Small Boat Designs - 10' to 30'
Tad Roberts Yacht Design

Designer's Comments

Updated 2013/01/02: New construction blog, Benjamin Lester's Building Ratty .

Ratty is based on the Drascombe designs of John Watkinson; the best known is the Lugger introduced in 1963. I have always admired the simple traditional good looks of these boats, but I have had a number of thoughts on how to improve them--with increased beam, flattened and more powerful sections, and a more efficient, simpler rig.

Ratty was first put on paper as one of a group of designs for a WoodenBoat article on sailing cruiser design. For a family or 3-4 adults, she is a spacious daysailor or a camping cruiser meant for use alongshore. Under sail, oars, or a small outboard, my family will use uses her for daysailing and weekending in the Gulf of Georgia and the Gulf Islands. Ratty is safe and comfortable for beginning sailors and has rewarding performance for experienced ones.

The rig is a standing lug cat-ketch. Spars are unstayed hollow box section Sitka spruce. Total sail area is 174 square feet, with 122 in the main and 52 in the mizzen. The unstayed cat-ketch has several advantages over the standard Drascombe ketch. As Ratty has no jib, there is no need for shrouds to maintain forestay tension. No stays or chainplates simplifies construction and aids movement aboard Ratty. Her spars are short and fit inside the boat: Mainmast length is 18' and I can step it alone with the boat afloat. The lug sails provide a low but powerful sailplan, and a lower center of effort means less heel while sailing.

Ratty is 20' overall and 17'6" on her designed waterline. Beam is 6' 8" and draft with the centerboard up is 12". Board down draft is 4'. Her trailering weight is 600 lbs. with a 130 lb steel centerboard but no ballast. If sailed with a small crew of one or two people she should have 300-400 lbs of ballast installed under the floorboards. She is designed to sail at a weight of about 1300 lbs.

Ratty is also equipped with a small outboard well into which can be fitted a 4 HP gas outboard. For aesthetic reasons it was important to me to keep the transom intact and clear of add-ons.

Beam, especially waterline beam, translates into speed under sail. Beam also provides buoyancy that counters the heeling force of the rig. So power from the sails is translated into forward acceleration instead of heeling. Ratty's flatter sections mean more beam at the waterline, thus greater stability, so she can stand up to her sail and will be faster than the traditional Drascombes. The increased stability also means she can carry more sail in higher winds.

Ratty's construction is 3/8" mahogany plywood planking over an internal structure of half-inch plywood bulkheads and longitudinal plywood tanks. All joints are epoxy fillets and the entire boat is sheathed with 2oz fiberglass set in West System epoxy resin. All structural members, keel, stem, apron, knees, etc, are laminated Douglas Fir. Longitudinal cleats, floorboards, and thwarts are red cedar. Her rails, breasthook, quarter knees, and main mast partners are purpleheart, from Central America. Her low maintenance polyurethane painted finish contrasts nicely with the fine joinery and gloss varnish used on the interior components

The boat was built on Gabriola Island, B.C. by Richard Lyons and Quill Goldman of Barefoot Wooden Boats; the spars were made by Trevor Henderson. Construction took about three and a half months and she was launched on April 29 2002.