considerations. We have used a foam-board plate, reinforced underneath with a couple of balsa
sticks, and glued to the fuselage sides with epoxy and micro-balloons. This plate also holds the
Receiver and (optional) switch, and only weighs 22 grams - a stiff and lightweight solution.
Whatever mounting system you use we advise you to fit the wings to the fuselage before gluing
in the rudder servo mount - so that you cannot accidentally deform the fuselage. Use your choice
of servo arm on the rudder servo, preferably with the linkage hole centres at about 60mm (1.75”)
to match the hole centre spacing in the rudder horn. In these photos we used the phenolic C-
ARF rudder servo arm from our 2 x 2 Extra kit.
Linkage was by the usual closed loop pull-pull
system.
Motor Installation
The new C-ARF Impact design allows so many
different choices of power unit that it’s impossi-
ble to provide mounting bulkheads for all of
them, and it is our experience that many pattern
fliers have their own preferences anyway.
Therefore, depending on your choice of
methanol/gas/electric engine you may need to
modify the ‘generic’ milled parts we have includ-
ed, or even make a few of your own.
No engine mounting hardware is included in the
kit, because of the many different set-ups and
engine choices.
Glow or Gas engine installation
Included in the kit is a generic composite car-
bon/plywood/carbon nose ring and firewall (see
photo right). The firewall suits most typical
motors, such as OS140/160, YS140, Webra
145, Mintor3M 140, etc, or even one of the new
small gas engines. If using one of these typical
motors we recommend using a ‘Hyde’ type
mount, without a nose ring. Alternatively you
can purchase our optional ‘Engine soft mount’,
formerly designed for the Revolution Pro, which
includes machined aluminium beams and all the
other parts to build a lightweight beam mount
with softmounts at the back and front. (see pho-
tos right and website).
If fitting a ‘Hyde’ mount, trial fit the firewall into
the fuselage, at the correct distance from the
nose to suit you motor and mount, and also at
approx. the correct sidethrust and downthrust, and check carefully that it does not deform the
fuselage sides at all. Sand the perimeter as necessary to make it a sliding fit. Trial fit the mount
to the firewall, and the firewall in the fuselage at the correct distance from the front of the fuse-
lage to give about 1.5 - 2mm clearance between the spinner backplate and the fibreglass. An
Composite-ARF IMPACT
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