Written by Walt Collins
Help For Classic Moth Builders And Designers
- Achieve a hull weight between 75 and 80 pounds.
- This is fairly easy to accomplish in any one of 4 basic constructions.
- 1/8 inch plywood covered in epoxy/polyester glass
- 1/4 inch light weight (LUAN) plywood (no glass)
- Molded fiberglass (3-5 plys of 10 oz cloth)
- Fiberglass/foam sandwich
Choose a construction that is compatible with your building skills and hull shape Both the 1/4 and 1/8 ply constructions will require a light, but strong frame system. My favorite is the 1/8 inch ply with EPOXY glass cover, using a monocoque frame, and built over a jig. This will usually result in a minimum weight. Stiff, and strong hull. If the boat is to be stored outdoors, either fiberglass or the sandwich becomes the preferred.
- Math the hull shape to the skipper's size and skill.
- Narrow deep hulls are quick upwind and carry heavier skippers well, but are difficult to control downwind, especially in a following sea.
- Lighter skippers need a beam near the maximum for upwind work in moderate to heavy air.
- "V" shaped hulls handle chop well, but do not plane as soon as a flatter section.
- Ensure adequate distance between the boom and cockpit floor for older skippers. The easiest ways to increase the clearance without sacrificing sail area is include generous crown in the foredeck at the mast or add depth to the hull throughout.
- Remember that most successful Moth designs have been compromises. Think, plan, then build.
- Moths are SAILBOATS. No matter how good the hull design, or skilled the skipper, a poorly shaped sail or one that does not fit the spars correctly, will sabotage the entire effort. I recommend purchase of Moth sails only from sail makers experienced with classic moths who are aware of the skippers size, and the relative stiffness of the spars which will be used.
- If you don't want to worry about any of the above, come to some of our races and see which of the different designs work best for the people who are the most like you. Then, build or buy a similar boat.