REFLECTOR: Air comes from spar/foam

[Alan Shaw <wingco@iu.net>]

R. Wayne Owens,

> > > > occurred over the spare area, only over the forward surface

Velocity wing construction is very different than Easy's here because the
Spar is pre molded.  It is difficult to fit and fill the area between the
spar and foam blocks by hand without leaving pockets of air hidden.  The
air left in this area expands, leaks to the skin and causes problems.  In
the molds we have the advantages of pressure and vacuum to minimize the air
that gets trapped in the wing but some always remains.  We have worked out
a procedure for molding the spar at the same time as the wing....that saves
a lot of time and money too, but change is hard to impose on a 14 year old
procedure.

Hard shelling was done for two reasons.  One because the Safety-Poxy used
on Velocities has some styrene that eats into the foam and adds resin
weight.  The other is that the micro balloon surface could be sanded true
and glassed clean and straight.  The problem was when dry micro instead of
runny slurry was used and the lay-ups were squeegeed too dry.  Even without
hard shelling dry micro slurring and lean laminations cause the same
problems.

Any delams bigger than 6" in any direction probably should be slurried
across the area with the aid of an Air Vacuum Pump from Harbor Freight
Tools 1-800-423-2567  item # 03952-4CXH   $9.99+S&H.


Alan