'ekolu pictures

'Ekolu - a Plywood Sailing Canoe

by Matthew McGranaghan


(Thanks to Rebecca Goodman for taking these photographs.)

This is 'ekolu, a 16-foot, car-toppable, plywood sailing canoe.

The canoe is a slight modification of James Wharram's "Melanesia" design. (See the Wharram web-site). As evidence that Wharram's plans allow nearly anyone to build a boat, 'ekolu was built in the ante-room of my office over the course of about a month during the summer of 2000. The biggest modification was to make the canoe symmetrical fore and aft, in anticipation of sailing it as a shunting proa. As it turned out, the rig that was at hand was not suitable for shunting and 'ekolu is sailed as a tacking canoe. The additional fullness in Wharram's stern section would probably be a benefit. The use of an American Canoe Association 44 sq. ft. "Cruiser Class" lateen sail, and the addition of gunnel rail trim were other liberties taken with Wharram's design.

The hull is 1/4" marine plywood, stitch-and-glue construction. Using Wharram's bow shape, both fore and aft, halved the number of panel shapes in the hull, reducing both layout and sawing time. The eight main panels came from only two shapes to sabersaw from a stack of four strips of plywood. The panels were stitched together with copper wire and the shape trued before the seams were "welded" with thickened epoxy. Fiberglass tape reinforces the seams, both inside and out. Backing plates at the lashing points support the thin plywood against the lashings. The rail trim is 1 1/2" x 1/2" red mahogany inside and out. This gives a slightly wider place to sit, and stiffens the hull considerably, but adds weight.

The original ama was a scrap 10' 4"x4", which was salvaged from a construction site. Its slight shaping is visible in the photos. The bow was pointed by machete and then a little work with a Stanley Surform (tm) rasp. The stern was rounded slightly with the rasp. The stanchions are 2' pieces of 3/4" dowel. They are pressed into sockets bored into the 4x4, and lock into it due to their angles and the loading. The 'iakos are found bamboo and other poles.

The ACA Cruiser rig is extremely simple and works well enough, though more than its 44 square feet could be handled easily. The mast, spar and boom are all T-6061 aluminum tubing, 1 1/2 inch for spar and boom, and 2 inch for the mast. The halyard is clove-hitched to the spar, run through an eye in the end-cap (from a Laser) at the mast head, and, in use, is tied-off to the mast below the partner. A snouter loop holds the boom close to the mast. The sheet is clove-hitched to the boom, and handled directly. Neither hitch has slipped in service.

Setup takes only a few minutes. Four lashings secure the 'iakos to the stanchions on the ama, and four more lashings secure the 'iakos to the hull. The mast steps through the partner (which is usually left lashed to the hull) and into a socket epoxied to the floor. Setup in the right orientation to wind and water, the canoe practically pulls itself off of the beach.

On the second trials day, I forgot to take the steering paddle to the beach. This turned out to be alright. The canoe steers well with just the sheet and fore and aft trim. Bow down, she heads up, and bow up, she falls off. The unstayed mast allows the sail to be well forward of normal operating ranges, facilitating some interesting points of sail.

The drag of the ama makes tacking challenging. The hull tacks around the ama very well, but levering the ama around the hull is more difficult. Several times I ended up in irons, and backing down proved the most expedient way out.

Half of the time, a tacking canoe is trying to bury the ama. Needless to say the resulting drag can impede progress. Experimentation showed that easing the sheet relieved stress and moved 'ekolu along at least as well.

An 8' long plywood ama has been built to replace the 4x4, and has been sailed a little. It is 8" wide and flat-bottomed, with lots of rocker. The sides and the bottom are sections of arcs 4" deep on the 8'. The new ama has greater buoyancy and tends to skip lightly over chop. With it, the canoe tracks less well but tacks more reliably.

Last modified: 3 August 2006