Carf-Models Composite-ARF Extra 330L Instruction Manual page 13

Composite-ARF Extra 330L (2 x 2m)
techsupport@composite-arf.com
Sand a matching chamfer on the 4 milled ply-
wood squares (20 x 20mm), and glue them into
the cowling sides below the slots, with the inner
face as vertical as possible. Tack in place with a
drop of CA, and secure properly later with 30
minute epoxy/microballoons mix to fill any gaps
between the ply squares and the fibreglass.
When glue has cured drill a 3mm Ø hole through
the centre of these 4 ply squares and the fuse-
lage sides. Using M3 x 16mm bolts from the out-
side, fit the 4 milled ply parts with the holes in,
with blind nuts on the inner faces. Check that the
ply tongues are vertical, and adjust as needed.
Remove the ply tongues, and tape the cowling in
position on the fuselage. Transfer the positions
of the 4 tongues onto the fuselage and mill or file
the slots in the fuselage lip for the tongues.
Make the slots a fairly tight fit on the tongues.
Check that you waxed all the mating surfaces,
sand the 4 gluing areas inside the fuselage care-
fully, and apply a drop of thick 30 minute epoxy
and microballoons mix in each position, under
the slots. Bolt the 4 tongues into position on the
cowling again, and tape it into position, checking
alignment carefully, and then turn the fuselage
over quickly so it is the correct way up. After the
glue has cured you can remove the cowl, and fill
any gaps between the tongues and the fuselage
sides with a thick epoxy/micro-balloon mix.
Cut and glue in 2 small phenolic tongues in the
back lower lips of the fuselage with CA, and file
matching slots in the cowling flange for alignment. These
tongues only need to project from the fibreglass lip about 4 - 5
mm, otherwise you cannot get the cowling on and off easily.
When satisfied with the cowling fit, counterbore the 4 holes in
the cowling so that the heads of the M3 bolts sit
almost flush with the surface, and they bear on
the plywood plates that you glued in - not the
surface of the fibreglass.
13