Not really a Micmac canoe

[Todd Bradshaw]

Strips were redwood with sitka spruce for the light stripes and an ash strip down the middle of the bottom. The sides were 1/4" thick strips. 3/8" were used on the bottom and 1/2" for the transom. The seats were mahogany and the gunwales were oak. There were three small oak keel-runners on the bottom. I didn't really have any problems while bending, but I did it slowly and the glass that had already been installed on the inside of the panels was being put in compression as the panels were bent. had it been on the outside and been in tension, it might well have been a very different story. The little seat knees were laminated spruce and just there to give the seats a bit more reinforcement. Most modern drifters have a more task-specific seat arrangement with a rower's seat and both a seat and some knee braces for standing anglers in the bow, but I wanted something a bit more universal.

One nice thing about drift boats for folks who are used to canoes is that unlike most rowboats, when you're on the river in drifter-mode, you're actually facing the direction you're going! None of this sitting backwards looking at where you've already been crap (something that always prevented me from warming up much to rowing and rowboats).

Typical drifter seating is more like this (this little model also has really nice lines. I think Dynamite Payson built it and it looks like it would make a very nice full-sized boat).

 

[pklonowski]

The paddles and rain coat only let you sail downwind, leaving the hard work for someone else. It's gotta be able to tack...

Inspiration for the sailing canoe concept came from Todd's book, which is available here at the WCHA store:
http://woodencanoe.org/catalog/prod...d=436&osCsid=d76d0ae2dc54107acf8d419cb6e29e4a

It's an awesome volume, and holds up to re-reading quite well.

I sailed a Grumman many years ago, and am keeping my hopes alive for getting a couple of canoes rigged. Things on the home front keep getting in the way.

 

[Dan Lindberg]

Mat,

Very nice. By now you probably have it varnished but I've been gone a week.

For reference, on my 1st , a 17.5 ft Winter's Winisk, 1 used the std 6 oz plus a sec layer in the "football". I believe I used about 2 1/4 or 1/2 gals resin, which was way too much. The trim was also heavy, I'm guessing about 18-20 lbs based on another canoe. The final weight on the 1st was 72 lbs.

Dan

 

[Todd Bradshaw]

No cringing at two full layers here. You run the risk of a few more tiny bubbles trapped in the weave and a couple pounds of extra weight, but with care, they're minimized. Keep in mind though, that most of the actual, in-use strength of a stripper is provided by the glass on the inside, not the glass on the outside. The types of forces and stresses that canoes generally need to survive are usually things pushing in on the hull from the outside (rocks, beaches and also just waves tending to bounce the bottom of the hull). These forces usually put the outer fiberglass layers in compression, and outer layers don't provide much resistance to compression. Being on the outside, they don't have to move very far. With a severe impact, the wood core would likely explode long before the outer glass suffered any sort of serious fracture.

By beefing up the outer fiberglass layers, you do create a thicker, tougher abrasion barrier, and possibly also increase the skin's puncture resistance a bit, but the increase in impact resistance, resistance to cracking, splitting or what might be considered all-around "strength" is very minimal. The outer fiberglass layers simply are in the wrong place to contribute that type of strength. In order to put those layers in tension, where they can actually contribute some serious tensile strength, you would need to do something like jump into your floating canoe from a cliff, or jump up and down in it while it's on the water or bridged between a couple of obstacles.

On the other hand, when a rock, wave or other force pushes inward on the hull from underneath, it puts the inside fiberglass in tension. It's literally trying to tear the inside glass apart and that inner glass skin is the main thing holding your boat together. So while the outer glass may be flexing, or maybe even creasing or starting to fracture as a result of a severe impact, all hell is trying to break out on the inside skin - and the inside skin is what's protecting the core and keeping it from splitting.

An awful lot of first time strip builders don't understand this whole compression/tension/cored composite scenario. You will see posts on forums where they typically announce that as their first project, they are building canoe "xyz" and in order to save weight, they have decided to use a layer and a half of six-ounce on the outside, but just a single layer of four-ounce cloth on the inside. They figure, as most folks would, that the rocks are on the outside, so that's where the bulk of the fiberglass needs to be. Unfortunately, it doesn't work that way - in fact, it kind of works the opposite way. Yes, they saved a few pounds, but in the process, they managed to throw away a huge amount of their hull strength and durability. All too often, these posts get followed up a few months later with one reading "Help! I hit a rock or went through some big waves, the bottom flexed and the inside of the wood core split right open all the way down the bottom! How do I fix this?" At that point, they're stuck trying to increase the tensile strength on the inside by cleaning off the varnish and adding more glass - not a pleasant task.

It's been pretty well shown over the last 40 years or so that on a typical recreational canoe, balancing the weights of the inside and outside layups seems to make a pretty tough boat with a couple layers of ordinary six-oz. cloth on each side of the bottom coring. There are certainly more exotic options that can save some weight or increase strength, but it's a really good idea to make sure that whatever you use for a cloth layup schedule, you maintain a well balanced layup. Don't skimp on the inside, because that's where most of the real strength is likely coming from.

 

[pklonowski]

I knew Todd would respond to this, and much more concisely & eloquently than I could, so I let him do it. Todd's right -- my own first boat was as he described (though the 6oz outside/4oz. inside was what came with the kit). He describes exactly what happened... bounced on a rock, outside had a little scrape, but it split the inside. It's not a difficult repair, but after a few too many of them, I ended up stripping the hull & re-glassing. That was not my idea of "fun"...

Retrospectively, I'm wondering if one layer on the outside might be preferable, not so much to save weight, but because it's much easier to repair rock scrapes/gouges in a single layer than double...?

But no, I won't be stripping the second layer off my boat any time soon. It's semi-retired, restricted to flatwater, so I don't have to fix it any more. Or so often, anyway.

 

[Dan Lindberg]

What Todd said.


And Mat,

Who said anything about "light fragile boats",
I want (and believe I built) canoes that are both lighter and stronger then with the std 6 oz layup.

Ya, I used to be able to portage the old grumman with no problem, but now that I'm older, the grumman got much heavier. (Just like how the rocks got harder.)

My goal for a (lake/BW) tripper canoe is 50 lbs, though I haven't and probably won't achieve that, the 2ed was 58 and the 3rd is likely to come in at about 53-54. Canoes 2 and 3 are 18.5 ft.

Dan

 

[pklonowski]

WHEEEEEEE!!!!!!!!!!!! Looks good from here! Congratulations!

 

[pklonowski]

I can't imagine a better reason to put the boat in the water! Tell her HAPPY BIRTHDAY!

 

[Todd Bradshaw]

Looks great! Did it handle better than your old one?

 

[Dan Lindberg]

Matthew,

Now that's the pic we wanted to see.

Congrats and nice job.

Dan

 

[pklonowski]

Aw, geez, it came out 3 pounds too light? Better start over!

Try taking about 1/4" of width off your wife's paddle, both sides, of course. Brely enough to notice visually, but will reduce the blade area by a good margin. Of course, then you run the risk of having her increase the cadence... Yeah, you're right... just rudder.

Now, the sail... Wouldn't it look great with a sail?