Bouke-Witchcraft said..
We had this problem for years up to about 14 years ago. Getting fed up with boxes full of bent and broken extensions I had an intern examine if we could not solve this. Examining bent extensions we quickly found the solution: Extensions always bend sideways, where the holes are and they are the weak point. With alu extensions there is always one holes squashed and the other stretched. I presume because they thought the biggest force on an extension is the downhaul. But in use the sideways load of a wave in the sail is much bigger then any down haul. He calculated that just turning the holes 90 degrees made the extension 96% stronger for the side ways load.
you don't need any finite element simulation to know that the holes seriously reduce the thrength of the construction.
But it is good to see in clear daylight.
I am so fed up with the some of the big windsurfing manufacturers.
They produce low quality gear but charge premium prices.
What really pisses me of is 1.) that some of the problems could easily be fixed by them.
2.) that this get you you in life threatening situations. Just because some plastic part of a boom or extension breaks because of some cheapish screw corrodes and cracks the plastic. (e.g. Happend to me with all the duotone parts. The plastic is to brittle)
3) They are so ignorant to react to these problems.