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William R. Watt
 
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I haven't built a OSS or one of Gavin Aktkin's Mouse boats, but I've built
4 tiny plywood boats of my own design, two of them one sheeters (photos
under "Boats" on my website). (David Beede's "Summer Breeze" was the
inspiration for my one sheet "Delta" which in turn inspired the one
sheet "Prism" in Finland which can be found by a search of the Internet.)

"Paul Robson" ) writes:
Hi. I'm getting into boatbuilding ; as a rookie.

I was considering building one of the simple designs - say Herb's
One Sheet Skiff as a sort of trial run. I understand the
instructions etc. fine, but there's one part I don't understand.

In the design he has top and bottom chines (gunwales ?). The top
one is notched and fits over the plywood. The bottom one is angled
at 70 degrees (the sides slope so the boat has a flat bottom) - on about
8' x 1" x 2" strips.

This is fine, but I can't for the life of me see how to do this ! Any advice
is very much welcome.


Instead of cutting a notch the length of the gunwale (the one on top) you
can just screw it to the ouside of the boat. That's how I do mine. Drill
the holes beforehand and put in a few screws to see how it goes (called a "dry
fit"), take it apart, optionally spread some glue, then screw the gunwale on
again. Sand off the top edge so it's smooth. Then spread some plastic
resin of some kind (epoxy, polyester, polyurethane varnish) to seal and
protect the exposed edge of the plywood. My gunwales now tend to be made of
one or two 1/2" layers so they will bend without breaking.

Where the sides join the bottom is called the "chine" and the strips of
wood "chine battens" if they are on the inside, or "chine logs" if they
are on the outside. The way I cut them at an angle is to first cut a slice
off a 2x4 board (or 2x6 or whatever you are using). That gives a strip of wood
1.75 inches high. I then set the saw blade to the required angle and cut
the 1.75" strip in half. That makes two approx 0.75" chine battens with the
required angle (some of the wood, the width of the saw blade, is cut away by
the saw. I use a "narrow kerf" (ie. thin) saw blade.) TF Jones says 1/2" thick
chine battens are thick enough for small boats. It'sj ust easier to cut
a 2x4 into 0.75" thick battens.

If you own or can borrow a table saw cutting the gunwales and battens is
not hard to do. If you just have a hand held circular saw there are a
couple of ways to do it. The easiest is to plunge cut a slot in a scrap of
heavy plywood and screw the saw to it. Then turn the saw upside down and
you have an instant table saw. You have to wire the trigger closed and turn
it off and on by pulling the plug. Don't set the depth of the saw blade
any more than is needed. It's less scary without the whole saw blade
sticking up through the plywood. I screw a piece of straight material to
the plywood the appropraite distance from the blade to use as a cutting
guide. My guide is a scrap of drywall (plasterer's) corner bead.

I've also cut gunwales and chine battens by putting the 2x4 between 2
other 2x4's on a couple of saw horses, drawing a line where the 2x4 is to
be cut, and running the hand held circular saw along the line. Recently I
paid $10 for a simple cutting guide which attaches to the saw and lets me
cut faster than following a pencil line alone. The extra 2x4's help
support the weight of the saw. I've kept the wood from sliding around with
nails into the saw horses, and later with clamps when I got some big enough.

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