Composite-ARF SPARK Instruction Manual page 26

Composite-ARF SPARK
of Gravity location is almost perfect, only need-
ing the small RX battery for final adjustment. If
fitting your own larger packs it is important to
position them as far back as possible in the nose
area, to maintain the correct CG without having
to add weight in the tail.
The following instructions assume that you are
using a pair of packs of maximum size 165mm
long, 45mm wide and 55mm high, which can be
fitted onto the milled parts supplied in the kit
without any modifications.
Lightly sand the battery tray and make sure that
the small tab on the tapered end of it fits easily
into the milled slot in the rear bulkhead, which is
factory installed for you. In case you need to
reposition the slot in this bulkhead to suit differ-
ent shape Lipo packs we have included a small
ply plate with milled slot in it, that you can use a
'doubler' if necessary on the new slot position.
Glue 4 strips of the 5 x 5mm balsa onto the top
and bottom of the battery tray where your packs
will be, with thin CA, to maintain the air gap all
around the packs. They also stiffen the battery
tray considerably. Secure your packs onto the
tray using the double-sided Velcro band sup-
plied, with the connection wires at the rear end.
Do not secure the Lipos to the tray with cable-
ties, because the high pressure can damage
them. Of course you can modify the battery trays
a little to suit the shape and size of your packs,
and we have included 2 in the wood pack.
Assemble the front support bulkhead from the
milled ply parts as shown in the photo, and just
tack together with a little thin CA. Check that
your nose gear steering servo fits into the milled
plywood mount, and then also glue this to the
bulkhead. It is milled to fit a 15mm wide JR3341
or 3328 sized servo.
The battery tray is secured to the front support
using an M6 plastic bolt and large plastic nut,
supplied in the kit. Trial fit the bulkhead in the
fuselage, using your completed battery tray (with
batteries) to find the exact position it must be
glued into the fuselage.
IMPORTANT ! You must leave at least 10mm
clear space between the front of the lower bat-
tery pack and the back edge of the horizontal rail
techsupport@composite-arf.com
(below) Rear battery support bulkhead is fac-
tory-installed. The battery tray has a milled tab
that fits in the central slot, arrowed here.
(above) The 2 packs of 5200mAH 5S Lipos
secured to the milled battery tray.
(below) Battery tray is secured to the front
support with an M6 plastic bolt & large plastic
nut. Steering servo mount is glued into the
slot in the right side of the bulkhead.
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