I'd go with Martin's recommendation of materials. A white oak board, while
maybe stable, will be too heavy to handle.
Google for a NACA foil design program.
For shaping it, I'd use a router as the shaping tool. Make a slotted
'bridge' which will guide a router over the victim. The bridge can run
either the long way or cross-ways. If the bridge runs the long way, it can
be straight but rest on curved templates at the ends of the board. If the
short way, the bridge must be curved, but it will run on straight guides at
the edge of the board. I'd favor the short curved bridge, which will flex
less.
"Schöön Martin" wrote in message
...
"Toller" writes:

snip

I bought some 8/4 white oak on ebay for almost nothing (100bf for
$1.25),
and figured I will build a new daggerboard while I had something intact
to
copy.

The blank is 44" long, 2" thick, and 15" wide. It weights 35 pounds.

Question: Is this a massive plank or quarter-sawn strips glued together?
If it is a massive plank you should count on it warping.

I originally intended to cut the corners off on my table saw, but it is
so
heavy that it doesn't seem particularly safe.
So, I have been going at it with my 3" belt sander and my 2" power
planer.
Both would work, but they would take hours and hours of work.

Any suggestions for a good way to shape my blank into an airfoil shape?
I am thinking of buying a better planer, but hope someone here will be
resourceful.

This is probably the wrong answer but I actually mean this:
Use the oak for something else. Buy some light wood like Western Red
Cedar and shape a board. Add unidirectional carbon for bending
stiffness and strenght. Sheat in glass-epoxy and paint.

A WRC blank should be light enough to handle on the table saw.
Cut grooves to a depth that just 'touches' the future profile.
Use a power plane to remove material almost down to the future
profile and then continue with a hand plane and long board sanding.

Have someone calculate how much carbon you need and then use a
router to cut out some material from the WRC board so you can add
the carbon without ruining your profile.

More on boards at:
http://hem.bredband.net/b262106/Boat/dagger.html

--
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Martin Schöön

"Problems worthy of attack
prove their worth by hitting back"
Piet Hein
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