This post will serve as an introduction to the greater topic of paddling and allow me to meander to thoughts about water, especially salt water, without which there would be no need for outrigger paddling. These thoughts about our planet ocean tie into the repair thread in that I am taking into consideration the force of the collision between the hull and the standing waves of water. I discussed this with my repair mentor Gil, and while it is certainly impossible to calculate where the bow bounces against wave peaks the most, the last thing I want is the hull to crack like an egg against waves or any flotsam.
I am guilty of salvaging a 1966 Chevy Chevelle that had a tree fall on it, but it's hard to sink in an old Chevy. If I get my boat repair wrong and hit a reef, so to speak, this could be life threatening. This hull repair must be brought to 110% integrity. Okay, how?
While it was decided that the top of the canoe should be cut open to fix it from the inside, there was concern about the possibility of new damage to the location brought on by new surf stress, which could lead to "catastrophic failure." Yikes. I decided it might be best to insert some XPS insulation in the area to provide strength, and came up with this initial design:
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| XPS INSULATION SCHEMATIC |
Just how hard is water in motion, and what kind of stress can a boat handle? I don't know, but after I came across
this post on a craft marooned on a reef, once again, I felt a little better about my prospects.
Much better to add 4 ounces of XPS (fancy name for foam) with a compressive strength of 25 psi (pounds per square inch) to take any future blows than risk cracking the hull. While the foam might add 4 ounces to the canoe, I'll just have to go on a diet to offset it!
The foam brings one more aspect to the hull: it is buoyant.
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| XPS INSULATION FROM DOW, 25 PSI |
If things didn't float on our ocean, there would be no paddling. So, why do boats float? The answer is buoyancy, which is actually a physics term. It means an object will float if it is less dense than the liquid under it. The pressure from the ocean is "upthrust" and is pressure against the object trying to displace it. The shape of a boat, or in this case, canoe, lends itself to buoyancy. This canoe is like a carbon fiber bubble where the length provides even greater stability.
The hull was cut open, and we took a peek under the "hood."
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| CARBON FIBER JIGSAW BLADE |
A Dremel was used to make the first incision, but I decided I'd get a smoother continuous cut from a jigsaw and ordered the Bosch carbon fiber blades online.
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| SCRIBED CUT LINE AROUND TOP OF BOW |
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| AND LOOK WHAT WE FOUND INSIDE? XPS INSULATION! |
The XPS insulation discovered inside the hull seemed to be original to the canoe's creation and likely was meant either to hold things in place while the top was originally glued on or did serve some purpose for cushioning bounce. 4" holes are cut into it like Swiss cheese, presumably to cut down on unnecessary ounces.
TO BE CONTINUED
