Rowing a boat takes more than just grabbing a pair of oars. Fitting oars of the proper size and weight to a boat means experimenting with blade area, weight and flexibility. Specific boats need specific oars.
That’s why this oar design is universal. It’s for the amateur woodworker, but the plans can be adjusted to change the length (from 5 feet to 10 feet), the weight (based on the wood type) and the blade design. Before you begin, however, figure out the kind of oar you need to maximize the speed and maneuverability of your boat. Faster, lighter boats require longer, lighter oars, while heavier boats need shorter, more rigid oars.
You can simplify construction and material selection by laminating and shaping the shaft separately and adding the plywood blades afterward. This lets you interchange a variety of blade sizes and shapes on the shaft, depending on conditions. Blades can easily be repaired or replaced after hard wear. To remove and replace a blade, simply cut off the edges, trim with a block plane and glue a new blade onto the shaft. By using epoxy no screws or nails are necessary.
1. Start with the shaft
The shaft is built up by laminating a pair of ¾- or 1-inch-thick boards together with epoxy. The glue line between the two boards will serve as a handy reference point when shaping the shaft. Two ¾-inch boards are sufficient for lightweight oars of 8 feet or less-longer oars might require slightly thicker pieces of wood.
2. Cut the shaft
Using a straightedge, draw the centerline of the shaft. Measure out from the centerline on either side to your desired width (usually about 2 inches total) and draw the shaft outline. Use a ballpoint pen for clarity. Now, carefully cut just outside the line with a band saw or jigsaw. Once the shaft is cut, trim to the line with a block plane.
[pagebreak] 3. Make it balance
Balance is important when fitting oars. Some builders prefer to leave the shaft square above the oarlocks to provide somewhat better balance. (Note: Oars need to be slightly heavier outboard for easier rowing.) However, octagon shapes are particularly attractive for hand-built oars, and the shape is achieved easily with a hand plane. To do this, plane a flat across each corner after the shaft is trimmed square. This produces an octagon shape; it should taper to the blade end of the shaft. Woodworkers with more time can create a round shaft by shaving a small amount off of each corner of the octagon to create 16 sides. With coarse sandpaper, sand and smooth the sides until the shaft is round.
4. Shape the ends
After shaping the shaft, use a block plane to cut a flat surface on one side of the blade end. This will serve as the glue surface on which to attach the plywood blade. Use a coarse rasp on the other end to shape a relaxed but secure hand grip.
5. Blade building
The plywood blades should be rough-cut to shape, typically 24 inches by 8 inches. Round the corners, first with a hand plane and then by sanding with coarse sandpaper until the blade reaches your desired shape. Apply epoxy to the shaft and blade and attach the blade to the flat mating surface on the shaft. Clamp the two pieces together until the epoxy cures. If you are unsure about the optimal blade shape, cut the blade slightly larger than necessary and trim it after tryouts.
6. Oar protection
Seal the oar with epoxy, which will make it more durable and prevent water soak. Oars take a lot of punishment, especially on rocky shores, so pay particular attention to the plywood blade edges. Once the epoxy dries, put a top coat of varnish on the oars.
7. Oarlock Options
There are several commercial products and traditional methods for protecting oars at the points where they make contact with the oarlocks. These include plastic shrink wraps, leatherr sheathing and wrapped twine. The twine, after it is wrapped, can be covered in epoxy or varnish. Even duct tape will work. Don’t use brads or tacks to hold the oarlock wrap in place because they open holes in wood that make the oar susceptible to rot.
For more information on this project, visit www.butlerprojects.com or email paul@butlerprojects.com