The gunnels are one of the most important parts of the boat. They take abuse so they must be durable. They are the first thing people see so they must look good. And they give a lot of structural support so they must be strong. We’ll make the gunnels out of ash, mahogany, fir or oak. Each has an upside and a downside. Oak is heavy but strong. Fir is light but can have funny grain and be splintery to work with. Mahogany looks beautiful but is sometimes hard to get in straight grain in long lengths. Ash is usually your best option as it’s strong like oak, lighter, and not prone to splintering or fracturing. Your choice.
What you will need:
At least 8’ lengths of wood to scarf together to make 15-16’ lengths. 8’ x 1”x 8” boards should make one side of the boat, inwales and outwales.
Random orbital sander
80-220 grit sandpaper
3/4”-1 ¼” screws
Lots of clamps
Japanese pull saw with medium tooth blade
Make the raw gunnel stock 1 ¼” x ¾” x 8’ finished dimensions. Round over two corners on the long side as shown in the plans sheet 3. There should be eight of these pieces.
You will scarf the outwales and install them first. Make an eight to one scarf by beveling the bigger side of the wood. This is best done on the table saw but a power plane or jack plane will work. Scarf two pieces into one 15-16’ piece. Only scarf the outwales, the inwales will go in as two pieces. See drawings. Set them aside.
The inwales go in as two pieces because the oarlocks will be cut into them, no need to scarf. But you must shape the ends to fit into the transom. Find the bevels with your bevel gauge and cut the ends to fit the transom corners on both ends. Now mark the location of the oarlocks on the side panels. If you are putting in two oarlock locations, mark these two. The oarlock blocks themselves will be dovetailed into the inwale. Make the blocks to the dimensions shown on the plans. Clamp the blocks in place, the marks being the centers. Now fit the two inwale pieces in so that they fit nicely from the transom corners to the oarlocks blocks. You should be able to cut the oarlocks ends of the inwales at 30degrees to fit. Also make the small spacer in between the blocks at this time. When all the pieces are fit well, remove them, leaving marks for the oarlock blocks.
The outwales can go on, one side at a time first, unless you have enough clamps for both sides, and let them dry overnight. Glue them with slightly thickened epoxy. They can be screwed from the inside with 1” screws every 12”. Leave room for screws later through the outwales into the oarlock blocks.
Clean up the mess under the gunnels inside and out as well as you can to save sanding.
When both inwales are all cut and fit they are ready to go in. First place your oarlocks loosely with clamps. Then glue up the inwales with thickened epoxy and clamp them with as many clamps as you have. If you don’t have many, you will have to use a few clamps to hold the inwales in place, and then go along with two clamps to suck them up tight and screw them on from the inside. Make marks every 12” and move the two clamps down to each mark, suck them tight and tap up or down to get them flush with the top of the plywood. Pre-drill and screw the with 1 1/4” screws. When they are fit in tight from the transoms in, place the oarlock blocks in permanently with glue and screws through the outwale into the sides, avoiding the oarlock shaft hole. Lastly, glue the spacer in place.
Clean up your mess well.
After the inwales and outwales are in place, (This could take several days if you have just a few clamps.) clean up the epoxy which has squeezed out and sand the gunnels until they are smooth inside and out.
Now you will install the gunnels on the transoms. They will go in the same as the other except the inwale will be slightly larger to meet the side inwales better and the outwale will be slightly smaller. The outwale on the transom can either be fit in between the outwales on the sides or you can cut off the side pieces and run the ends outwale over it. Either way is fine. Clean them up well and sand them smooth.
Lastly, after all the gunnels’ are fit and sanded smooth to your satisfaction, flowcoat them thoroughly and sand them very smooth to 220 grit for varnish later.
At this time you can install the half round transom anchor plates. These are backing plates for the anchor pulleys. They are round shaped as shown in the plans with one flat side which will nest up under the gunnels on the transoms, inside and out. Place them in the center of the transoms and drill a 5/8” hole in the center of them as far up as it can be placed after they are glued on. You want the anchor line to exit as far as possible up the transom to allow for the anchor to clear the water. Sand and seal as always.
Next up: Guide seat!