The Flatfish plan specifies either white oak or mahogany for the transom. I chose mahogany because of its classic look. The transom thickness is 1 1/8″, so I needed to purchase 5/4″ thickness planks from which I could mill and then glue up boards to produce a blank that was roughly 4′ x 5′ in size. I got my planks from Highland Hardwoods in Brentwood, NH.
There are a variety of woods commonly known as mahogany. Two general categories are “Honduras” and “African.” Honduras mahogany is also known as “genuine mahogany;” the so-called African mahoganies are actually different species. Both actually look quite similar, and Justine incorporates both types. To my eye, the main difference is that Hondouras has a more even color, and African tends to have more pronounced lighter and darker bands parallel to the “grain” of the wood. In spite of its “more even” color, Honduras mahogany can have very distinctive grain patterns, as seen below.
My transom planks were about 7″ wide at most, so the transom needed to be made up of 7 planks, glued edge-to-edge. Large glued-up members like this are more likely to resist splitting and warping if the joints are reinforced by embedding metal rods called “drifts” as the boards are being glued up. I used 10 pieces of 5/16″ bronze rod, about 8″ long, driven into predrilled holes that crossed the joints and spanned the planks on both sides of the joints. The holes need to be drilled very carefully so they don’t wander away from the center of the planks, and the drifts need to be placed with forethought so that they will not interfere with any fasteners that go into the transom later in the construction. The planks were glued up using West System epoxy.
I smoothed the glued-up transom using a hand plane, followed up by hand sanding. After sanding I applied a coat of shellac to seal the wood and give it some protection from stains.
A piece of the backbone known as the transom knee is bolted through both the transom and the keel plank to span and thus reinforce that joint. My transom knee was made from a piece of white oak.
Nearly all of the fasteners that join the backbone members are silicon bronze carriage bolts, ranging from 1/4″ to 1/2″ in diameter. Carriage bolts have a smooth rounded head, and the upper part of the shank, just under the head, has a square cross section. The other end is threaded, and secured with a washer, lock washer, and nut. As the nut is tightened, the square part gets drawn down into the fastener’s (round) hole, preventing the head from turning. In this way the bolt can be fully tightened from one end, without needing a tool to hold the other end. The head of the bolt can be buried below the surface of the wood, and if the bolt becomes loose, it can be retightened simply by tightening the nut.
I wanted to carve my boat’s name in the transom and realized that I should do that before securing the transom to the construction molds. This would allow me to do the carving with the transom horizontal, and at a convenient working height.
Justine is named after Justine Liff, who we met while she was Boston’s Parks Commissioner. We quickly became friends with Justine and her family. Sadly, we only knew her for a short time before she became very ill with cancer and died. My wife Annie, an Episcopal priest, presided at her funeral at Boston’s Franklin Park. During the funeral, Boston’s Mayor Tom Menino told the assembled crowd that Justine’s assistant said that she didn’t have to blow-dry her hair, she could just follow Justine around for 15 minutes and the breeze that was created would suffice. This was a good omen for Justine the boat!
Once Justine is in the water, the transom will be tilted at about 45 degrees to any viewer. I factored this into my layout by stretching my letters by about 40% in the vertical direction. After picking out a font and laying out the stretched letters on a slight arc to complement the shape of the transom, I made a prototype carving on a piece of basswood.
After carving my prototype, I made very small adjustments to the letter spacing, then proceeded to transfer the layout directly on the transom. I did the transfer by blackening the reverse of my layout drawing with a soft pencil, then laying it on the transom and tracing over the letters. This gave outlines of each letter on the wood that I could carve from.
With the frames, stem, and transom in place, only the keel plank remains for the backbone to be complete.