Hi Rolf,

have a look at http://shop.ezentrum.de/2461261/sTVeLqG5...amp;artid=71646

It is in German, but it is a CFRP tube for about 150mm diameter and 5m length, or not other crossections with same perimeter. It gives you a nice +-45 basis (which shoud be topped by some UD cloths). It is certainly not the cheapest shop, but it gives you an idea (it is certified for aircraft structures). Correctly done you dont need a dolphin striker = less nasty drilling in CFRP. Regarding engineering: Well I cannot give you full engineering support (but do you relly need it?), but some stress calculations, sizing and so on. But not within the next two weeks. Just let me know.

Cheers,

Klaus