Loss of performance in Rods

[13Fisher1]

I recently read an article or letter in Trout & Salmon that modern materials used for constructing fly rods (carbon fibre, graphite, glass fibre etc) suffer from ageing that can result in rods losing their performance and "action" after several years.

My favourite rod I most use is an old Hardy Ultralite that i still cherish and whilst I have not noticed any degradation in action or feel I wondered if there was any truth in this article. I suspect that like most materials there will be some ageing or change in properties due to age or repeated stress.

Any input or facts here would be appreciated since like you I don't always believe everything I read!

[Traditionalist]

Theoretically it is true, but in practice you will not notice it. There is some degradation over time but it is due to usage, not age.  This is commonly referred to as "fatigue".  There is some data available on carbon fibre for aerospace and similar components, I don't know of any data specifically on rods.

If you do a search on "carbon fibre fatigue"  you will find a lot of stuff, but it is not really all that relevant to rods.  If you cast one continuously round the clock for several years at least you might find a measurable difference.


TL
MC

[13Fisher1]

Yes Mike, assume working life of rod is well within fatigue range of material, reminds me of study years on mechanics of materials and failure modes etc.... I have also worked in several aerospace projects so analogy is good one where they refer to cycles or hours for component life.
Thanks for the feedback and info., appreciated

[Traditionalist]

Yes Mike, assume working life of rod is well within fatigue range of material, reminds me of study years on mechanics of materials and failure modes etc.... I have also worked in several aerospace projects so analogy is good one where they refer to cycles or hours for component life.
Thanks for the feedback and info., appreciated

Most tests are in very high cycle ranges, ( up to gigacycles) and most rods will never even approach that;

http://www.sciencedirect.com/science/article/pii/S0142112305001015

TL
MC

[Traditionalist]

I have some data on bamboo and split cane fatigue if you want me to dig it out, but it's pretty boring really, and it simply proves that rods will become "softer" with use.  the "power fibres" in the cane suffer from fatigue.

Some old solid glass rods were prone to surface fibres delaminating after long hard use, but that was mainly a case of the resin bonding deteriorating at the surface, and not fatigue as such.

TL
MC

[Highlander]

My wife was just talking about the self same thing.
:roll:
Tight Lines

[alancrob]

can result in rods losing their performance

My wife was just talking about the self same thing.

Is it a bit like the brakes on the car? Until you replace them you don't realise how bad they were?  :?

A.

[alancrob]

my arm looses performance way faster than any rod

Try changing hands!  :getcoat

A.