Completing The Skid Landing Gear; Fitting The Upper Fuselage Fairing - GRAUPNER Ecureuil AS 350 Montage- Und Betriebsanleitung

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Ecureuil AS 350

1.4 Completing the skid landing gear

Now that the skid bars are securely anchored in the fuselage, the skids themselves can be atta-
ched permanently:
First pull the skid tubes forward through the plastic connectors so that you can apply a little
UHU plus endfest 300 to the areas where the connectors will be located. Slide the skids back
again into their original position, remove excess epoxy with methylated spirit, and align the
landing gear once more with great care. Place the model on a flat surface and weight it down
until the epoxy has cured fully.
Remove the skids from the fuselage and carefully continue the 5 mm Ø hole for the skid bar
through each skid connector and into the skid tube, continuing the hole right through the pre-
viously fitted hardwood dowel to the opposite side of the skid tube, but take care not to drill
right through to the outside!
Cut down the top end of the skid connectors to an overall height of 23 mm, then re-fit the skids
temporarily on the skid bars, pushing them in as far as they will go. With the skids properly
aligned, check that the fuselage stands stably on a flat surface without wobbling. If this is not the
case, one of the holes in the skid connectors is deeper than the others and should be adjusted.
Failing this, grind off a little material from the end of the longer skid bar.
Now remove the skids from the skid bars once more. Bevel one end of the four ABS tubes (5/7
mm Ø) and slip the prepared ends onto the skid bars for a distance of a few centimetres. Heat
the skid bars in the area of the curve, e.g. using a heat-gun, so that the plastic tubes de-form
when pushed over them. Push the plastic tubes over the curved bars until they butt up against
the fuselage; the bevelled end should ensure a snug fit against the fuselage.
Heat up the skid bars only - not the plastic tubes! Heating the tubes causes them to
wrinkle, and prevents them sliding over the skid bars.
When the plastic tubes are in their final position, shorten them at the bottom end so that the skid
bars project by exactly 20 mm (i.e. the depth of the socket in the skid connector). Carefully
roughen these projecting rod ends using coarse abrasive paper; alternatively grind a series of
small grooves in them using a cut-off disc in an electric drill. Now apply UHU plus endfest 300 to
the sockets in the skid connectors and push the skids onto the skid bars for the last time. Check
that the upper ends of the connectors butt up snugly against the plastic tubes. Set up the heli-
copter on a flat surface as previously described and check that the skid tubes are exactly par-
allel. Weight down the fuselage and remove all traces of excess adhesive using methylated spi-
rit, then leave the epoxy to cure fully.
Round off the ends of the two running boards (H22), sand them smooth overall using fine abra-
sive paper and glue them in place: to the front end of the skid tubes and against the skid bars at
the rear.

1.5 Fitting the upper fuselage fairing

Locate the connecting lug in the front of the fuselage moulding above the windscreen and cut it
away, leaving a support surface of adequate size for the top fairing on both sides. Carefully trim
the upper fuselage fairing to fit on the fuselage and tape it in place. Since GRP parts inevitably
feature slightly irregular inside surfaces, the fuselage recess is deliberately moulded deeper
than required. This means that in virtually every case the peripheral flange of the fairing has to
be thickened to achieve an accurate fit. There are various ways of doing this depending on the
thickness of the material: two alternatives are to apply one or more layers of epoxy (after roug-
hening the surface, of course), and to apply strips of fabric-based adhesive tape. Fabric tape
offers the advantage that it avoids the parts rubbing against each other and rattling under the
influence of vibration.
When viewed from the front, the main rotor shaft should project centrally from the opening in the
top fairing. When you are confident that the fairing fits correctly, tape the fairing in place and drill
1.5 mm Ø holes through fairing and fuselage together to accept the retaining screws. Remove
the fairing and open up the holes in it to 2 mm Ø, so that it can be attached using twelve 2.2 x
6.5 self-tapping screws. Cut the doubler strip (H23) into small pieces and glue them over the
holes on the inside of the fuselage moulding. Continue the 2 mm Ø holes through the doublers
so that the screws have some "meat" to bite into.
The 5 mm beech ply glazing bar (H21) can now be fitted at the front, exactly in the centre; this
bar makes the area rigid, and also establishes the correct spacing between the main fuselage
moulding and the top fairing in the area of the windscreen. The windscreen can now be trimmed
to fit and attached using four 2.2 x 6.5 self-tapping screws at the corners.
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