Carving a half-model

Half-model of the cutter Madge

In the early 1850s, at the peak of the age of sailing ships, Donald McKay designed and built a series of ships with names like Stag Hound, Flying Fish and Sovereign of the Seas. Over the span of five years McKay’s East Boston shipyard built 18 ships, each pushing the outer limits of ship construction and the design of the most complex machines ever conceived and realized by man: the “extreme” clipper ship. The opening of the Pacific Ocean and the frantic greed to get from New York City to San Francisco’s Gold Rush of 1849 made the sheer speed of the clippers more valuable than mere bragging rights, as one record after another were smashed by McKay’s thoroughbreds, cutting the time from the east coast of America to the west to three months. So valuable were McKay’s designs — the source code for the innovations that turned centuries of naval architecture obsolete in an instant — that he burned the wooden half-hull models in his office woodstove.

Carved half-hull scale models were used in lieu of blueprints for centuries. They were physical representations of what a new design would look like, a model for the customer to handle and inspect, and a vital source of the various measurements and shapes the shipwrights needed to build a full scale version.

The New York Yacht Club’s Model Room with half-models of past member’s yachts.

Some of the models had slots cut into them so a piece of card stock could be inserted into a slot and a pencil then run along the curve of the hull to give the shipwrights a template for that section of the hull’s shape. “Lofting” is the process of expanding the lines of a two-foot long model into a 150-foot ship, and was done in an open sail loft with room to work out the lines and create full-sized patterns of the ship’s ribs.

As yachting became a popular pastime after the Civil War, designers would often present the model mounted on a backboard to the customer, something for the wall of his office or yacht club club house to show off his excellent taste and inspire some mid-winter reveries of summer sailing.

In the early 1970s my father commissioned a half-hull model of his Wianno Senior from Malcolm M. Crosby in Osterville, one of the famed Crosby family known for their Cape Cod Catboats, the Crosby Striper, as well as the Wianno Senior, Wianno Junior, and a lot of other small boats, skiffs and yachts popular with the local fishermen and yachtsmen. It was a simple model, painted in the colors of the Snafu III with a yellow hull and a green bottom. A year later my father commissioned Malcolm to build a half-model of a Cotuit Skiff, the 14-foot flatiron skiffs raced by the Cotuit Mosquito Yacht Club. That model was also painted the Churbuck family colors of a yellow hull, but include the green boottop (the narrow stripe that run along the waterline) and white bottom. Eventually I changed the Wianno Senior’s colors to match the skiff’s — painting a green boottop and committing myself to a white bottom, which after a few weeks in Cotuit Bay, would turn brown with slime and required a lot of snorkle diving to keep clean.

The Cotuit Skiff half-model carved by Crosby was mounted on a big wooden backboard above a brass plaque engraved as the Henry Chatfield Churbuck Trophy, awarded annually to the CMYC racer who won the Senior Series — the Friday afternoon races open to sailors younger than 25 years old. Naturally my father created the trophy the year I won the series, so my name was the first to be engraved on the thing. A few years ago Larry Odence, author historian of a beautiful history of the Cotuit Skiff, organized a trophy case at the Cotuit Library to display the yacht club’s permanent trophies and spare them the dings and scrapes that occur when the winners took them home for the winter, hanging them in dorm rooms or who knows where. I had the trophy refurbished and remounted on a walnut backboard and all the names of the winners over forty years were re-engraved on a silver plate.

I’ve used these days of pandemic isolation as an opportunity to teach myself boatbuilding, paying close attention to the rudiments of the craft and starting modestly, building four sawhorses to begin with, and gradually working up through a few full ship models to an actual boat: the “Ruth” wherry I built over the summer of 2020 with my daughter and son-in-law. With that boat finished in early August, I turned my attention to building a new workshop in the old two-bay corrugated tin garage to spare my suffering wife from the pungent fumes of solvents, epoxies, paints and varnish that wafted up from my grandfather’s boat shop into the sail loft and the bedroom adjoining it.

While there are online courses in ship design, I decided to teach myself how to read a set of boat plans, figure out the strange code of measurements known as offsets (represented as three numbers indicating feet-inches-eighths), and learn how to loft full sized patterns and templates from drawn plans. Having purchased the entire fifty year archive of WoodenBoat Magazine, I searched the back issues for relevant articles and found one about building half-models. The magazine offered half-model plans and kits for constructing them, so I ordered the plans for the 1879 cutter Madge, a “plank-on-edge” deep-keeled cutter designed by George L. Watson and built in Scotland for the thread tycoon, James Coats, Jr. The Madge was very successful in British yacht races, so Coats shipped the 46′ boat to New York aboard another ship, where she challenged and beat the fastest boats of the New York Yacht Club , impressing such early yachting writers as C.P. Kunhardt, a fan of the deep cutter hulls. But when the Madge went to Newport, Rhode Island she met her match in the Shadow, one of Nathaniel Herreshoff’s first yachts after an early career designing fast steam powered torpedo boats for the navy.

Discouraged by the decisive victory of the Shadow, Coats sold the Madge and she was hauled to Lake Ontario where she raced for a few years, before winding up abandoned in an empty lot outside of Rochester, New York.

Hulk of the Madge

The plans and instructions arrived in the mail and my next task was to find the right wood for the model. The method used in the Madge project is known as the “lift” or “bread and butter” method. The profile of the hull — the side view — is divided into 1/2 inch horizontal slices from the bottom of the heel to the uppermost edge of the deck — each slice of the pattern was represented by templates on the plans. I glued them to a stiff piece of poster board with spray adhesive and carefully cut them out along the inked lines, laying the template on top of the wooden “lifts” and tracing around the perimeter with a pencil to mark where I would cut them out on a bandsaw.

Finding the right wood is difficult — most local lumberyards don’t bother stocking any exotic woods, so I had to go online and order five foot planks of basswood, African mahogany, and red cedar. Those were not cheap, but eventually arrived in a big box. Because the lifts are 1/2″ thick, and the planks I ordered were 1 and 1/16th inch thick, I needed to “resaw” them to the required thickness on a table saw with a thin kerf resawing blade.

Soon I had a stack of identical 24″ long, 1/2″ thick pieces of mahogany and basswood, and a single 1/16th inch thick piece of western red cedar for the waterline. I coated the faces of the lifts with carpenter’s glue, tacked them together to keep them from sliding around with small brads, and then clamped the sandwich together with lots of clamps, letting it dry over night.

What resulted was a boat-like shape, but one with chunky steps, like a ziggurat or Minecraft character. Then the fun part began. Using a beautiful new 1/2″ wood chisel from Lie-Nielsen in Maine, followed by my low-angle “apron plane”, model maker’s plane, and brass spokeshave., I carved all the sharp corners off, reducing the “steps” between the lifts until the glue lines between them vanished.

Then followed more shaping and sanding, beginning with coarse 80-grit sandpaper on a sanding block and finishing with 220 grit by hand before the model was ready to be varnished.

I immediately made two big mistakes by rushing. The most blatant was my mis-ordering the stack of lifts so that the two topmost mahogany lifts that made up the hull and deck, were reversed. This required some delicate cutting away with a coping saw and careful fitting of the cut-off piece to the top lift. When I glued that to the model’s transom I left a cut mark that had to be filled with wood putty and sanded fair. It is a serious boo-boo visually. The second mistake I made was setting one of the brads used to keep the lifts from sliding out of alignment during the gluing/clamping process too far out from the back of the model, so that my sanding eventually exposed the shiny silver head of the tiny nail under the curve of the stern’s counter.

I kept pushing on, despite the flaws, because I was so pleased with the final shape and how it fit the six side-view templates I took from the plans. I finished the model “bright” (clear varnish vs. opaque paint) with three coats of TotalBoat varnish sealer, followed by eight boats of Epifanes varnish — each coat was sanded with 400/600/800 grit wet sandpaper then cleaned with a tack rag and a wipe of a rag soaked in rubbing alcohol. Each coat was given 24 hours to dry, then I sprayed the hull with soapy water and gently scuffed up the varnish with the wet paper, drying it off and holding the surface up the light to look for bright spots and circles, an indication that another coat was needed until all those shiny depressions vanished and the hull was immaculately sealed in a thick shell of six layers of varnish, gleaming like a candy apple.

My cousin Pete let me pick through his wood shop’s offcut pile, and gave me a gorgeous 10″ wide plank of hardened eastern white pine. I cut that down to size, routed a clean edge around the perimeter (routers are insane tools which my father told me were finger-eaters, hence neither he, his father, or I wear any rings, including wedding rings, for a bandsaw blade or planer that catches a ring will strip it and all the flesh from it to the tip off the finger leaving behind bare bone ((or so I was told))).

I’m pleased with the result and now I feel confident to now move on to making half-models of boats that are relevant to me and the family history — two Cotuit Skiff are next, followed by a three-masted coastal schooner like the Joseph Eaton, Jr. my great-great grandfather’s coastal schooner and tthen maybe a Mattapoisset whaling bark like his ship the Massachusetts. I’m looking forward to making more small boat models and indulging my college education in 19th century American maritime history with a New Haven Sharpie, Cape Cod Catboat, Whitehall gig, Swampscott dory and so on.

And finally, I’d like to thank Betsy Crosby Thompson and her father, Malcolm M. Crosby, for their excellent series of videos on YouTube. I learned a huge amount from them, and wouldn’t have achieved the result I did without Malcolm’s wisdom. I also picked up some great tips such as how to properly fold a piece of sandpaper, how to wet sand, and how to use a spokeshave.

Author: David Churbuck

Cape Codder with an itch to write

3 thoughts on “Carving a half-model”

    1. Yep, sophomore year I wrote a big paper on the New Haven Sharpie for William Ferris’ American Folklore class. Best thing I ever handed in.

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