Just a quick enquiry. What are you views on spining rods, especially matching the spine on multi section blanks, and the easiest way to do the job.

The method that I employ is to rest the butt of the blank / section on a sheet of glass, support the tip and apply pressure to the middle.

I have always said that spining is a necessity, but having read some recent threads I'm not so sure.

I don't bother with rod spine, instead aligning the straightest axis. This generally puts the most powerful axis (only a little more power, really) into the fish fighting plane. The spine ends up off to the side somewhere.

As far as finding the spine, what you're doing is fine. But on the shorter and stiffer sections can be tough. In that instance, you can fall back on just finding the straightest axis. There is mention of this in the FAQs here.

...........

Simon,
I always spine a blank in a similar fashion as yours. However, I put the tip on a hard flat surface such as a ceramic tile foor, a wood floor, or hard vinyl floor and gently push down with my finger on the top. The rod will usually bend in its preferred bendin plane. I then try to bend it in other directions and it will then rotate until it bends along what I (and many others) call the effective spine.

Since the rod blank "wants" to bend in that plane, I apply my guides either along the convex or concave side of the bend. For fly and spinning rods I use the concave side. I do this because I believe if the guides are placed in any other place of the rod, there will be a torque created when you cast the rod. What I don't know is the strength of that torque. I suspect the torque is dependent on the power of the rod, but there are probably other factors as well. My reasoning is similar to those who a spiral wrap to try to minimize the torque on rods using a casting type of reel.

I'm quite sure that you will find a large diversity of opinion on this matter on this forum. You should read everything you can and then decide for yourself on how you want to build your rods.

One other thing I should mention is that when I attended the Pacific Northwest Rodbuilding meeting last Spring, Don Merton gave a talk and discussed rod blanks that have a spiral spine. He advocated taking an "average" spine. In this case I'm not sure if the spine matters in that you can't esily find the preferred bending plane, that is, the the rod "wants" to bend in different directions along its length. If I ever encounter such a blank, I would probably follow Tom's advice.

Best of luck,

Mike Blomme

I always build on the straightest axis with the bell of any curve down, I don't worry about the spine/

Mike (Southgate, MI)
If I don't want to, I don't have to and nobody can make me (except my wife) cuz I'm RETIRED!!

SCJ wrote: "The method that I employ [when splining] is to rest the butt of the blank / section on a sheet of glass, support the tip and apply pressure to the middle."

IMO, just a minor but real caution would be: To be careful with thin-walled rod blanks, that you are not applying so much pressure against an incompressible surface as hard as glass, that you are causing some micro-fractures around the outer rim of the mouth of the female ferrule. If that rim has a perfectly sharp right-angle corner, rather than at least a tell-tale "bull-nose" round-over, then you can fairly easily concentrate a very large force on that very tiny corner. Rolling the blank can crush the corner, and propagate those micro-fractures axially in a radial fashion around the rod blank.

I’ll admit, it sounds like Cliff Hall has gone off a cliff here, gone off the deep end again, with his microscopic analysis of the rod-building world, now he’s worrying about some rare cause of future ferrule cracking. But grab your parachute and follow me over the edge for the rest of the story.

ANY glass plate that you use is harder, with respect to mineral crystal structure, than the resins or fibers in your rod blank, and can scratch the rim of the ferrule when you slide things around. Then when you apply downward pressure and a rolling force, you have a source of energy that can result in micro-fracture propagation. Since ferrule damage is mostly a cumulative, repetitive fatigue process, this is a slow process that does not catch our attention until months or years later, when we say, “Dang, how did that happen?” Lots of other possible explanations than my little worry, I’ll admit. But micro-fractures in the rim of a female ferrule initially generated while splining against a glass plate is certainly one of them.

Many years ago, I thought it was cool to use a glass plate myself to spline my 3-piece Fenwick Fera-Lite Ultra-Lite rod blank when I re-built it. It developed more fractures after my re-build in a few months than it had in years of prior use. It is impossible to differentiate the cause(s), but I have ever since suspected that rolling the ferrule rim against a surface as hard as a glass plate did not help matters any.

When splining by hand, I understand the importance of resting the butt-end of the rod blank or section against a surface that doesn’t introduce too much resistance against the rolling action of the rod spine or curvature. BUT, IMO, glass is way too hard a surface for that. IMO, any flat table-top is fine. I’ll use a magazine or a few layers of printer paper between the ferrule rim and the desk-top to cushion the rim. When I can SEE a little trail of indentation in the paper where the rim rolled over the page, I know that I did not crush the ferrule rim. The paper fibers buckled, absorbing that pressure – NOT my ferrule’s rim. …IMO, ceramic tile floor is as hard (dangerous) as a glass plate.

You can fairly easily see for yourself if your technique is causing problems. Just LQQK closely at the rim after rolling, and see if any signs of crush, powder, scratch, or crack are present on the glass plate or on the ferrule rim. If you HEAR a tinkling sound, the rod resin is cracking or crushing.

YES, I realize that technically, GLASS is an amorphous solid and does not have a true crystal structure. But a glass plate is capable of scratching a rod blank, and is more incompressible than the rod blank as well. If you are gonna bother spining (splining) the rod blank / sections, it’s better not to roll the rod against a surface that may introduce micro-fractures to the rim.

Alright, that part of the “Fantastic Voyage” tour of the microscopic world of rod-building is over now (I hope). … Here comes the elevator to take us back up, topside to the “Big Picture” level. … B)- … -Cliff Hall, FL-USA.

Don Merton or whoever is just plain wrong. Just because somebody gives a seminar doesn't mean they're qualified to do so. Rod spine has nothing to with rod twist, except when you bend a blank by hand. When it is bent by a fish, the rod will spin so that the guides are in line with the direction of the fish. If they're on the bottom already, there won't be any twist.

Same with casting. The rod will only twist in the direction of load if the guides are not in line with that load. Spine has ZERO to do with it.

The whole mess on rod spine, effective spine, average spine, marginal spine, strong spine, weak spine, upside down spine, and any other spine nonsense is among the worst things ever perpetrated on unsuspecting rod builders. Whoever started that nonsense to begin with deserves forty lashes with an ultralight blank.

I think we are all too anal on this topic. I do spin rods, but I also know most of the rod manufacturers do not, at least a few years back they did not.

Still, I do it, cause I am a bit anal, but do it simply, by standing rod on soft surface and pushing down so rod takes natural curve, doing several times to be sure of line. Then I put rod under slight static load to see the result, works well, but if I am off, not really a biggie, at least to me. Never had a complaint, and I have a few of these rods in the hands of beer buddies who like to find faults.

Hive