In a message dated 97-10-22 05:11:56 EDT, you write:
> Hello everybody from Spain. I have recently joined the Rodmakers, and I
> will be very grateful if somebody could give me some information about
> Stress curves.
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I posted this last month, but with all the questions popping up
about stress curves, I decided to repost it. If everyone agrees
with my analysis, perhaps we should put it on the Web Page?
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In it's most basic use a stress curve shows you how close
a split cane rod is to breaking with the weight and length
of line you specified. Garrison believed 200,000 ounces
per square inch was a good, safe upper level. In reality
you can go up to 220,000 or 230,000 without any problems.
Garrison himself went up to 220,000 on his lighter rods.
Garrison believed that below the 140,000 point the bamboo
stopped flexing.
As you get deeper into stress curves you can begin to pick out certain
characteristics that tell you what kind of action the rod has, or will have
if it hasn't been made yet. A Garrison rod, which I consider to be slow,
has a well rounded "hump" near the tip and a fairly slow drop off as it
goes towards the handle. Let's see if I can do this with ASCII art.
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The rod that I'm always raving about, the Cattanach 7' 0"
4 wt, I consider to be fairly fast. It has a stress curve like this:
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The blip near the handle is the Cattanach hinge, and it greatly
enhances roll casting. Don't forget to put it in. I did and the rod
I made was a terrible roll caster. It isn't as necessary on longer
rods, but on shorter rods it's definitely needed.
A Paul Young Para 15, what is described as a parabolic action
looks like this:
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Looking at this rod, and never having cast one, I would guess
that it would feel fairly slow, due to the enhanced bending near
the handle, but able to throw a lot of line, due to the stiff mid
section. I would also guess that it could roll cast really well.
There are as many variations of stress curves as there are
rodmakers. This covers the slow, fast and parabolic actions.
Darryl Hayashida