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Pull/Pull Cables:
This is one area where the term Measure twice, cut once really
comes into play. While the job of fitting the pull/pull cables is not diffi-
cult, being sure of your measurements is important. While we have
supplied measurements for the cable slots, you should still make your
own measurements to verify that the positioning is correct. Small
changes to the assembly process and changes of equipment can al-
ter the outcome, so Measure twice, cut once !!
The first line we need to establish is the horizontal line, essentially the
plane the pull/pull cable will lay on. This process is quite simple and
will only require a few measurements.
You need to establish where the pull/pull cable meets the servo arm.
Use a straight edge on the canopy seat, measure to the top of the
servo arm. If you are using alloy arms, measure to the centre of the
ball link, this will be a few millimetres higher. Now that you have a
measurement, you need to transfer that to the outside of the fuselage.
Place some masking tape on the fuselage roughly where your mark
will be. With the straightedge on the canopy seat mark a line using
the measurement you just established. Now that you have the servo
arm position marked on the outside of the fuselage, you can use a
string line to mark the horizontal cable line.
You will need a couple of meters of string with a loop at one end. At-
tach the loop to the rudder horn using the 3mm bolts provided. Centre
the string loop between the control horns, then position the other end
of the string over the servo mark. Tension the string so there is no
sag, then hold in place with some masking tape. You have just estab-
lished your horizontal cable line. Place some masking tape on the
fuselage about 50mm from the rudder control horn. Using the string
line as a reference, use a rule to mark a horizontal line. You need to
cut a slot about 30mm long.
Flip the model upside down, and directly underneath the servo draw
the servo arm measurements onto some masking tape. Remember
this measurement is dependent on which servo arms you use.
Sukhoi SU 31—2.75m/2.6m
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