Futaba Servo s9650 - gear play
 

Hello guys,
I would be very glad to hear some experiences from those of you who use / used the 9650 digital mini servo.

I installed two of them in the stabs, made a very tight control linkage (great mechanical advantage with ball links - no play here) and then, holding the control surface, I noted a certain play which is essentially all due to gear play.

I measuread a play of the surface of approx 1 degree, with the servo still - radio on.

I'm very surprised that such a good servo has this play

What are your experiences?

Thanks in advance.

[:o][:o][:o]

RE: Futaba Servo s9650 - gear play
 

I have exactly the same opinion as yours

RE: Futaba Servo s9650 - gear play
 

I have used the Futaba 9650 servos in the stabs of my last two airplanes,and I agree there seems to be a certain looseness in the gears. Yet,I can not detect any tracking problems when flying.
I believe these servos were originally intended for off-road car racing,so maybe that discipline doesn't need the close tolerances???
There are some very good fliers using these.
Chad Northeast,any comments??


Dave

RE: Futaba Servo s9650 - gear play
 

Guys, I have found the problem...

There was some play in the ball links!!! I'm very surprised about that, since I used top quality parts...

So no issues about the Futaba 9650 - sorry for the wrong information. Now I'm happy ;)

RE: Futaba Servo s9650 - gear play
 

Stek79: I would suggest you securely install an arm on a new 9650,then try rotating it directly by hand. Do the same with another new Futaba digital servo (different size) and I will be surprised if you don't find a wee bit of sponginess in the 9650 compared to the other. Even after saying this,I am still going to install the 9650's in my new stab (Black Magic) as I can not see any tracking problems with elevators on my previous two installations. (Giles 202 built from Gator Plans,and a Piedmont Brio)

Dave

RE: Futaba Servo s9650 - gear play
 

How do you guys mount the 9650 with it's weird mounting holes? Do you cut the one off that you are not going to use?

RE: Futaba Servo s9650 - gear play
 

Yes,cut them off with an x-axto type saw. Do not snip them with cutters;you might break the case.
The instructions with the servo mention how to cut them off.

RE: Futaba Servo s9650 - gear play
 

Thanks for the info. I have been using the JR 3421SA. however the 9650 are much less expensive. So I will give them a try this year.

RE: Futaba Servo s9650 - gear play
 

Interesting rgreen, how do you compare these two servos, for example regarding gear play?