren Monllor)

    I'm going to let others better versed in tapers and rod actions answer the "purpose" part.  My forms have push/pull bolts and dowel pins on 2.5" centers for about half their length starting at the large end of the butt.  That lets  me adjust for modest swells.  If the taper doesn't have a swelled butt, I just don't use the intermediate screws, leave them loose.  (Neil Savage)

    There are numerous reasons to make a  swelled  butt. Appearance - some people just like the way it looks. Some rodmakers use contrasting wood between the bamboo and it looks really nice. Utility - some parabolic rods flex way down into the cork handle, and the top couple of rings actually develop cracks at the glue lines joining the rings together. A swelled but stops that from happening. Part of the taper design - the designer wants the action of the rod to stop abruptly at that point the swell starts. I have a 5 ft. small stream rod that I have stretched out the swell so that (I think anyway) the energy of the cast flexes into the swell and is returned when the rod springs back. Take your pick for your reason if you want to make a swelled butt rod.  (Darryl Hayashida)


I decided to make my first swelled butt rod and have a question about how small to turn the butt before I completely loose too much strength.  My reel seat inserts have either 5/16" or 11/32" holes and it looks like if I drilled them any larger there would be very little wood left at the mortise. And then there is the cork - it must also end up in the thin side.  How do you accommodate the cork and insert and still have enough cane diameter left for strength.  School me if you would please.  (Tom Key)

    Turn down the cane that will be under the reel seat to 5/16.  (Steve Weiss)


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