In CAD you are doing pretty close to
what you might do with a planer.
Start by laying out 3 curves:
One on the deck where the rail starts.
One at the rail apex.
And one on the bottom representing the tuck.
In Pro/E you might use (offset) from
boundary curves to construct them.
Each of these curves can have multiple offsets
from the square edge of the unshaped ‘blank’.
In the tail, the tuck offset might be small;
perhaps .060" flowing to a more generous
.625 just forward of the wide point and then
becoming smaller again as you approach the
nose
Now instead of using a planer to foil a
surface between/thru the three curves you
use them as trajectories for a conic surface.
The surface will stay attached to the curves
as it sweeps along the outline and stay tangent
to the deck and bottom surfaces.
In Pro/E the feature is a multiple trajectory
sweep. There are a number of options that
define how this surface behaves.
Let the mathematical characteristics for the
curves and surfaces you define ensure that
the overall curvature in your final board is
smooth. Then start doing some CNC programming.
I used CATIA way-back-when before it became
a parametric modeler. That’s a CAD kernel
that allows any dimension to be changed, even
after it has other geometry linked/attached to
it. Pro/E was the first and probably still the most
powerful. But difficult to learn and the latest version
has become too user interface top heavy which
can rob productivity unless you have good macros.
CATIA at the time was a boolean modeler where
every thing was static and so you had to do it
right the first time or do it over. Not much power
in that. A parametric modeler lets you tweak the
curves and dimensions until you get just the shape
you are after.
-Hein
