Small trimaran with Tornado/Nacra 5.8 center hull

Hi Solgato,
Thanks for the tip, although that type of surplus is not available in Sweden, as we don´t have any airplane industries. Have actually thought of making my own sandwich flat panels with fiberglass, epoxy and 10mm 80kg for the floor and Divinycell 60kg for the side panels. Already have it in the workshop. Not as light as honeycomb though, but a lot cheaper. Want to make everything demountable, so thinking of using aluminium profiles to build a frame. Did this sketch yesterday, showing the rear of the main beam center tube. Open at the rear and closed in front.

Curious, have you sorted out your mast rotator issues?

 

Found that link. It’s a US supplier, but it’s interesting to see all the sandwiching options available.

https://www.carbon-core.com/

Regarding my rotating rig, yes I think I’ve figured out how it was originally rigged.

The designer and folks who spec’d the mast and sails knew what they were doing.

Somewhere along the line between owners the knowledge of how it was supposed to be rigged did not get passed down which explains why the last few only had it connected to the boom.

I will be making up a pair of 2:1 purchases similar to jib sheet control lines and running them aft through the clutches so I can lock the mast.

There isn’t a lot of room above the spanner to run the line you suggested to keep it from pivoting down as the boom yoke attaches and the sail gets fed into the track just above, so I may instead fabricate a ridged under support that anchors to the mast with a turnbuckle for adjustablility so long as it doesn’t interfere with other control lines.

Anyway, I have a plan now and will know/learn more once I get the boat rigged and launched this Summer.

Thanks again for your input on that.

 

Cooled down a little about the design of the cockpit, as it was a real overkill. This shallow version will anyway give some sailing dinghy feeling and something to stand on when hoisting the sails.
Found Exalite at an importer of packing material in town. Durable polypropylene panels, that only set me back 25USD/sqm. About the same weight as the planned epoxy panels at less than half the material cost. Well below my 15kg limit.

 

Slowly making some progress. Built the side walls for the cockpit, but realized they where clumsy in the lower corner and also a little to deep. Have just picked up the PVC profiles for correcting them. The trampoline will be swept around the side tubes to the keder rail and will be made with a pocket for 8mm EVA for comfort. Initially I will use the Nacra rear beam with 100x2mm extenders to get 4.7m beam. The sketch shows the side wall redesign, that also saves more than 500grams. Sailing weight is calculated to be max 250kg.