Carefully sand and prepare the ply mounting plates,
the fibreglass flanges and the surface of the wing
spars where the plates will be glued. Glue in se-
curely using a slow epoxy and micro-balloon mixture
- making sure of good contact to the fibreglass and
the wing spars at the front and back of the retract
bays. An alternative is to use silicone adhesive, and
this has the advantage that it remains slightly flexi-
ble, and can be be cut out with a sharp knife if you
have to replace the mounts after an ‘accident’ !
Note:
Depending on the depth of your retract units
you may be able to glue the plywood retract mount-
ing plates
inside
the fibreglass sleeves, but in this
case you must be careful to get a very good glue
bond between the ply and the fibreglass because all
landing loads will be directly on the glue joint.
We recommend that you fit 2.5 - 2.75” diameter (Ø
63 - 69mm) wheels. Shown here is a Robart 2.75”
wheel, which fits fully inside the wing when retracted.
For the Spring-Air units shown, with a 2.75” diame-
ter wheel, the total leg length from the end of the
brass adapter to the centre of the wheel axle needs
to be 97mm. If it is shorter, then the wheel may foul
on the air nipple and tube on the end of the retract.
Carefully align the
sides of the wheels
exactly parallel with
the wing centreline
and secure firmly in
the adapters - or even
better is with about 1
degree of ‘toe-in’ on
each wheel for best
ground handling.
Route the air tube (&
servo extension ca-
bles) to the front cor-
ner of the gear bay
and secure in position
with a drop of silicone,
or equivalent, so that it
cannot foul the re-
tracted wheel. Trim
the molded retract
covers provided in the
kit as shown to make
covers for the retracts.
Small plywood tabs
Fox Composites Co., Ltd.
13
(above) Clamp ply mounts firmly to fibre-
glass sleeves while the glue cures.
(below) LG covers trimmed and taped in
place. Use countersunk bolts to secure
retracts for max. clearance if needed.
(above) Underside view of the completed right wing, with aileron
and flap servo hatches & retract covers secured with clear tape.
SpringAir 300/700 series retract, plain wire leg and Robart 2.75”
wheel shown. If you chose to fit trailing-link legs you will need to
reposition the retracts forward a little so that the wheels are in same
position as shown here.
