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outrigger man
10-30-2010, 09:17 PM
What weighs more 3/4 cedar glued and nailed or 1/4 inch cedar with 6oz glass on both sides. Any idea on strength difference also? Thank you

pumpkin
10-30-2010, 11:21 PM
I can't answer your question but this year I built an 18' canoe with 1/4 strips and 2 layers of 6 oz glass inside and out (4 total) that weighs 67 pounds finished. Take the amount of boards to build your boat out of 3/4" strip and weigh them, it should give you a rough weight to expect.

Matthew

johngsandusky
10-31-2010, 08:01 AM
I don't know the weights per square foot either, but my strip and glass melonseed is lighter than wood or fiberglass.

JimConlin
10-31-2010, 08:45 AM
If your cedar weighs 24 lbs.ft^3 and you use as much resin as glass, 3/4" solid cedar weighs about 1.5 lbs./ft^2 and 1/4" cedar strip sheathed both sides with 6 oz. glass and epoxy will weigh about 0.7 lbs./ft^2, less than half the weight of the 3/4" unsheathed panel.

With the grain, the 3/4" thick panel will be stiffer and stronger than the sandwich panel.
Across the grain, the sandwich panel will be stronger than the solid panel and about as stiff.

wizbang 13
10-31-2010, 10:12 AM
You might wanna add in the weight of vertical nails for the un sheathed version AND the weight of any water it may soak up.
Buiding 3/4 " square WO nails or sheathing is a mistake, gotta have one or the other.

Rich Jones
10-31-2010, 11:24 AM
Don't forget that you've got to add in the weight of a few ribs with the 3/4" method, as you won't have the glass lending support.

donald branscom
11-04-2010, 09:13 AM
Add in the ice chest !

Todd Bradshaw
11-04-2010, 11:24 AM
...and the fiberglass you'll probably add after the 3/4" cedar starts checking. I went through that with my solid cedar, 3/4" t&g glued plank Starboat. Once you get tired of patching cracks and repainting on a nearly weekly basis, you start looking for something to stabilize the outer surface (cross-grain veneer, fiberglass, etc.)