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 Post subject: Re: Issaquah 14
PostPosted: Wed Apr 29, 2009 8:31 am 
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Joined: Sun Jun 20, 2004 8:03 pm
Posts: 1186
Location: South-central Michigan
Again, I like your analytical mind. I hadn't thought of placing buoyancy chambers low; I thought only in cubic feet of displacement.

You're right, I did double up the plywood in the middle, as that is the point of most stress if a boat is caught and trying to be bent double.

My spacers were cut from a 1" wide strip, that was about 1/2" thick. When I bent over to find a piece of wood to use, that one was the closest. (So much for analytical thinking, ehh?) It was too thick. I have two lines of spacers, one along the upper edge of the 4" strip of plywood inwhale, and the other along the bottom edge. They are set with the hypotenuse along those edges, and spaced alternately. A spacer on top, a gap on top, with a bottom spacer in that gap, etc.

This arrangement is a very stiff beam. My thwarts are lines, tied across from gunnel to gunnel. Unless a boat is being crushed sideways, there is no need for a stick in there to fight compression forces. Boats are usually in a situation where the ends are being folded toward each other, thus widening the boat more open. In that situation, the sides are pulling apart from each other, and a thwart is fighting tension. So, a lightweight line does the job for a tension load.

As I said earlier (I think) I drilled holes into each spacer, in an SPAM retentive attempt to lighten my boat. Probably got a whole 4-5 ounces off there! Anytheway, I also glued two of these to the floor of the boat, as cargo tie down points. These are placed just ahead of where my feet rest when I paddle in the center seat. I lash gear in the front, going back and forth between the gunnels. But, that leaves an opening at the back end of the load, so I run lines down to hose two tie down points to close it off, trying to keep gear from floating out in case of capsize. Cargo in the rear is contained end wise, by the stem end and the seat.

My Granddaughter sits in the very bow of the boat, in a stadium seat. As I age out of this boat, she is aging into it. I'm 71 now, and she's 8. In two weeks will be her third, week long river trip with us. She has a few day trips under her PFD too. She will be paddling some this trip. No little kids paddle anymore, a 220 cm kayak paddle like her Grandpa this year. I'll have to keep a weather eye out for the fast moving ends of that paddle, I expect.

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Kayak Jack
Doing what you like is FREEDOM
Liking what you do is HAPPINESS
I spent most of my money on whiskey and women - and I'm afraid I just wasted the rest.


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 Post subject: Re: Issaquah 14
PostPosted: Wed May 06, 2009 8:08 pm 
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Joined: Thu Dec 25, 2008 8:58 am
Posts: 30
The boat is complete and just went on her first trip.
I built simple plywood seats (must add some non slip) and coated the bottom with what turned out to be 2 very thick coats of graphite/epoxy I tried to keep the mix at 20% by volume but the resulting goop was hard to roll on in thin coats I reckon the 2 coats added nearly a pound of weight, with the rocks around here it probable won't last long.
The final weight with yoke and seats came in at 44lbs, it should be possible to come in 4-6 lbs lighter with some of the changes previously discussed plus less graphite.

Image

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A sample of the type of rocks in the background that lurk just below the surface waiting to grab the bottom in our area.

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The boat has performed very well as part of our first sea trial we took her out in a channel between a head land and an island with a fetch of about 4 km the wind was blowing a steady 20 kmph with higher gusts producing a nasty steep chop, not the conditions I would normally choose to go out in.
We had 2 small adults plus a 50 lb dog , who was less than thrilled, for a total of 300 lbs on board, we sat on the seats and never felt the need to assume the kneeling position although the ride was certainly lively, as one would expect plowing into it a fair bit of spray came aboard, I was expecting trouble going beam to the seas but everything was fine just the odd spray from wave crests, you definitely wouldn't want any lose heavy objects around though. We are also both used to how small boats handle in a seaway.
After that we felt confident enough to take the canoe on our first trip of the year through Kejimkujik national park and into the Tobeatic wilderness a round trip of around 30 km on water plus 10 km of portages which partially explains my fixation on the issue of weight. The canoe is light enough to pick up from the ground and place over your shoulders in one easy motion which produced more than a few curious looks from other canoeists compared to anything else I've ever carried its a joy but after 2 km you can still feel every ounce, the next one will be lighter!

On the water with the extra weight of packs of another 80 lbs for a total load of around 380lbs she was just hitting the sweet spot carrying her way well with great stability and not feeling at all loaded or sluggish, I would guess another 100 lbs of gear low down would only have improved things. For such a short canoe she kept up well with other canoes, in one 4 km stretch into a 10-15 kmph wind we pulled away from a couple of 17ft canoes, no doubt it would have been the other way around in calm conditions but the easily driven hull was easier to push into the wind and chop.
Altogether a great light tandem canoe

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Loaded ready to go, the space between the yoke and the front seat is reserved for the dog, I never added any stiffening to the bottom panels and haven't noticed any significant movement except when running over some granite boulders, which was probably a good thing.
The graphite already has a few scratches in it through to clear epoxy which is to be expected, nothing stands up to granite boulders without a few battle scars.


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 Post subject: Re: Issaquah 14
PostPosted: Wed May 06, 2009 9:01 pm 
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Joined: Mon Aug 04, 2008 12:01 am
Posts: 464
Location: Portland, Oregon
That is a beautiful boat that you built.

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Craig
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If I had more clamps, I could build more boats.
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 Post subject: Re: Issaquah 14
PostPosted: Wed May 06, 2009 10:46 pm 
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Joined: Sun Jun 20, 2004 8:03 pm
Posts: 1186
Location: South-central Michigan
You're going to enjoy camping in this boat. You have a very versatile craft there. Solo or dual, it will do a lot of jobs for you.

_________________
Kayak Jack
Doing what you like is FREEDOM
Liking what you do is HAPPINESS
I spent most of my money on whiskey and women - and I'm afraid I just wasted the rest.


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 Post subject: Re: Issaquah 14
PostPosted: Wed May 06, 2009 11:09 pm 
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Joined: Fri Jul 18, 2008 10:12 am
Posts: 388
Location: Seaford, South Oz
Yep, she's a beauty all right!

I'm surpsised at how little difference the scuppered gunnels made to the weight - just shows how decieving looks can be. They do look good though and have other advantages.

Must say you're braver than I am - don't think I'd be game enough to take it through those granite boat eaters.

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Cheers, Bob

Laker 13 - christened and slimed (just).
Laker accessories underway.


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 Post subject: Re: Issaquah 14
PostPosted: Thu May 07, 2009 12:59 am 
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Joined: Mon Sep 10, 2007 10:15 pm
Posts: 129
Location: north Georgia, USA
It is a beautiful boat and some pretty water to canoe in.


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 Post subject: Re: Issaquah 14
PostPosted: Thu May 07, 2009 5:46 am 
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Joined: Mon Dec 17, 2007 7:03 am
Posts: 300
Location: Melbourne, Australia
Lovely looking boat. Nice work chinook :D :D

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John.
1 Cape Fear Sit In....a couple more planned
2 Laker 14's
1 Paddle board

"People who don't make mistakes don't make anything"


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