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This report first appeared in the smalltrimarans.com blog
BUILDING A STRIKE 16 TRIMARAN
by Dave Shatwell
Not long after I moved to Lima ten years ago, I said to my wife Giuliana, ‘why don’t we build a catamaran?’ Giuliana thought that was a good idea, and I started to look on the web for plans. At that stage our building space limited us to a 14 foot boat, and the most suitable design of that size was a Pixie, by Richard Woods. The Pixie is a simple stitch-and-glue plywood boat, using a deck jig to induce compound curves. I had built a few dory-type catamarans in the past, and I wanted to try this technique. The other advantage of the Pixie is that the cross-beams slot into boxes in the hulls, and it is held together by the trampoline and the tension of the rig. This was important because here, a trailer or its load can’t be wider than the car that is towing it, so the boat had to be easily dismantled.
This is the start of building the Pixie catamaran that became the Strike 16 outriggers
Materials and fittings for the boat were a challenge. Fiberglass, epoxy, filler and good quality oregon timber are available, but there is no 4 mm marine ply. The best plywood is called lupuna, so that is what I used along with 2 or 3 coats of epoxy and also fiberglass tape along the keel and sheers. I imported the mast and its fittings from the Dwyer Mast Co in Maine, with considerable customs hassle in Lima. At the time I was mostly working in Argentina, and in Buenos Aires I ordered a mainsail, jib, and trampoline from the local branch of Hood sails. Other hardware was brought from Miami or Sydney by friends and family members.
We joined the Club de Regatas in Lima and sailed the Pixie for the next few years. More importantly, it was the entry into sailing for us as a family. Our son David, now 17, became involved with Sunfish dinghy sailing, and represented Peru in the World series in 2013 and 2014. Giuliana was also active in the Sunfish scene as coordinator and recreational sailor. So indirectly it has been a great catalyst for other activities.
Early construction of the Strike main hull
Meanwhile, Richard Woods had produced designs for two small trimarans, the Strike 16 and 18, using catamaran hulls as outriggers. We had moved, and we no longer had our building space, but we owned a lock-up space in a commercial center a few km from our apartment. I figured that it would be big enough (just) to build a 16 foot boat and get it out through the door.
Why a trimaran? We loved the catamaran, but both Giuliana and I have back problems and we wanted a boat which we could sit in rather than sit on, and maybe sail a bit further afield. But also, I had owned boats with one and two hulls, but never three, and I needed a new project. I had the idea that I could have a kind of convertible boat but in the end there were irreversible changes to the Pixie hulls, so its days as a catamaran were over.
Main hull complete
The recommended rig for the Strike 16 is that of another Woods catamaran design, the Quattro 14, which is basically a racier version of the Pixie. Quattro sail area is 13.1 square meters, whereas the Pixie has 11.5 square meters. I wanted to use the Pixie mast and rig, but I thought it would need a bit more sail area, and Richard suggested a new and larger genoa. I drew up a genoa which increased the total area to about 13 square meters. On a trip to Sydney, North Sails made this and also a pair of new trampoline halves to replace the original ones, which by now had been repaired once too often. Another modification was the addition of small skegs to the outriggers, which incidentally improved its performance while still in catamaran mode. The cross-arms are 3-inch aluminum tubes supplied by Online Metals which Giuliana carried in her luggage on a trip to Miami.
On trailer, launch day
The plans for the Strike 16 are quite detailed and easy to follow, but since a number of different 14 foot beach cats can be used as outriggers, some details are left up to the builder to determine. It´s important to ensure the beam boxes are in exactly the right position and square to the hull, since any errors of alignment will be increased at the outboard ends where they bolt onto the outriggers. I was worried that in spite of my best efforts it would not go together properly, but with just a small amount of encouragement, everything lined up.
The Pixie hulls hadn’t deteriorated over the years, in spite of being kept outside under a cover, so I was confident about using the same exterior ply for the trimaran. However, I decided to sheathe all exposed plywood in 6 ounce fiberglass, which added quite a bit of work and expense, and (more importantly) some weight penalty.
The Club Regatas has no launching ramp, and boats are either launched off the beach (and into a mild surf) or off the wharf by crane. Since our trailer isn’t galvanized, I opted for the crane, which is free. On our first sail, there was only a light wind, but the boat moved along well, was very light on the helm, and tacked without drama. Ten-year-old Fernanda, who is an Optimist sailor, took the helm without any difficulty.
Where we sail, there is no bay as such but there is an area of moderately sheltered ocean protected by a headland to the south, another one at La Punta about 10 miles north, and an offshore island. In this area, the wind is normally less than 10 knots from the SW, which is ideal for reaching up and down the coast. The Strike will easily carry two or three of us in reasonable comfort and performs well in all conditions that we have experienced, (winds up to about 12 knots with some ocean swell) and steering is very light and responsive. In stronger winds, some spray comes aboard and stays there, but I have never felt the need for a cockpit drain. We use a 2 h.p. outboard as an auxiliary and for maneuvering up to the dock.
An unusual feature of the Strike is that the mast sits on top of a small windscreen, with the load carried by a king-post. This arrangement elevates the rig so the boom is above head height. Combined with a bulkhead, the windscreen provides a small, dry storage space, but can be an obstacle in accessing the foredeck. A furling headsail would largely eliminate this problem. There is more dry storage under the foredeck, although a bit difficult to reach.
In Lima boats are bought, not made, and only a crazy gringo would build his own, so our Strike is the only trimaran (apart from a couple of Hobie kayak-trimaran hibrids) and the only home-made sailing boat of any kind at the Club de Regatas. Boat-building is a relaxing activity, at least for me, and a great satisfaction to see the boat take shape. At various times during the building process, I asked Richard Woods for advice and it was always forthcoming, either through his forum or by direct email. I have made mistakes in the construction process, but epoxy is forgiving and I have avoided major errors through Richard’s advice.
The Strike 16 is an excellent design, well within the capability of a person with normal woodworking skills to build. How long did it take? Too long, but it was always a work in progress along with work, sailing and family life.