Fred R. Klein wrote:
> -I'm troubled conceptually with the notion of coating the wings and control
> surfaces with as much as 1/4" of filler to be sanded and contoured which
> would seem to run the serious risk of altering the airfoils with uncertain
> results.
Sure can but is most critical in the first few inches of a laminar flow airfoil.
> -I'm concerned with the comment that improperly applied filler results in a
> surface which is too soft and vulnerable to dings in a fully-finished
> airframe.
Not good either, and too dry also makes it solvent-sensitive to a solvent-based
primer. But too wet and sanding becomes much tougher. SuperFil (or any
premixed)
exempts one from both the art and science involved, in exchange for $$.
> -I'm surprised to learn of the difficulties which apparently result in the
> event that an initial coat of filler is found to be insufficient and
> additional filler is required.
No surprise if you've done automotive bodywork. Depends upon how much waviness
you can tolerate after gloss coat applied. It sounds attractive to be able to
apply thick and then sand down deep enough so that basically one application
does it. In practice, the sanding of a large surface is much more laborious
to the point of not saving any time, in my exp.
> Is there someone out there who can spell out "the way"...or am I, and others
> like me, left to digest the instructions in the Europa manual with a grain
> of salt and thoughtfully consider the various ways previous builders have
> addressed this issue?
There's so much individual preference here, why not just buy a sample SuperFil
or such and try it along with expancel/laminating resin and see what you like?
You can safely have both on the same test surface.
Regards,
Fred F.
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