Wednesday 24 July 2019

Alternate Seating for the Vuntut Solo Canoes


Over the past while I have been experimenting with various seating options for these boats seeking a solution that allows seat adjustment to balance the boat as it is loaded. At the same time to eliminate the draw back of Velcro seat attachments, their ability to come loose if the boat is dumped, this becomes more of an issue as the Velcro ages. This has involved finding a way to use a canoe seat in the boat while keeping the seat low to maintain the boats stability. Not being a small guy my experiments have been limited to the 14 as that is the boat that I have here at the shop presently that fits me, these ideas will directly transferable to the 12 and could be used with some modifications in the 10, if you need more info send us a note; getonthewater@sympatico.ca. Many of the seat pads that can be purchased are in the range of 50mm [2”] thick, after using the boat a number of times with various seat heights I settled on a height of about 90mm [3.5”]. This is the height used for both the seat with the end pads and the seat mounted on runners, this height was picked as good compromise of paddling height, comfort and stability.

The picture to the left shows a canoe seat with pads on the ends allowing the seat to be removed when not in use and spreading the load, otherwise the load would fall on the ends of the seat frame putting point loads on the hull. The draw back is that this does not eliminate the seat falling out if the boat is inverted whether inadvertently on the water or for carrying, secondly while this method does work it still puts a noticeable load on a small area of the hull also while it can be moved the fit changes as the seat changes position. If you plan on using a fixed seat position this is a good solution, I would do two things first; add an extra layer or two of glass an inch or two larger that the end pads to help distribute the load onto the hull, second; use the end pads in conjunction with the glass to help spread the load, the pad should be full as in the picture not individual pieces on the ends of each cross member. Glue the seat in place with thickened epoxy checking that it is level as you do so. To find the width of the seat required you can pick the width off the plans or from your molds, cut the seat about a ½” longer than required to allow some fine tuning of its fit in the boat. In the next option shown, the seat is trimmed to fit with the ends just beyond the runners.

The seat I am presently using has a pair of runners on which a canoe seat rests, the runners allow the seat to be adjusted depending on the gear that is loaded in the boat, they also spread the load over a larger area of the hull than the previously mentioned seat. Our runners are manufactured from cedar and result in a seat height of about 3.5” [90mm]. The seat is held down using brass large headed, quick connect bolts run through the seat frame into brass insert nuts set into the runners.

The most difficult part of making these runners is shaping the bottoms to match the changing curvature of boats where the runners will be placed, the exact position used is determined by the width of the seat you choose. If you are building the boat one way is to make patterns from the molds, measure out from the centre line and make a pattern as wide as the runner base, shape the runners using a block plane. Some of the initial shaping may also be done with a band or table saw, set the saw up to match the shallowest angle and cut with the blade just touching the edge that will remain. Even if using patterns mark and sand the area on the bottom of the boat where the runners will be located so that all fitting is done in the same location in the boat. During the fitting it is a good idea to sit the seat on top of the rails from time to time to ensure that the rails are not just level front to back but side to side and to each other, the seat also helps you check that the rails are parallel to each other.

The rails I installed are 24” [610mm] long and 3” [75mm] tall cut from standard big box store cedar 2x material, the measurements will vary depending on how far out from centre you place the rails, this will be dictated by the seat you choose, be aware of the seat height as it affects the boats stability, as your positioning in the boat is the largest factor in its location. The sides of the runners where tapered by running them through the table saw so the sides were sloped leaving a 1” [25mm] wide top, do this before you shape the bottom, so the piece is stable when you cut it.
Seat was placed with its aft edge about 4” [100mm] in front of the thwart, 93” [236cm] aft from the top of the stem, the boat sits level in the water with this positioning.

Once the rails are shaped to fit the boat and ready to install I rounded the ends and routered the edges, as can be seen in the pictures the rails are notched to take the ends of the seat, this will keep the seat from moving much even if lose a fastener or damage the insert nuts, leaving it at least serviceable until repairs can be made. As you can see there are five notches allowing for three seating positions, two seat positions would likely be enough but that is up to you, it would also save a bit of weight, the runners shown added about 3 pounds [2kg.] to the boat. The runners are sealed with epoxy, when that is cured, sanded and installed using epoxy thickened to a mayonnaise like consistency, the area where the runners are to be set is taped off, do this with the runners set in place so you will know exactly where they need to be placed. I used weights set against the inside of the runners, just touching them to ensure that they could not move while the epoxy cured. The weights, three per runner were set one at each end and one in the centre this helped when cleaning up as one could be moved and any excess epoxy cleaned up without too much fear of the runners moving. Scrape around the runner and pull the tape, once the epoxy has cured to the point that the runners are held in place run a small fillet around the outside of the runner.  Set the seat in place once cleanup is complete with a small amount of weight on it to help ensure that the tops are flat and will meet the bottom of the seat, it gives one last chance to make sure the mounting points are square to each other.

Notch spacing was set up based on moving the seat half the depth of the seat, while the notches were cut before the rails were installed, they were not drilled until after the rails were glued in place. This was done in case of any slight misalignment's, if everything was drilled before installation this would lead to difficulty inserting the bolts in some of the holes. Mark and drill the seats first to take the bolts, then use the seat as a template to drill the runners, I drilled the pilot holes for the insert nuts slightly undersized from the recommended size due to the softness of the cedar, to ensure the insert nut had a good bite into the runner. Don’t get careless with the drill it is not that far down to the hull especially at the front end of the runners where most of the shaping took place. Drill the aft end of the seat first then the forward side, to drill the next set move the seat ahead one set of notches drill these then move forward to drill the final set of holes. Seal the holes and insert the nuts, make sure you check that the holes are deep enough to take the bolts, by dropping them in with the seat in place before the insert nuts are installed.

When using this seat with a back-band, make sure that the back-band is cinched up tight to give you a solid base when paddling. At the present time I am working on a removable, solid seat back when the experimentation with it is complete, I will post an article on its construction and make up a plan sheet with a full size pattern.  

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