Using biaxial tape to replace keelson and stem lamination on off the beach trimaran

[Corley]

Hi,
I'm proceeding quite well with my Kraken 25 rebuild and have just finished battening the mould I was looking at the keelson yesterday and the stem lamination and cant help but think its unnecessary weight that could be easily replaced by an epoxy fillet and biaxial tape. The hull shell is going to be laminated in 3 layers of paulownia veneer 2.2mm thick. I've pulled a few test laminations off the mould and have been impressed with how stiff and light they are.

My thoughts are that I should construct the hull shell as planned but lift the hull shell with the transom in place but without the keelson or stem lamination. Farrier trimarans join the two hull halves along the centreline with a similar technique so I can't see there will be any problem. Anyone have any experience with a similar scenario? The hull is very lightweight (estimate at around 50 kgs max) so would be similar to floats on a larger trimaran.

[catsketcher]

My thoughts exactly Corley

It is pretty hard to find anything lighter than 440gm double bias so I would do one layer of this 100mm wide on top of an epoxy fillet. Do the same outside and it should be bulletproof. Make sure you use double bias and not biaxial. Biaxial is good stuff but half of the fibres will be running with the seam and so be useless. Double bias has both fibres running over the join.

cheers

Phil