Building the Peace Canoe – time on the Moaning Chair

At the beginning of Howard Chapelle’s seminal tome Boatbuilding, there is a 4-page introduction in which Chapelle goes through the entire building process at a 10,000′ level. After talking through getting out molds, cutting the rabbet, and installing deck beams, Chapelle devotes the final paragraph to a subject that one must assume is of equal importance to the others: the “moaning chair.” He writes:

In every amateur boatbuilder’s shop there should be a “moaning chair”; this should be a comfortable seat from which the boat can be easily seen and in which the builder can sit, smoke, chew, drink, or swear as the moment demands.

I raise this, obviously, because I have had to spend some time in my own “moaning chair” of late, and since I don’t smoke or chew and had already had my nightly beer, it was swearing that was the business of the day.

You will notice two things in this recent picture. On the good news front, I finally have attached the seats to one side panel unit and then attached the other side panel unit to the opposite sides of the seats and brought both sides together at the stem and stern post. In doing that, I should have been working with completed side panel units, chine log and sheer clamp attached. So what are those clamps doing along the sheer, you may ask? Therein lies a tale…

Things were going fairly well. I got the seats and one side attached fine and the middle seat went onto the second side without a fuss. I then was able to get the forward seat attached to the second side. The bow was coming together. I then moved to the stern to pull the aft end together. I was feeling great – the boat was taking shape before me. As I began to pull the sides in to test, I was suddenly greeted by a sickening crack. I looked up to see the scarf joint in the starboard sheer clamp parted. Major buzz kill.

It seemed initially like the error was placing the joint right at the middle seat, where the sides are forced outward to the maximum beam. I dejectedly put the project to bed for the night, and, after mulling options for a couple days, decided to take out a roughly 6′ section of the sheer clamp and scarf in a new piece which straddled the middle seat. Getting the old piece off was a bear with all the 3M 5200 in there, but I did it without messing up the side panel very badly. I then got the new piece to fit nicely and added some additional screws to keep it all together. After that multi-day set-back, I was able to turn to bringing the ends together once again.

And therein lay another issue. I had misgivings on earlier attempts to test this, but when I was back on track and able to seriously try this task I discovered that the stem bevels I had faithfully taken from the Getting Started in Boats write-up were not even close. I had another couple days of sitting in meetings at work and trying to concentrate while ruminating on whether I should work the current stem and stern post or replace them. In the end, I decided the stern post was not far off, and I took a plane to the side that wasn’t fitting and got it right. Thank goodness the angle was too wide. The bow was really far off, but I decided to do the same. You can see in the picture how much I had to shave; the two laminated planks started the same width. Anyone who closely inspects the inside edge of the stem will find it isn’t perpendicular to the center-line, but I think I can get a pass on it.

I am not sure where I got so off with the bevels, because I am pretty sure my measurements were in lines with the plans. I think the issue does speak to a significant risk with building this boat, or any boat, in the manner the designer, John Harris, specifies. In most modern boatbuilding, one begins with a known set of truths: some combination of a level strongback, specified frames, a fixed centerline, and, probably, fixed ends. These elements for reference points the builder can rely on to check him/herself as s/he moves through the process. With the Peace Canoe, there are no frames or other fixed elements. You take measurements off the plywood sheets and, once you have made those cuts, you reference points are gone. You have no easy way to check something like your seat placements, which, in this case, are critical in forming the shape of the boat. This is because the location is set vs. the edge of the plywood, not anything you can look at on the boat itself. It is, as I have become fond of saying, boatbuilding without a net. I would strongly encourage Mr. Harris to continue to pursue ways to make boatbuilding easier for novices to access, but I worry he lost something important along the path to simplicity.

So now I was ready to finally bring the ends together, which I did. And as I looked up from the finished bow and sighted down the length of the boat… two more sheer clamp scarfs had parted. One was one of the joints from the first repair and the other was the port side one (originally there was one joint per side). Now it was clear there was a bigger issue. I did a little research, and I believe I have discovered the roots of my problem. The Getting Started in Boats write-up does not specify exactly how to do the scarfs, particularly how they ought to be oriented. It does say something to the effect that they should be 8:1, which for 3/4″ stock, means 6″. Against some doubt in the back of my mind I took that mean the scarf should be along the 3/4″ side of the sheer clamps, which are 3/4″ x 1″. Bad idea. What this does is put the scarf horizontal, and I believe that is not a good thing – there isn’t enough holding power in such a case once there is a bending force applied. The scarfs should have been vertical, and I have now cut out new sheet clamps with vertical scarfs. Next up: the fun of removing the existing ones in toto. Joy.

So for those settling down with the write-up, beware this point. Maybe I should have known this, but many using this won’t yet have the knowledge to realize the error. The write-up needs more clarification on this point.

Anyway, the bottom is ready to install now, as soon as I can get the sheer clamps fixed. Ugh. Where did I leave that “moaning chair?”

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