Canadair CL-415
7
Three aluminium hinge lugs (38) are used as the basis of the rudder hinge system.
Drill the 2 mm Ø holes and remove all rough edges. Cut down the lugs (38) approximately as shown on the
plan. Roughen the surface of the metal lugs as follows: place the lug on a hard surface, lay a coarse,
sharp file on it, and roll it to and fro - job done. Prepare the horns (39) in just the same way.
Part (96) is the tubular rudder shaft, while the plastic sleeves (20) act as a guide, making it easier to install
part (96) when the model is assembled. Parts (20) also serve as spacers between the three hinge lugs,
thereby limiting the axial play of the rudder. Please study the plan carefully here - the bottom end of all the
sleeves (20) should rest on the top surface of the hinge lugs (38). Assemble the rudder shaft (96) and the
hinge lugs (38) and (20), and carefully mark the position of parts (38) on the rudder. Cut away the balsa to
provide clearance for the lugs (38). Hold the parts together, keeping the pivot system central, and tack the
plastic guide sleeves (20) in place. Mark the position of the holes in the fin to accept the hinge lugs (38),
working as accurately as you can. Drill 2 mm Ø pilot-holes, then open them up to 4 mm Ø. Enlarging them
to the final diameter of 5 mm is best done with a round file.
De-grease the rudder hinge lugs (38), apply a little resin to them and press the rudder hinge assembly into
the fin. Position the system carefully, check that it is exactly central, then leave the adhesive to harden.
Remove the pivot shaft (96) so that the hinge assembly can be removed for further work.
Drill 5 mm Ø pilot-holes for the hinge lugs (38) in the channeled rudder leading edge strip (37), and glue it
to the leading edge of the rudder. Trim both ends of part (37) flush with the rudder, and finally trim the front
face. Note that part (37) should taper to a thickness of 3 mm at the top.
Sand part (37) to the section shown in section D-D, and trim the 5 mm Ø holes for the rudder hinge lugs as
shown in section E-E. Place the rudder in the fin, and check that it is free to deflect to about +/- 20° to both
sides of centre. If necessary trim the balsa strips (27) until this is the case. Remove the rudder and add the
top leading edge block, part (36) - see section C-C.
The fin should be glued to the fuselage without the rudder attached. The first step is to apply epoxy to the
snake exit slots in the stub fin, and pull the snakes out a little. Apply a little thickened resin to the edge of
the fin, thread the snakes into the appropriate slots, fit the fin and tape it in place. Fix the wing to the
fuselage and check that the fin is truly vertical, and that the longitudinal dihedral is correct! If everything is
in order, apply adhesive tape all round the periphery of the fin, and press it down onto the stub!
The time for
covering
has arrived. This model deserves a painted finish, i.e. we recommend that it should
be tissue-covered. Since most of the areas to be covered are fully balsa-sheeted (and because weight-
saving is important) we recommend lightweight 17 g/m² tissue, although you may prefer to cover the open
bays with 21 g/m² tissue.
The ailerons are already cut out of the wing, the lining pieces are fitted, and all openings are cut in the
wing. Apply thinned sanding sealer to the balsa surfaces and sand smooth using 400-grit abrasive paper.
Apply the tissue using thinned clear dope, then apply several more coats, rubbing down gently with 400-
grit paper between coats. Obvious irregularities should be made good using fast-setting filler. A perfect
white surface can then be achieved by painting the surfaces with slightly thinned white primer. Allow this
coat to dry really well, then rub down gently using 400-grit wet-and-dry paper, used wet. If you rub right
through the paint, apply a second coat of primer to those areas.
Sand down the GRP finlets (92) as shown, and cut openings for the tailplane; it is important to work
accurately here. Now it’s time to install the tailplane, after covering and priming it. Fix the wing to the
fuselage and align the tailplane carefully with it. The tailplane can now be glued in place with epoxy. Do
check the longitudinal dihedral before doing this! Mark the position of the finlets (offset approx. 2° to the
right!), slide them into place and secure them with thin cyano. Apply epoxy afterwards to strengthen the
joints. If necessary use small quantities of fast-setting filler (2-pack filler paste) to fill any gaps.
Motor nacelles
: sand the nacelles and motor fairings smooth overall. It is best to laminate the two-part
motor bulkheads (80) using epoxy. Be sure to round off the opening for the motor as shown on the plan
and in the photos. Use the motor mount as a drilling template for the 2.5 mm Ø retaining screw holes.
Install the mounts, and secure the nuts with thickened resin or Stabilit-Express.
Trim the periphery of the nacelle bulkheads (80) as required, position them carefully and fix them in place
with thin cyano. Trim the bulkheads (82) to fit snugly (they must not be a tight fit in the nacelles, or they will
produce an ugly distortion in the surface), and secure them using thin cyano. Cut pieces from the spruce
strip (81) as shown on the plan and glue them in place with cyano. Trim the cross-pieces (83) and (84) to
fit and tack them in place. When you are satisfied, apply epoxy to all the joints in one process, and apply
thickened resin where necessary to ensure strong joints.
The nacelles can now be trimmed to follow the wing section accurately; a little patience will be required in
order to obtain a perfect fit. This is also the best time to prepare the nacelles to accept the outer guide
vanes, which are fitted later - see Fig. 29 and section E-E. The sharp edge of the nacelle floor (outer side
of nacelle) should be extended with filler paste as far as the front edge of the outer guide vane. This is
shown in section E-E and Fig. 29. Caution: remember the nacelles are handed (different left and right).
Paint the inside of the nacelles matt black (Humbrol enamel or similar).
