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I'm building the Mystic River Canoe from plans. I had a few stripping concerns:
1. For better or worse, I could only transport 9' planks so will need to connect them. Should I randomly place all the splices so they don't stand out? (Otherwise they'd all be in the middle of the canoe)
2. For scarfing, Nick shows two methods, the standard scarf -or- one at an angle that can be used while buidling.. Will these still look as good as a normal scarf?
3. When I scarf the gunnels, how long does the scarf need to be for 3/4" wood?
I'm sort of regretting 9' planks when I consider the number of splices I'll need to make.
This is my first stripper so I'm not expecting it to be perfect...
Thanks for any words of wisdom..
4 replies:
RE: Canoe Stripping questions
Chenier's suggested "A standard scarf is 8:1 - That works out to 3" for 3/4" wood. Longer won't hurt. I'd do stress tests, though, if you want shorter."
Um, maybe it was a typo (no editing available here!) but with 3/4" stock a 1:8 scarf takes 6", not 3. (0.75" x 8 = 6.0" by my math....)
Here's more on scarfing. Longer is better - strength of the glued joint is dependent on surface area so shorter joints are weaker than longer.
As mentioned though for a stripper hull those scarfs are typically supported on both sides, even more so if you go to the trouble of milling cove-and-bead edges on the strips before assembly (more surface area again).The strength of the resulting shell is from the inner and outer fiberglassed encapsulation, not the wood core.
RE: Canoe Stripping questions
... and for the two scarf 'styles'?
Traditional has the bevels planed across the widest dimension of the workpieces so when assembled you see a diagonal seam along the outside edges, what looks like a straight butt seam perpendicular to the edges on the face.
With strippers it's often just as effective and a fair bit faster just to saw carefully across the face of two stacked strips so the seam once formed is diagonal across the face. Cove & bead here's a big help when aligning the two ends but even with square edges any slight misalignment is quickly remedied when it comes time to fair the hull's outer surface prior to 'glassing.
RE: Canoe Stripping questions
» Submitted by Chenier - Tue, 11/5/19 » 7:25 AM
>> 1. For better or worse, I could only transport 9' planks so will need to connect them. Should I randomly place all the splices so they don't stand out? (Otherwise they'd all be in the middle of the canoe) <<
Yes. Not only will it look way better but it also won't give you a line of weakness across the canoe.
>> 2. For scarfing, Nick shows two methods, the standard scarf -or- one at an angle that can be used while buidling.. Will these still look as good as a normal scarf?<<
At Okumefest Nick told us to just butt two cedar strips together - don't waste time fooling around with scarfing. During construction the glued strips on either side will hold the joint together. Eventually you'll fiberglass the hull inside and out - that will hold the butt joint together permanently. The main strength of the assembly comes from the fiberglass sandwich with the wood holding it apart. As long as the wood holds the fiberglass layers apart it doesn't matter what kind of joint you use in the wood.
From the outside (or inside) you can't tell the difference between a cleanly made butt joint and a cleanly made scarf. They both give you a joint line perpendicular to the long axis of your strip.
I'm not sure what you mean about a scarf at an angle, as all scarfs are at an angle. Perhaps the scarf angle is cut perpendicular to the broad face of the strip? No reason that wouldn't work structurally. It would give you an interesting effect where strips of dissimilar color meet.
>> 3. When I scarf the gunnels, how long does the scarf need to be for 3/4" wood?<<
A standard scarf is 8:1 - That works out to 3" for 3/4" wood. Longer won't hurt. I'd do stress tests, though, if you want shorter.