Binding Control Linkages
Problematic for Digital
represent a significant improvement in the accuracy and power delivered to a
model's control surfaces. As with any new technology there is always a
requirement to properly apply it or make adjustments in previously accepted
Because the digital circuitry is working so hard to maintain
a perfect neutral, any binding or impedance to the absolute free movement of
the surface will translate into more work for the servo.
surfaces should be especially free around neutral and easy to deflect beyond
the desired maximum travel as required to fly the model.
We can spend
a lot of time planning for this while installing the hinges and then get things
just a little too tight during the "gluing-in" stage of the hinging
Multiple trial fits of each control surface and hinge to its
mating wing or tail, and, the utmost in careful craftsmanship will produce the
It is a good practice to glue the hinges in after the
paint process is complete to avoid complications.
Some jets, like the
BVM F-4 and F-100, require ganging two servos to drive the stabilators. The
instructions are explicit that very fine adjustments of the linkages must be
made such that the servos do not work against each other. Properly adjusted
linkages have provided trouble free operation in the two "high time" factory
If half a turn on a clevis is still not producing the
desired result, you can drill the hole in one servo arm a few thousandth's over
size - example, the molded holes are .062" - use a #51 drill to make the hole
Expect some low amplified humming from digital servos - it is
normal, too much hum is not normal.
Volt / Amp Meter
Use an Ace
Volt master or similar device during the servo linkage installation process to
be sure that the linkages are finely tuned to produce the minimum current
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