‘plane to achieve the correct Centre of Gravity, it is better to install a larger Nicad - rather then
add lead.
When using a gas engine we highly recommend a ‘Powerswitch’ for the ignition cut-off, which is
available from C-ARF.
If fitting the switches into the outside surface of the fuselage, as shown, you should reinforce the
area inside with a small patch of 3mm thick plywood to reduce vibration transmissions to the
switches. The Powerbox switches come with paper templates for cutting the slots.
NB:
Please double-check the manual for your R/C system if the use of 5-cell battery packs is
recommended, or not.
Motor ignition system
The ignition unit can be secured onto the top of the exhaust tunnel, as previously mentioned,
using 2 or 3 small cable-ties. We advise that you mount it either on a foam pad to protect from
vibration. At C-ARF we recommend a 4-cell 1000 - 1200 NiMH for ignition, and we use a
Powerswitch for the ignition cut-off. Add a very small cable tie around the plug/socket connec-
tors from the motor pick-up to the ignition unit for extra security.
Servo extension leads etc.
We advise you to use good quality twisted-cable extension leads, of heavy gauge wire with gold-
contact connectors. Secure all loose wires and extension leads - remember that when you are
pulling those 10G manoeuvres everything in the plane has 10 times more force than usual! Be
very careful to fix all your batteries securely.
Make extra sure that no fuel tubes or cables can come in contact with hot exhausts.
Fuel proofing
If fitting a gas or glow motor we highly recommend that you protect both sides of the plywood
firewall, and all the bare wood parts and edges inside the front of the plane with one thin coat of
24 hr laminating epoxy, or similar, brushed on. Be careful not to add excess weight here - it only
needs about 25 - 30 grams (1 oz.) of epoxy to fuel proof all the wood in the whole area in the
front of the plane.
Final check
Check that you have fixed all components securely. Keep in mind that everything inside the air-
craft is loaded with the same G’s as the wing and the wing spar during aerobatic manoeuvres.
Check engine, cowling, wing and stab mounts carefully again.
-
Are all extension leads, cables and fuel tubes securely fixed to the side of the fuselage ?
-
Are all tubes/wires protected from chafing where they pass thru’ the holes in fibreglass
parts or bulkheads with rubber grommets, or short lengths of split silicone tubing?
-
Make sure that no fuel tubing or wires can come into contact the hot exhaust.
-
Did you fit short Tygon or silicone tube pieces over all the clevises?
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Did you tighten the M3 locknuts against all the clevises?
-
Are the swages crimped up nice and tight on the rudder cables?
Composite-ARF Extra 300L
(2.12m/84”)
29
