On Sat, 17 Sep 2005 11:45:10 -0400, Matt Colie wrote:

snip
Cutting guide reference slots is not a bad idea, you will have a lot of
wood to hack off before you get close to the sand-to-shape phase. You
might consider doing that before you even "cut the corners off" because
it will be easier to handle the blank then.

Well put. This was what I intended to describe but your command of
the English language is clearly superior.

I recommend Western Red Cedar (or similar light wood) for two reasons:
1) Easier to handle both while building and on the boat.
2) Easier to work on than oak.

I have shaped plugs out of MDF-blanks this way. A plug for a rudder
1.8 m long and with a 30 cm cord took only one evening to shape.
Painting, wet sanding, rubbing and polishing took much longer.

Thinking is the Cheap thing to do.

Indeed :-)

Here are some more ideas on shaping foils if you don't want to
make molds.

* Strip planking using 6-8 mm thick WRC strips. Use external frames.
Glass+epoxy inside, join halves and don't forget that you need
a good structural member running down the middle of the foil.
The exterior will need some final shaping, then add carbon as
needed and wrap in glass and epoxy. Potentially lighter than
the massive board for big boards but more work and less robust.

* Central structural member made from WRC+carbon laminate. Foil
shaped from foam cut by hot wire. Cover in glass+epoxy laminate.
Note, this time the laminate is structural.
My current boards were build like this some ten years ago.
They are 2.5+ m long and has a 44 cm cord. New they weighed
12 kg each.

/Martin