Advertisement
Ignition and battery mounting
At this point in the assembly process it pays to think about where you
wish to place your ignition, ignition battery, kill switch and receiver
batteries. If you are using one of the current crop of light weight en-
gines such as the DA120 (2.25kg), you may need to place as much of
the on board weight as far forward as possible to obtain the required
C of G. Obviously if you are using an engine in the region of 3kg this
is less critical.
The ignition and ignition battery can always be attached to the engine
dome using zip ties, Velcro straps, or some of the after market
mounts that are currently available. There is a milled plywood throttle
servo mount in the hardware pack, this can be attached to the side of
the engine dome. The exact position of the servo mount can vary de-
pendant on your engine selection. All you need is for the throttle servo
arm to be at the same level as the carburetor arm. With the DA120,
the throttle linkage will be just below the LH lower engine bolt.
If you are passing the ignition high tension leads through the dome,
ensure they are protected and not resting against the cut fiberglass.
Rubber blanking plugs are ideal for this, simply punch a hole in them
and cut one side. Tygon fuel tube can also be used.
Option
One option is to place all of the batteries on a tray mounted behind
the firewall. This is a pretty simple process which will require some
3mm ply to make the tray. The ply tray needs to be shaped to fit be-
hind the firewall inside the engine dome. The shape of the dome may
vary slightly from model to model, so make a cardboard template first, then, you can make any adjustments necessary
before you start cutting ply.
How you place the items on the tray is dependent on the equipment you choose. As you can see from the pictures, we
had no trouble fitting everything we needed on the tray. One other advantage of the tray is, you can mount the throttle
servo underneath it. When mounting the tray inside the engine dome, keep in mind the throttle servo position. If posi-
tioned correctly you will have a nice straight path for your throttle push rod. We have provided a plywood throttle servo
mount in the hardware pack for you.
Sukhoi SU 31—2.75m/2.6m
Page|10
Advertisement
