|The Ovi carbon boat is carbon on the inside and iI dont think it is vacuumed on. The problem has been the hulls have come out only 9kg underweight. Therefore to wet the carbon out they had put 11kg more resin in the inside laminate. The new boats may be better.
As a comparison the boat Gavin built for me was 20.9kg under weight – it has carbon both sides of the hull and the underside of the deck. He charged me £500 for all three layers of carbon pre-preg.
The carbon layer inside will make the boat retain its stiffness a lot longer, so it is a good investment.
Carbon cloth is fiddle to fit and a lot more difficult to wet out, that is why it is easier to use pre-preg, which fits dry into the mould than manually do a manual wet out – that it why Ovi has to charge more.
Charles, The first ovi carbon hull was around 9kg underweight but on the last two carbon boats I finished one was 18kg and the other had 20 kgs of correctors
Happy to back Phil on this one, having laid up the 15 laminates myself, I suspect for the first boat the carbon skin was added after the hull had been laminated conventionally, meaning the laminate needed wetting out afresh. With a conventional inner laminate I would be expecting to use about 9kg of resin, hence the weight gain.
Once Ovi’s were content with this technique the carbon may well have have been laminated at the same time as the rest of the inner skin making for little weight gain.
One of the advantages of carbon in my experience is that it takes up less resin for a given strength.
They could be even lighter if you go to unidirectional carbon. Higher labour costs though as you have to effectively lay up the boat at least twice…