GRAUPNER PILOT Bauanleitung Seite 33

Covering the wing
The wing should be covered using the tissue paper supplied in the kit. The first step is to
give the wing two coats of Hydro-Aerofix clear lacquer, carefully rubbing down after each
coat using 320-grit abrasive paper, Order No. 700.1. GLUTOFIX paste is used to attach the
tissue to the wing frame: the covering material must be applied carefully to avoid wrinkles,
and it is important that the grain of the tissue should lie parallel to the main spar. The
underside of the wing is covered first, using two panels of tissue. Cut the paper roughly to
size, lay it flat on a sheet of plastic or similar, and apply a coat of GLUTOFIX to the whole
surface, as if preparing wallpaper for hanging. Lay the pasted face of the tissue on the
wing, and gently pull it taut from all sides. Cut off the excess tissue, leaving it 2 mm
oversized all round, then wrap the excess "round the corner" and press it onto the balsa.
The top surface of the wing should be covered separately from wing rib (27) to the tip on
each side. The open bay between the centre section wing ribs (27) can then be covered
with two narrow strips of tissue for added strength. Cut off the excess tissue using a razor
blade.
Allow the wing to dry out thoroughly, then moisten the covering lightly using a spray bottle,
or a cotton bud dipped in water. The wing should now be pinned down to the building board
while it dries out; note that it must be packed up on a jig consisting of constant-thickness
strips of balsa (or scrap wood) because of the projecting locating piece. Moistening the
tissue causes it to shrink and become taut as it dries out. When the wing is completely dry,
give it several coats of Hydro-Aerofix clear lacquer; four or five coats are sufficient. There is
a danger that the wing will warp due to the lacquer's shrinking effect, but you can avoid this
by pinning it to the jig for a few hours after each coat. However, please allow the Hydro-
Aerofix clear lacquer to dry out slightly before pinning it down, otherwise the wing could
become stuck to the jig.
After the last coat you should leave the wing attached to the jig for at least 24 hours to dry
out thoroughly.
This type of covering is susceptible to moisture, i.e. the tissue will tend to slacken off
when damp (e.g. when left on wet grass), but it will become taut again when it dries
out.
Alternatively the tissue can be finished using solvent-based dope, but wherever possible
this must be carried out in the open air, or in a well ventilated room.
First apply two coats of Glattfix to the wing structure, rubbing down between coats using
320-grit abrasive paper, Order No. 700.1. After covering and water-shrinking, give the
tissue several coats of heavily diluted SPANNFIX Immun clear dope: mix the dope with
about half its quantity of thinners to obtain the correct consistency. Two to four coats of
dope should suffice. There is a danger that the wing will warp due to the dope's shrinking
effect, but you can avoid this by pinning it to the jig for a few hours after each coat.
However, allow the clear dope to dry out slightly before pinning it down, otherwise the wing
could become stuck to the jig.
After the last coat you should leave the wing attached to the jig for at least 24 hours to dry
out thoroughly.
Applying a colour finish
GRAUPNER GmbH & Co. KG D-73230 KIRCHHEIM/TECK GERMANY
Änderungen vorbehalten! Keine Haftung für Druckfehler! Id.-Nr.0061061 03/2010
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