The catboat is a beamy, monohulled sailboat descended from a line of working watercraft. No one is sure of the origin of the name “catboat.” Some said the boat was as fleet as a cat. Or, the name might have been inspired by dock cats that greeted returning fishermen. Catboats fished, hauled freight, and ferried passengers along the U.S. Eastern Seaboard as early as 1850. Their spiritual home is Cape Cod, Massachusetts, where generations of the Crosby family built catboats, determining their shapes with hand-carved models.
The beam of a catboat is typically half its length. Such generous beam afforded room for a fisherman to work. A single mast, stepped far forward, has a forestay but generally no shrouds. The rig is a single sail, often a gaffer. Fishermen made headroom by furling the rig then hiking it high overhead with one of the halyards. Because catboats worked in shallow waters, most have shoal draft and a centerboard. Catboats have a characteristic barn-door rudder, hung proud of the stern and steered with a tiller.
Working watermen eventually adopted steam and gasoline. But a new kind of sailor, the pleasure boater, adopted the catboat, which retains a loyal following to this day.
Naval architect Charles W. Wittholz of Silver Spring, Maryland, designed boats ranging from 11’ dinghies to 85′ replica ships. In his career, Wittholz designed several catboats, but it was the 17-footer that he himself sailed on the Potomac River. Built in 1967, he named his boat GOOD OMEN and sailed her for more than 20 years.
The plans for the 17′ 1″ plywood catboat include 11 sheets with good construction detail: materials, dimensions, fastening schedules, notes, and comments. Several alternatives are included: self-bailer instead of deep cockpit, lead-ballasted full keel instead of a centerboard, open cockpit instead of a cabin, gaff or marconi sailing rig, optional anchor-handling bowsprit, and an optional inboard engine. The plans date to the early 1960s, so some of the suppliers mentioned have long been out of business.
The Wittholz 17 requires lofting from the plan’s offsets. Drawing the body plan (the end-on view) requires a 6′ x 10′ drawing surface and is critical to loft accurately as it provides the full-sized patterns for the frames. The 6′ x 6′ side-view lofting of the stem provides patterns for the stem/forefoot assembly. The lofting for this catboat is not complicated; Greg Rössel’s book, Building Small Boats, covers lofting nicely.
Hull construction is straightforward: assemble the oak stem, the 1/2″ plywood transom, and the nine frames of mahogany or oak with 1/2″ plywood gussets. Set those elements on a level building jig, upside down, with the frames 22″ apart. Fit the mahogany or fir sheer stringers and chines, and the mahogany keelson to the frames.
The hull sides and bottom are 3/8″ plywood. The plans suggest a layer of fiberglass cloth on the ply for extra durability. I know from personal experience that if you get the catboat sideways to the wind and ram the dock, you can crack some plywood along the sides. The most vulnerable areas are between the frames forward of amidships, aft of the forward bulkhead. I suggest adding oak blocking between frames about 12″ above the waterline and heavy-duty fiberglass-epoxy on the inside of the plywood in these areas.
In my experience, fir and Aquatek plywoods check and crack if painted only, so they must be covered on both sides with fiberglass cloth set in epoxy. If you do cover plywood in fiberglass, do it after cutting pieces to shape, before installation, while they are still flat. This is so much easier than fiberglassing an assembled boat. High-quality okoume plywood is nice stuff: no voids, many plies. Okoume, when used for parts of the boat other than the hull, benefits from a barrier coat of unthickened epoxy on both sides, but it does not require fiberglass cloth.
This boat will always have a little water in the deepest part of the bilge. Seal this area with several coats of epoxy resin.
Get the sides from 5′ x 20′ panels (two sheets 5′ x 10′ scarfed). Attach the sides first. Get the bottoms from 4′ x 20′ panels (4′ x 8′ sheets scarfed). The bottom panels overlap the side panels most of the way then transition to a butt seam forward. Fit the keel to the keelson before turning the hull over.
The sail plans include both marconi and gaff rigs. The gaff-rig mast I built is solid spruce: 5-1/4″ in diameter, 25′ long. The gaffer requires a single forestay but no shrouds. The hardware called out in the plans is all from Merriman Yacht Specialties, a company no longer in business. Most parts have readily available equivalents, but if gooseneck hardware is hard to find, try wooden jaws. See William Garden’s article, “The Right Jaws for your Gaff and Boom,” in WoodenBoat No.59.
The gaff rig’s solid mast is too heavy and awkward to step handling it solely from the foredeck. Lacking a crane, it requires a person on a low bridge or atop a neighboring houseboat to steady the mast while a crew of two lifts/lowers on deck. Spare halyards from two neighboring sloops would also work to step this mast.
Those wanting a trailer-sailer will look to the marconi rig then make modifications for folding. The builder will have to design the modifications, because the plans say nothing about folding. The marconi mast is a 5-1/4″ x 4-1/4″ hollow rectangle, 32′ 3″ long. This mast requires a forestay and two shrouds that belay aft of the mast partner.
The gaff rig peaks up higher than is usual for a center of effort similar to the marconi. Build either sail with two sets of reefpoints as shown on the plans. The second reefpoint has a calming effect in 40-knot winds.
The optional bowsprit is not for a jib, as a jib of any kind would unbalance the boat. The bowsprit is for anchor handling, equipped with a chock to guide the chain and rode.
The Wittholz catboat has a centerboard, as catboats commonly do. Draft with centerboard up is 21″, down 4′ 3″. The centerboard case is 6′ long, most of it in the cabin, with 19″ extending aft into the cockpit. The centerboard itself is 3/8″ galvanized steel. There are 500 lbs of movable ballast in the form of lead pigs under the cabin and cockpit floorboards.
The plans include an option for a full ballast keel, as seen in the catboat pictured here. The draft of the full-keel version is 28″. The builder must make a mold to pour 600 lbs of lead shaped to fair with the deadwood in the keel. The mold requires lofting, too; refer to the Bud McIntosh book, How to Build a Wooden Boat, for a simple explanation.
Either model weighs about 2,200 lbs, including the ballast. The trailer for it could be a bunkboard arrangement, but a trailer with boat stands is better. When trailering, the boat must rest on its keel, not its garboards.
The cockpit is seriously spacious. Sloop sailors often walk by and exclaim, “Look at all that room!” The cockpit can easily accommodate six people. The seats have a comfortable slope, and the coamings are tilted as backrests should be. The footwell is deep but not self-bailing. Water will sump to the deepest part of the bilge where a reliable pump awaits. For a self-bailing cockpit, see the plans; there is a sheet for that. The high sheer up forward keeps the cockpit dry in most conditions.
At anchor, it is a fine thing to hike up the sailing rig for standing headroom in the cockpit. On the gaffer, do this by furling the sail, lashing boom to gaff, and hauling on the peak halyard. For the marconi rig, modify the wire topping lift. Its upper end is fixed to the top of the mast, so modify the bottom end with 1/4″ rope, blocks, and a cleat on the boom to adjust it.
In the cabin, there is sitting headroom on berths port and starboard. The two lockers amidships are sure to be customized by the builder. At anchor, a Coleman stove works well in the cockpit aft, so the two-burner alcohol stove in the cabin shown in the plans may not be required. The drawings show a head up forward, but it flushes straight into the sea. Better find a place for a porta-potty, either forward or perhaps amidships port or starboard. When it comes to building the cabin, How to Build a Wooden Boat is again a good companion to the plans.
The plans show where to fit a small inboard engine, but a 5-hp, four-stroke, long-shaft outboard motor serves well as an auxiliary. The plans also show an option for stowing an outboard under a hatch set in the cockpit floor. On smooth water, the outboard will push the boat at 6 knots. Mount the outboard to a bracket on the transom, but keep it clear of the big rudder. Add framing in the transom for attaching the bracket to the boat. The bracket should be adjustable up and down to keep the propeller in the right amount of water, no matter where the passengers are. Most 5-hp outboards come with a propeller suitable for light craft or inflatable dinghies. For a boat of this size and weight, select a propeller with less pitch so that engine rpms are high enough to avoid lugging the engine.
In good conditions, expect this boat to sail to windward at 45 degrees off the wind. A sloop, with its two sails and narrower beam, might sail closer, but the catboat sailor specializes in his one mainsail and strives to get the most from it. The peak and throat halyards of the gaff rig provide control over sail shape. A three-part boom outhaul for either rig is useful to control the belly of the sail. The position of the crew greatly affects overall trim. Move crew aft or to windward to reduce weather helm, something catboats have in abundance. On this boat in particular, moving crew leeward can help push the hard chine underwater, so the side acts like a leeboard.
It is best not to oversheet a catboat. When hauled hard, the boom should be over the stern quarter of the boat. Hauled any harder, the boat slows down and crabs to leeward. Best to let out the sheet, find the wind, then adjust by looking for the sweet spot. On gusty days, do not cleat off the sheet; instead, wrap just enough turns around so it will slip when hit by a strong gust. On a reach, 15 knots of wind will move this boat at 6 knots. In stronger winds, reef the sail to match, preferably sooner than later.
At the helm, keep the tiller in one hand and the sheet in the other. One can sense immediately how the combination affects boat speed and trim.
This boat is built for comfort, not speed. What appeals most to me is how the Wittholz catboat provides so much space for its 17′ length. It’s a sailboat with berths for overnighting, and yet is buildable in a 20′-deep two-car garage. Over the years, I have come to appreciate its comfort, safety, good looks, and ease of sailing singlehanded. If I could add one thing to the plans? Fishing rod holders just aft of those stern cleats.
Monte Copeland grew up in a lumberyard along the Ohio River, but never connected wood with water until after moving to Austin, Texas. Now retired from computer programming, Monte and his wife Sheila sail on Lake Travis. In his shop is an old Shellback dinghy getting ready for new paint.
Wittholz Catboat Particulars
Load waterline/16′ 6.6″
Centerboarder draft, hull/21″
Centerboarder draft, board down/4′ 3″
Gaff sail area/220 sq ft
Plans for the Wittholz 17′ catboat are available in print and digital format from The WoodenBoat Store for $90.
Thanks to reader Dick Lafferty for suggesting we review the Wittholz catboat—Ed.
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