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Composite-ARF INTEGRAL
techsupport@composite-arf.com
control horns, mill the slots as described in the stabiliser section, but make the slots at least
20mm (7/8") deep. The holes in the horn (for the clevise) should be perpendicular to the hinge
axis in the 'neutral' aileron position.
Servo mounting plates (6mm lite-ply) are laminated into the underside of the wings during man-
ufacture (photo P9). These mounts fit 'standard' sized servos of approx. 20 x 40mm (eg: JR
8411, 8611/Futaba 9151, 9155)
Cockpit Canopy
The standard canopy is a one-piece lightweight fiberglass moulding, but cockpit bases and clear
canopies are also available as options. The canopy must be securely fixed, especially if using a
glow or gas motor, because of its large size, and it needs at least a 4-point fixing to maintain the
torsional stiffness of the fuselage. Included are phenolic hooks, 1.5mm ply for the tongues/hook,
M3 bolts with T-nuts, and enough 3mm lite-ply sheet to make your choice of fixing.
There are several ways to fix this successfully, but we used a similar system to that used on our
large aerobatic planes because it is secure, and rattle-free. It is fixed with a plywood hook at the
front, that slides under the lip on the fuselage, a pair of plywood tongues with M3 bolts and T-
nuts in both sides about 50mm (2") from the back, and a small phenolic tab that locates the cen-
tre of the canopy into a slot in the fuselage at the upper back position.
Make the hook at the front first, using the 3mm and 1.5mm plywood sheet as shown. First glue
a 3mm plate inside the front of the canopy, then use a spacer of 1.5mm ply - and finally make
the hook from 1.5mm ply with the grain running longitudinally. 2 scrap balsa strips, glued inside
the fuselage, keep the hook is exactly centred, and the excess length is sanded off afterwards
(see inset photo). Work thru' the bottom of the engine bay, with the fuselage upside-down. Lastly
secure the plywood plates together with 2 very small sheetmetal screws as shown, for safety.
Then make the small phenolic tab at the upper back of the canopy, which must fit tightly into a
slot filed in the fuselage. Reinforce the joint between the tab and the canopy with 3mm lite-ply,
and also glue a small piece of lite-ply inside the fuselage to reinforce the slot. (See photos P10,
11, 12 and 13)
Finally make the 2 tongues for the M3 bolts and T-nuts in the sides as follows: File 2 narrow slots,
35mm long and 3mm wide, in the flanges of the cockpit opening - with the front of the slots about
60mm from the back corner. The outside edge of the slots should be about 3mm from the out-
side surface of the fuselage. Cut 2 squares of the 1.5mm plywood sheet, 15 x 15mm, and glue
them to the inside the fuselage, under the flanges, with epoxy and microballoons, at the front of
the slots. The inside surface of the ply squares should be flush with the outside edge of the slots.
Cut 4 pieces of 1.5mm ply 30 x 15mm and laminate together with thin CA to make the 2 tongues.
Align the tongues with the squares and drill thru' the centre of each and right thru' the fuselage
sides, 3mm diameter. Open up the holes on the tongues only to Ø 4.5mm, and glue an M3 T-nut
to each. Bolt the tongues in place with M3 bolts, with the extra length projecting up through the
slots in the fuselage flanges (see P14, 15 and 16). File small slots in the bottom flanges of the
canopy to accept the tongues. Apply a little thick epoxy and microballoon mixture to the inside
surface of the canopy, where the tongues will be, and then quickly install the canopy onto the
fuselage. When cured, remove the canopy and reinforce the glue joints properly with more
epoxy. Fine adjustment of the canopy alignment can be done by sanding or shimming the outer
surface of the tongues or inner surface of plywood squares. Counterbore the holes in the out-
side surface of the fuselage a little so that the bolt heads sit nearly flush (photo P16).
Dont forget to extend the slots in the fuselage flanges at least 15mm backwards, before gluing
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