The Seaclipper 16 Open Cockpit folding trimaran is designed for amateur construction from mostly ¼″ (6mm) plywood with epoxy adhesives and coatings. It can be built in less than 6 months by an individual or as a family project.The plans are highly detailed and easy to follow with full-size patterns for many hull parts provided to facilitate the process. The mast and sails are scavenged from a Hobie 14 beach catamaran, which are inexpensive and available used or new. 

This boat can satisfy many different needs within a family. Its large cockpit and 11′ beam provide ample space for four people to sail comfortably, with compartments enough to stow the gear needed for family outings on lakes or along the coast. With a full crew, the 16 OC is a stable and lively daysailer—an ideal place for novices to learn sailing technique. Add a spinnaker and develop your skills further.

Sailed solo, the 16 OC is exciting to sail, given a steady breeze, speeds of 10 knots are likely. For intrepid sailors, the boat can be outfitted for short solo expeditions. It has plenty of compartments to stow provisions and extra gear. A small camping tent will fit over the cockpit and side deck. Add a side-mounted outboard (up to 4-hp) to provide auxiliary power.

A flat-wing folding system quickly reduces the beam from 11′ to under 8′ for legal trailering on the highway. The akas (crossbeams) are made from standard lumber materials, allows the boat to live on its trailer and be launched and ready to sail in less than an hour. One can even reduce the beam when afloat with the mast up, for instance in order to fit in a marina slip. Plans are included for building a custom trailer or for modifying a standard boat trailer to safely support all three hulls.

The Seaclipper 16 OC has two steering options: the standard tiller steering for conventional seating in the cockpit, and pedal steering to be used with sailing solo while seated on the cockpit floor. The rudder has a unique kick-up transom design with control lines leading to the cockpit. Weeds or debris on the rudder blade can be quickly cleared by pivoting the rudder up momentarily while sailing. The boat can be sailed onto the beach by releasing the rudder and pulling up the daggerboard. With the rudder and daggerboard partially up, one can explore the shallows to about 18″ of depth.

The Seaclipper 16 Open Cockpit is designed for sailing fun. Simple to build, easy to sail, on a very modest budget. Build a trailer from the plans, or buy one and build the bunks to support the boat. We encourage purchasing used outfitting gear; mast, sails, blocks and other fittings to reduce cost. Paint your boat a wild color and go sailing with your family soon.

Images of LIMONADA were taken by John Marples, Ben Breckenridge, and Mac McDevitt.


Length Overall 15′11″
Waterline Length 15′6″
Beam Overall 11′3″
Beam of Main Hull 2′5″
Draft, Hull Only 11″
Draft, Board Down 2′7″
Displacement, Full Load 800 lbs
Displacement, Dry 400 lbs
Payload 400 lbs
Sail Area, 100% fΔ 146 sq ft
Sail Area, Max 146 sq ft
Mast Length 26′6″
Bridge Clearance 27′
Engine Power 2-4 hp
Fuel Tankage N/A
Water Tankage N/A
Speed under Power N/A
Number of Crew 1 to 4
Berths, Min/Max N/A
Headroom in Cabin N/A
Design Fee to Build One Boat $180

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