Binding Control Linkages
Problematic for Digital Servos

Digital servos 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 practices.

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.

Control 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 process.

Multiple trial fits of each control surface and hinge to its mating wing or tail, and, the utmost in careful craftsmanship will produce the desired results.

It is a good practice to glue the hinges in after the paint process is complete to avoid complications.

Ganging Servos

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 prototypes.

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 .067".

Expect some low amplified humming from digital servos - it is normal, too much hum is not normal.

Volt / Amp Meter Check

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 drain.

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