A sketch of the original proa design using a windsurfer sail, with child in flying outrigger hull.
Jim's home | Trimaran home | Canoe conversion home
10/13/2004 - I've been building this car-toppable trimaran using a 17' aluminum Gruman canoe since last spring. Early incarnations involved using a plastic kayak as an outrigger to make a proa, but in the interest of stability I changed the design to a trimaran. The outer hulls are of "stitch and glue" construction using thin plywood with epoxy/fiberglass at the seams to reinforce and protect them.
A sketch of the original proa design using a windsurfer sail, with child in flying outrigger hull.
View from above.
And the side. The hulls are stitch and glue mahagony plywood with fiberglass on the seams.
Me included for scale.
Sitting on the crossbar seat. Max and Evan will ride here, or a heavy adult on a windy day.
The seat at the end of the crossbar.
A close-up of the retractable leeboards. Both leeboards are made of laminated marine plywood coated in fiberglass and epoxy.
The junction between the crossbar and the amas.
A detail of the crossbar-ama junction. Clevis pins shown.
Crossbar attachment to the canoe gunwale. Clevis pins again. One side has a hinged arm for removal, the other side is fixed.
Strut used for the base of the mast. Uses a windsurf mast foot.
Back end of ama showing drain made from 2-liter pop bottle nozzle. Also used with water rockets.