Building Instructions
General Tips:
We recommend that you follow the order of construction shown in this manual for the fuselage,
as it makes access to everything easier and saves time in the end. The wings and stabs can be
done at almost any point, and only need servos and control horns installing anyway.
The first thing to do is protect the finished paint on the outside of the model from scratches and
dents during building - so cover your work table with a piece of soft carpet, cloth or bubble-plas-
tic. The best way to stop small spots of glue getting stuck to the outside of the fuselage is to give
the whole model 2 good coats of clear car wax first,
but
of course you must be sure to remove
this 100% completely before adding any decals or markings. Additionally you can cover the
majority of the fuselage with the bubble-plastic used to pack your model for shipping, fixed with
paper masking tape, which also protects it very well.
When sanding any areas of the inside of the fuselage to prepare the surface for gluing some-
thing onto it, do NOT sand right through the layer of glasscloth on the inside foam sandwich !
It is only necessary to rough up the surface, with 60/80 grit or equivalent, and wipe off any dust
with alcohol (or similar) before gluing to make a perfect joint.
Before starting construction it is a good idea to check inside the fuselage for any loose glass
fibres that could cut your hands, and a quick scuff over any of these with a coarse Scotchbrite
pad will remove them.
Note:
It is very important to prepare the inside of the fuselage properly, by roughing up and
cleaning the surface, before gluing
any
parts to it.
Landing Gear
The 1st job is to fit the landing gear legs (wheel pants and
cuffs can be done later) - and you can leave these in place
to protect the bottom of the fuselage during assembly.
The Composite-ARF landing gear for the Extras consists of
45 deg laminated carbon fibre cloth and a huge number of
carbon rovings inside, all made under vacuum and heat-
cured. However it is still light weight, and retains enough
flexibility to take the shock out of any landings that are less-
than-perfect!
Mark the centreline on each carbon landing gear leg, and
drill 2 holes with a sharp 6.5mm Ø drill as shown in the
photo. The centres of the holes are measured from the
bend in the leg that will be flush with the outside of the fuse-
lage. The outer hole is 35mm from the bend, and the inner
hole is 58mm (2 5/16”) from the 1st hole. Both main legs
are identical, and can be used either side.
The carbon landing gear legs are secured to the revised
aircraft-grade plywood supports and bulkheads in the fuse-
Composite-ARF Extra 300SX
(2.6m span)
10
(above) The main parts used to
assemble the Landing Gear.
(below) Drill 2 x 6.5mm Ø holes for
bolting in the Landing Gear.