I just recieved a 4 piece Rainshadow fly blank to build. I sat down last night and started checking for the spline location. The tip and following two pieces were easy, but the butt barely flexes. My gut tells me there is no effect at this point. Am I correct or am I not?
Since this is my first hand made rod I don't want to assume anything. When locating the spline the pieces flex and roll to what I consider the "weak" side of the blank. In that flexed position, do I align the guides in the inside or outside of the arched blank?
Also, is there any rodbuilders in the Seattle area that wouldn't mind a silly question or two from time to time?

There is not "correct" position for the spine. Where you locate your guides in relation to it will determine the particular characteristics you will get from that rod.

Each section affects the spine, but most of the effect is created by the upper half, or at most the upper 2/3rds. If you cannot find it on the butt section do this - sight down the section and locate the natural bend of the piece. Mark the spine as the outside of the bend. This won't necessarily be exact, but it will be close enough to work well with the other pieces.

A reminder - the spine is the outside of the relaxed curve. Roll the pieces until they come to place where they want to stay put, not where they jump or kick. The outside of the that curve is the effective spine.

I think you will get a nice rod if you put your guides directly on the spine. You can do it opposite of that and also have a nice rod, but the casting characteristics will be different. Twist is not a factor as the guides, being on the bottom of the rod, will hold it stable during the backcast and fish fighting.

........................

Thanks Tom, I appreciate your advice.

I'll add a sentence or two to what Tom didn't say. Some folks like to put the guides on the spine as Tom suggested whereas others like to use the other side. As I define the spine it's the side with more stiffnessand therefore more strength and I think it also conforms to Tom's definition as the outside of the slightly curved bend of the blank at rest (sometimes so slight you can't see it). The reasons usually given for this are if you put the guides on the spine then you'll have the stiffer (stronger) side to the fish when fighting it and the weaker side will be facing the line on the backcast. Some folks like the opposite arrangement so that the weaker side is facing the fish and therefore protecting light leaders and tippets whereas the stronger side faces the line on the backcast and gives more strength when casting the line. I use the second arrangement on my lightweight full flex trout rods and the first on my heavier bass rods--FlyDoctor

I saw this same definition on another board. From what I know of spine it is not the stiffest side of the blank. Spine is the outside of the relaxed curve which may be or may not be the stiffest side.

The spine is not the outside of the slight natural curve of the blank, it is the outside of the relaxed, but pressured curve and that is not the same thing. The stiffest axis is usually found along the outside of the blank's natural bend.

People often make the mistake of thinking that the stiffest and softest axis's are opposite each other. They rarely are and there is no certain relationship between the two. Sometimes they are 180 degrees apart, sometimes 90, sometimes 160. It varies from blank to blank.

................................

Tom--This definition has me confused--how can it be both relaxed and pressured at the same time? Seems to me that if is flexed under pressure it sure ain't relaxed and vice versa. I still go by the method on page 9 in L.A. Garcia's book "Handcrafting A Graphite Fly Rod" and I agree with you that this often does result in what appears to be more than one spine and they often are not 180 degrees opposite the softest axis. When this is the case it really makes it more difficult to figure out where to put the guides. I have used both the softest side and the stiffest side as described above depending on the type of rod I am building--FlyDoctor

To find the spine you will pressure the rod and when the flexed rod rotates to a spot where it settles into a sort of locked position, that will be your relaxed curve and is the place the blank wants to stay when pressured. Yes it is under pressure when you do this but is known as the relaxed curve.

The natural bend of the rod is found with the blank not under pressure. The stiff axis is usually along the concave bend. You can try this for yourself and see what he's talking about.

From my reading of the various articles this has become pretty obvious. And there is only one actual spine on the rod and it will be the axis that is found as described above in the first paragraph. I have found that the vertical type spine finder makes it easier to find the true effective spine.

I'd also agree with Tom that blanks almost never have the stiff and soft axis opposing each other. That would make things too simple! When I find a blank where they are, I buy it! Most times I don't find such blanks.

Nothing against Mr. Garcia, but I thought his spine definition was way off the mark. At least as far as how most rod builders define it.

Amen. I think maybe we need a better term than relaxed curve as it is obviously confusing. I can see how. Outside of soft curve? I have also heard it called the outside of the stessed curve at rest. Just an idea.

Confused more than ever, am also planning to work on a 4 piece fly rod, I wonder if it is better to work on a one piece or even two piece blank mark the spine then cut down and create my own ferrules?

Just a thought.

Felix,

No way. It is alot harder to make ferrules than to find a few spines. I assume YOU have a method YOU use now to find an axis to place the guides on. Using your method find the spine or axis on each section. Mark them, however you do now, and put the sections together, lining up the spine marks. Check for the spine on the assembled rod. There is a good chance you will find a "new spine" off of the axis of the marked sections. I f there is, remove the original marks and put new marks on each section following the new spine location, while the blank sections are still assembled. It may sound as though you can skip the first part, finding the spine on each section separately, but don't. This alines the stiffest axises close to each other, assuring the strongest axises are lined up when finished. Easy to do, hard to explain. Hope that helps.

Bill Doherty

Felix

I should have added: How you apply the above information about inside curves, outside curves, stiffest axis, is up to you. After I find the "spine" on a muti-piece blank, then I worry about which axis to place the guides on, or opposite, or perpendicular... you get my point.

Bill Doherty

Thanks guys, my response was more out of frustration, it happens that I was about to wrap my last two guides then I looked over this topic and realized I was off the axis had not properly check the spine had to do the whole thing over.

Better doing it right than having it wrong.

Thanks again

Thanks guys, my response was more out of frustration, it happens that I was about to wrap my last two guides then I looked over this topic and realized I was off the axis had not properly check the spine had to do the whole thing over.

Better doing it right than having it wrong.

Thanks again

Wrap piece of tape on rod.
Rod butt on hard floor.
Rod held at an angle to floor.
Lay tip in one hand without grasping the blank.
Press down the blank 1/2-2/3 way up the blank with the other.
Rod rolls itself over.
Mark the tape on the side of the blank facing the CEILING.
Repeat two more times to make sure mark is in right spot.
Tweak the mark.
Put spinning guides on side opposite tape.
Put casting guides on same side as tape.

Or you could just say put the guides on the CEILING SIDE or the FLOOR SIDE.

This even works with most crooked blanks.

No need to define terms, just do the drill.

The spine, spline, axis, hard side, soft side thing has been beat to death. Who's right, who's wrong, who cares?

You tell'em Mike,

Thats the way I find'em. Just do that 4 times ,on each section, then once more after the sections are put together.

Bill Doherty

Sounds simple enough with the down to earth instructions Mike gives, but also remember what casting or fish handling characteristics are optimal for which axis the guides are placed. As Tom K. pointed out, we can determine best performance by taking advantage of the spine effect for guide placement. Maybe not always do you want the casting guides on the 'ceiling' side. One might take into account certain preferences for taking advantage even by placing guides at 90 degrees to a spine effect in some odd circumstances, or whether one would prefer fish fighting over casting distance??....maybe place them on the 'floor' side for some circumstances. That is why we play with the spine in relation to guide placement, and the terminology is more secondary.

Rich
Solyrich Custom Rods

About the only time I put casting guides on the floor side is on live bait rods.

I want the least resistance possible acting on the bait. The more the bait can move the longer he will live, especially in the ocean during slow trolling when you are pulling through swells. I want the rod to bend to the fish as much as possible.

Since live bait drags are set very low in the 3-5 pound range, there is no need to worry about the fish 'fighting' ability of the rod in the power area.

Mike speaks english, thank god! Not to say that I am not obsorbing the wisdom of the rod making gods. Thanks to all.

Rick, I live in Seattle and build rods of all types and wouldn't mind discussing related topics. Just bear with me on the time spent replying as I am pretty new/slow in the computer arena. Look forward to hearing from you. Joe