.
4.
Lay the sheets flat. Scrape off the excess glue with a squeegee made from a
balsa scrap. Finish glue cleanup with a damp rag. Weight down the sheets on a
flat surface and allow to dry thoroughly.
NOTE:
The grain of the wing skin sheet can
be on either parallel with the leading
edge or with the trailing edge. We
have tried it both ways and on this
shape wing can see no appreciable
difference in ease of application.
Both ways are shown. Use your
own preference. There is a little
more leeway for error in placement
on the edges of the piece with the
trailing edge method. And, it seems
to us easier to keep that critical
trailing edge true when it is placed
down and rolled parallel to the
grain.
5.
Sand the skins smooth with a sanding block.
6.
Wing Skin Sheet
Cut one 6-sheet piece diagonally in two, with
untaped side up, as shown by the dotted line
marked "A".
Cut the other 6-sheet piece diagonally in two, with
the untaped side up, in the opposite direction as
shown by the dotted line marked "B". This provides
4 wing skins with the untaped, rougher glue seam
on the outside surface of the wing. The smoother,
taped side should be used against the foam wing
for best adhesion of the skin to the foam. The
rougher, outer glue seams can be sanded down
partially with a sanding block before application of
the skins and completed during final sanding of the
skin on the wing.
CAUTION: Use only Sig Core Bond, Sig Kwik-Set, Sig Epoxy Glue or Sig-Bond Glue on the foam wing cores. Model
cement such as Sig-Ment, dope and fiberglass resin will attack and destroy foam. If you use any product other than
those listed, test them on a scrap of foam.
7.
Sand any irregularities or cutting wire marks from the cores with a sanding block.
8.
Glue the 1/2"x1-1/2"x2" balsa blocks WLB to the flat front of the core.
9.
Save the foam blanks to use as a cradle for sanding later. Saw WLB off flush with the core leading edge.