Carf-Models Ultra Flash, Instruction Manual

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tank and give you the maximum fuel capacity.
Included in the hardware is a felt clunk, or you can use a
normal clunk if you prefer. Connect the clunk to the brass
‘feed’ tube with Tygon, and make sure that it almost reach-
es the back end of the tank. If you fit the hopper tank in the
recommended position on the floor at the back of the cock-
pit you can bend the brass tubes a little to the right side
where they extend out of the front of the tank so that the
fuel tubes clear the hopper tank support. The feed line
from the clunk in the wing tank is connected to the ‘vent’
on the main (fuselage tank).
Fit the completed tank in the tank bay, and glue 6 or 7
small blocks (cut from the 10mm balsa strip included)
around the edges with thick CA to prevent the tank moving.
(see photo P10). To gain additional space for the wing
tank, if needed, you can sand away the 2mm foam sand-
wich strip on the front of the wing spar, which is used in
the manufacturing process to locate the carbon rovings.
Trim a large enough round hole at the front of the tank bay
for the tank cap, and also the wing servo cables and
retract tubes, to exit.
It is most convenient that the overflow/vent tube is posi-
tioned in the tank bay itself, right at the back of the tank so
that you can put the Flash on it’s nose for assembly at the
airfield. Glue a short length of the 4mm brass tube into a
small block of the 10mm thick balsa strip, drill a 4mm hole
in the bottom of the wing immediately in front of the wing
spar for the tube to exit under the wing, and glue the block
into position as shown (right). Connect the vent/overflow
tube from the tank with the tubing supplied. Connect the
‘feed’ from the clunk in the wing tank to the ‘vent’ of the
fuselage tank, using the 4mm I.D clear tubing and the
‘push-fit’ connector included in the wing tank hardware.
Fuelling
Because the fuselage tank has a baffle in it, it is important to
remember to fuel the model until the excess comes out of
the overflow/vent under the model, and then wait for a few
seconds before topping it up again. If not, you may end up
taking off without full tanks....
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(above) Vent/overflow tube posi-
tion inside the wing tank bay.
(below) Wing tank bay is cut and
hinged for you at the factory.
(bottom) Secure the tank bay
cover with a couple of the small
sheetemetal screws, into small ply-
wood tabs glued under the lip at
the front corners.
(above) Completed wing tank,
ready to install in the tank bay.