Here's a question from the Volume 2 - Issue #4 issue of RodMaker magazine:
" . . . I have followed the debate on finding and using the spine
with great interest. Very briefly, in my mind, there are 4 main 'lines'
along the blank. When bending the blank, holding the tip and placing
the butt on a table, during the 360 degree rotation I encounter two
"stiff" (unstable) positions where the blank wants to move further down
into either of two "softer" (stable) positions. Trying to twist the
blank out of either of the stable positions takes a bit of force.
On most of my blanks the "built-in" curve of the blank follows one of
the stiff positions, very easy to notice on my Scott.
I have considered placing guides along either of the two stable curves,
because I thought that during casting this would stabilize the movement,
i.e., the rod would not have this tendency to twist away from the
unstable position. Words fail me here, but with your experience, I
think you know what I mean.
Any help will be greatly appreciated, so I don't spend several more
months wondering about what I do. . .Sigurd . .Norway
Glad to see that you realize the importance of utilizing the spine
in rod making. There are so many theories and concepts concerning
the spine that it is often difficult to make a dicision on the best
way to utilize it, let alone find it!
The spine of a blank, which is the outside curve when the blank
is in its relaxed position, is caused by the fact that the wall
thickness around the blank varies due to the intricacies of the
prepeg pattern and how it is wrapped around the mandrel during
the manufacturing process. In your case, I would suggest locating
the more pronounced of the "softer" positions and using that as
your reference point, marking the outside of that curve as the
spine.
As you have noticed, the stiffest plane or axis usually follows
any natural curvature of the blank, but may or may not be
exactly 180-degrees opposite the spine. In this instance, you
will have to decide what particular performance characteristics
you deem most important and locate your guides accordingly. If
casting is your main concern, some test casting with the guides
both on and opposite the sprine should be undertaken and will
make it easy where the guides should be located. If fish fighting
is the primary objective, you may find that locating the blank
so that the stiffest side is presented to the fish (this would
usually put the blank in a concave position following its natural
curvature as it is help parallel to the ground) yields the best
results.
I always strongly suggest attaching the handle in a temporary
fashion and taping the guides on the blank in various positions
relative to the spine and then going out and doing some test
casting and fighting/lifting. Doing so will teach you a good
deal more about how the spine relates to rod performance then
any amount of reading or considering theories ever will. Good
luck. ~ Tom Kirkman
Publishers note:
If you have any tips or techniques, send them
along! Help out your fellow rodmakers!
~ Publisher, FAOL
|
