A Simple Light Weight Sliding Bow Seat
Here is a simple sliding bow seat that adds very little overall weight to the canoe. I’ve used variations of it on three of the last four canoes I’ve built, and it has proven to be easy to adjust and rugged. With rails about 36” long and a seat about 10” front to back, this arrangement will provide about 20” of fore and aft adjustment. The basic components are: 1) rails for the seat to slide on; 2) thwart to support the aft end of the rails; 3) the seat; 4) straps to fasten the seat to the rails; 5) a jamming cord to lock the seat in place.
Fig. 1 shows the overall layout and provides dimensions for the components. The dimensions are approximate, but if built as shown it will easily support a 250# bow paddler.
All the pieces should be made up and fitted before epoxying the support blocks to the hull, since dimensions of the rails and thwart will determine position of the blocks. I typically put the top of the seat about 9 ½ “ above the bottom of the boat. Dimensions of the thwart and rails will determine final position of the support blocks, but remember the aft blocks must be lower than the bow blocks by the thickness of the thwart. The position of the forward support blocks will determine the spacing between the rails. Minimum spacing should be about 16”, but ultimately the dimensions must suit the bow paddler.
Tops of the support blocks may need to be sanded or cut to the proper angle so the thwart and the rails lie flat across the blocks. Once the placement is determined and the tops of the blocks have been adjusted to fit the thwart and rails, you can epoxy the blocks to the hull. Before gluing, rough up the hull with a little with sand paper and put masking tape around the block position so you know exactly where to place it. This also makes clean up a little easier. You can remove the tape once the epoxy has started to set up a little. It’s also a good idea to clamp the forward and aft blocks together with a length wood (a section of cedar strip will do) so they stay properly aligned with each other. Use epoxy thickened with wood flour to attach support blocks to the hull. While the epoxy cures, you can clamp the blocks to the hull using a length of cedar strip that will land on both the inwale and the block. Use a large spring clamp to hold the cedar strip in place. That will put enough pressure on the block to hold it against the hull. See sketch #1.
When the epoxy has cured enough to remove the clamps, I like to bond a small piece of fiberglass cloth across the top of the blocks and a few inches up the side of the hull. This may not be necessary, but gives me peace of mind and will provide a bit more strength. I once mounted a block in the wrong position. By the time I found out, I needed a chisel and rotary sander to remove it. It convinced me of the bonding strength of epoxy.
With the support block in place you can refit the thwart and rails, and screw them in place. A single # 8 or #10 by 1 ½” - 2” in each end will hold them to the support blocks. I like to fasten the rails to the thwart with a #8 or # 10 machine screw with a pal nut and washer on the bottom side. Before you fasten the rails to the thwart, make sure they are parallel with each other and aligned with the centerline of the canoe.
Cut the seat to width. The seat width should be the same dimension as the outside to outside spacing of the rails, or just a little longer. You can route or carve out the bottom of the seat frame about 1/8” deep at the points where it will rest on the rails (see figure 2), but that is not absolutely necessary.
Make up the straps from 1” webbing (see figure 3). Length depends on the dimensions of your rails. Mine are typically about 6 ½” to 7” long. Set a 1/8” brass grommet about 5/8” from one end. Fit that end of the strap to the under side of the seat frame as shown in the sketch below and fasten with a #8 by 5/8” SS pan head wood screw. If positioned properly, the strap should be held right against the rail. Wrap the strap around the rail. Locate a second grommet about ½” to ¾” in from the edge of the seat frame. It should not be directly over the bottom screw (see figure #4). Once the second grommet is set, you can remove the strap and use it as a pattern for the other three. You need to make one strap for each corner of the seat frame. A third grommet should be located about half way between the two end grommets on each strap. The jamming cord will later lace through this third grommet.
When all the straps are made up, fit them to the seat frame just like you did the first strap, fastening first to the bottom of the seat, snugly against the rail. This is a key point, as the bottom screw and grommet help to keep the seat aligned with the rail. The straps should not wrap too tightly around the rail. The seat should be able to slide easily. See Sketch #2 for how these parts fit together.
Now tie a lightweight line to one of the middle grommets (see figure #5). Run the line through a small spring clip (the kind you would use to tighten up the chin strap on your hat), through the other middle grommet and back through the spring clip. Tie a loop in the end of the line. Put the seat in the position you wish. To clamp the seat tightly to the rails, just relieve the pressure on the spring clip, pull the line tight and release the spring clip. This should pull the straps sideways, and hold the seat tightly to the rail.
Just for reference, the seats I use are obtained from Western Canoe and Kayak in Abbotsford, BC. These are light strong and relatively inexpensive. They typically sell them as sets of one bow and one stern seat. The bow seat is about 5” to 6” wider than the stern seat, and would not work well for this project, so I purchase two stern seats instead.
Attachment: Bow Seat Collage, 3.JPG (Downloaded 45 times)
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