GRAUPNER Heim Eurocopter Bo 105 CBS Mode D'emploi page 53

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Bo 105 CBS
This assembly can now be attached to the mechanics using two M3 x 16 socket-head cap
screws as shown in the illustration. Place the assembly in the fuselage and tighten the retaining
screws. Provided that you previously adjusted everything correctly, bulkhead 5 should now rest
snugly - but not tightly - against the recess of the fuselage shell; if necessary adjust the slots in
the braces, or re-position the brackets. Fix the bulkhead to the fuselage using two 2.2 x 9.5 mm
self-tapping screws, maintaining the stated spacing to the support flange. After a final check that
the mechanical system is correctly aligned, and that the main rotor shaft is correctly positioned,
glue the two braces to bulkhead 5 using thin cyano, then run thick cyano along the joints for
extra strength.
The entire bracing system can be removed again after undoing the two socket-head cap screws
and the two self-tapping screws, so that you can roughen up the joint areas of the fuselage
moulding and apply the epoxy (UHU plus endfest 300) which bonds the bracing system
permanently to the fuselage. Fit the self-tapping screws again to ensure correct positioning
while the glue cures. Please note that you can postpone this process if you prefer to have
improved access to the rear part of the fuselage for the next few stages of construction.
1.5 Attaching the upper fuselage fairing
Carefully trim the upper fuselage fairing to fit the support flange on the main fuselage, and tape
it in place when you are satisfied. Check in particular that the moulded-in seams and the edges
of the maintenance hatches line up exactly. Since GRP mouldings inevitably feature irregular
internal surfaces, the recessed flange on the fuselage is deliberately deeper than the thickness
of the upper fairing, i.e. the fairing edge must be thickened in order to obtain a really accurate fit.
Depending on the thickness of the material you can apply one or more coatings of epoxy glue -
after roughening the surface, of course. Alternatively you can apply strips of adhesive cloth
tape; the advantage of tape is that the parts do not rub or chatter against each other under the
influence of vibration. The main rotor shaft must exit the circular opening in the upper fairing
exactly in the centre; if not, adjust the opening until it does. You may have to open up the hole
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