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Re: Elevator Trim Tab

> come on Brian tell the truth, you're thinking in terms of using them for
> the pitch axis of your autopilot project. Personally, I would be wary of
> the flutter aspects of using model type servos at the speeds associated
> with a velocity. Carefull attention to freeplay and reliability of the
> control pivot points high on the list of priorities.

Okay.  You got me.  That's exactly what I want to use it for.
I've been searching for industrial servos, but most everything
I can find are high speed constant velocity servos.  

I'm not decided on the servo to use.  Some of the hobby servos
are bretty robust with dual ball bearings and metal gears.

I haven't ruled out a MAC servo either.  I just haven't
received a lot of information about them.  Even the MAC servo
has plastic gears.  The good thing about them is that they have
practically zero lash, and they don't require power to hold their

How about this:
The servo I'm thinking about is the Cirrus 600.  It's got 330
in*oz. of torque which is a lot of torque.  They are cheap
enough at $50 each that I don't mind burning one up once 
a year.  Okay.  What if I make my trim tab hinge extremely
difficult to move such that it requires 150in*oz of
torque to move?  If the control linkage were sloppy, it wouldn't
flutter because it acts like a rigid assembly.

Since I'm thinking about using the same exact piano hinge that
we use on our ailerons and rudders, I'm confident in it's
construction and performance.  The thing I'm worried about 
is flutter from the control linkage, and this just might be
addressed with my idea above.


Brian Michalk  <http://www.awpi.com/michalk>
Life is what you make of it ... never wish you had done something.
Aviator, experimental aircraft builder, motorcyclist, SCUBA diver
musician, home-brewer, entrepenuer and SINGLE!