rffs-100 help

[muskrat]

could someone please help me. I purchased a rffs-100 system at Toledo last Friday. I built the Skeeter model from the included plans. I have the system all installed but I get very little movement from the rudder or elevator, the throttle works fine. How much travel should I be getting?
My other question is, is this system supposed to make all these noises or is something hooked up wrong? Any help would be greatly appreciated.

[gjohnson]

Yes it is supposed to make that noise. As I understand things it's a byproduct of the "pulsing" that makes these proportional. The single biggest problem that people post about is not getting enough movement from the control surface. This seems in each case to be related to CA wicking its way to the middle part of the hinge and hardening the rubber. It doesn't take much. I use medium CA, apply it with a toothpick or piece of piano wire. I only apply it at the ends and let it wick partway back. This means the hinge moves and is not completely immobile for the entire slot. This insures the rubber is free to flex.

I just hooked one up today and you can see a picture of it on my site under the Fokker D-VII page. I used the same technique on my Stechmücke floater. I hope this helps.

Basically:
(1) use medium CA
(2) apply sparingly far away from the middle of the hinge,
(3) test it before installing the rudder or elevator on the plane.
(4) glue coil to elevator or rudder with ambroid glue, not CA (thanks to Dave Robelen for this one) so it can be removed with acetone later if needed.

http://home.attbi.com/~gordonjohnson/

[muskrat]

thanks G,
I'm going to cut the old rubber out and try it again. The surfaces sure seem to move freely, but the rubber is hard in the middle. I glued my coils on using silicon. I'll let you know how it worked.
jim

[rkissin]

You can also try stretching the rubber band very gently, or nicking it with an Xacto. Had the same problem, worked for me.