Quote:
Originally Posted by Ken
I think the stiffness is generally considered to be a boom body issue and not a tail issue, so carbon tails don't sound like a worthwhile idea to me.
|
Wrong. A carbon tail inserted into an aluminum boom stiffens up a lot more the entire boom as compared to that with an aluminum tail. The carbon tail does play a key role in boom stiffness.
Quote:
|
In time carbon fatigue will surface. I have had two 100% carbon booms break at the head, but only after several years of use.
|
True. My North Sails racing 220-260 carbon boom lasted 5 years before breaking at the junction between the head and the body tubing.
Quote:
|
On the other hand, carbon will most likely last much longer than aluminum.
|
Quite the opposite for me. An all aluminum North Sails boom lasted 15 years before snapping at the junction between the head and the body tubing.
Quote:
|
And if you consider that you could possibly replace your aluminum booms every other year and spend less money than replacing your carbon booms once every 6-8 years, aluminum doesn't sound like a bad idea, especially if you are a fresh water sailor and use the booms on medium to small sails.
|
True for boom less than 2 m long and if you're not a heavy weight racer. Otherwise, a carbon boom is stiffer than an aluminum boom of the same lenght. The german Surf magazine has tested 24 all-/hybrid-aluminum and 7 all-carbon booms in their August 2011 issue (*). Lab results have shown that carbon booms are 2x to 3x stiffer than aluminum booms : compare stiffness value of 60-70 N/mm of deflection when a weight of 40 kg is hanging at the middle of a carbon boom with that value of 20-30 N/mm of deflection obtained with an aluminum boom under the same conditions. The Severne Enigma carbon boom and the North Sails Platinum carbon boom are the 2 stiffest booms of the test.
Cheers !
JM
(*):
http://www.surf-magazin.de/service/a.../surf-82011-2/