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Old Mar 21, 2007, 10:11 AM
n/a Posts
Flap Help in general :-)

Ok I just Finished the Bottom Flaps Mod on my Sharon HKM
getting abit more flaps now ..Its abit Hard sometimes
using my Vision Radio and having the Flaps go up and
Down Even at the end travel abit Weird
I have to keep changing the end travel abit ...

(keep in mind that its a long way and a lot of middlemen between the end of
your thumb and the servo's arm. Pots, springs, gimbles, electronic
components that by now on a Vision radio are more than 15 years old, maybe 20!)

Hi Mike,
First thing is this, bottom horns aren't a trick , they are the same linkage
we have been doing for years, and the same rules apply. Two hole arm on the
servo to a 4 hole horn on the surfaces.

One mistake I find is that some times guys don't mount the servos so that
they are flush with the bottom surface. Instead they just pot the servo to the
top skin and have to then either use a longer arm to reach up and out of the
hole (bad on a bunch of levels) or have to put a bend in their linkage to
clear the edge of the opening, or can't lean the arms toward the flap without
hitting the back edge of the opening.

With all the Tx's sub-trims and travels at Zero, servo arms should be
leaning toward the flap a notch or two, (the more the better for optimizing travel)
but leaving some 'push' possible for aileron/flap mix.

If your surfaces don't travel the same, its never the servo. Servos either
move or don't, they are 'told' what to do by the Tx and its programming. If
you do have a servo moving slow, it needs a new motor, it got cooked
somewhere along its life.

Servo arm length and position, and surface horn length or position are the
only thing that can affect travel timing...well other than something being
loose in the chain....that and TX programming.

That's the big reason for making sure you have all your electronics zero'd,
then adjusting your linkages to match. Subtrims clicks of under 20% don't
have much of an effect on travel speed, so after getting things to work, go back
and get your linkages corrected so that only very minor electronic
assistance is used.

Covering the top holes:
What I did was to use some color matched tape over the pushrod slot on the
top, I layed it in place then traced it out with an Exacto blade. Then I went
up to our bedroom found some big diamond earrings my wife has, popped out
the diamonds and glued them into the two holes where the screw-in horns were
supposed to go. That way when the plane is facing me and the sun, it sparkles.
A lot better than that flashy tape.

For the bottom, there are two options.
One you can go to Walmart and get some 3m photo laminate, its clear mylar
approx 3"x5", with a clear sticky back that peels off, cut that to fit the
openings, make small slot for the arms to exit and tape them in place, or I have
Volz servo covers in white that work great too.

Start over, zero your radio settings subtrim and travels, recheck your servo
arm positions and lengths, then adjust the linkages so that both flaps are
aligned on the wing, then program travels.


PS, You 9303 owners can get your TX all confused, because of those awesome
face trims, combined with menu sub-trims and Function Mode Trim assignments.
So same applies, once you get your sailplane tuned up, sit down, zero all the
face trim functions in all MODES, and go inside to the menu and zero those,
then reset your mechanical linkages to where they where before you cleared
everything. Also remember that FM and Com have two different effects on trims.
Remember about switch positions when you decide to touch a trim button
Be sure you understand them clearly. If you have questions about that,
don't ask me, contact your local company sponsored pilot, its why he's got on the
what do you do too cover up the Holes on the
Top and Bottom Surface of the Wing is there any Servo Covers
that will work nice for the Sharon and what about the Top
were the old linkage came out of the holes ..??
Any Help or Pictures of your center section closeup of the
Top and Bottom of were you change your servo to
bottom Hinge would be great Help thanks

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