Throttle Sleeve, ACE OR COX Setup??

astronomer1 Sun Jan 08, 2012 7:04 am

I am building an ACE Whizard using a Dickybird TD.049 engine
that is working very nicely. 5.5K to 18K RPM. I am having a problem
with the servo pushrod binding whether I use a Z-bend or a small nylon clevis
with fuel line keeper. On the test stand, I’m using a piece of .032 safety wire
and actuating it by hand and it wants to bend. I want to use ridged
piano wire with the servo.
What is the most effective way of hooking up a servo pushrod
to an ACE or COX throttle ring? I have tried using Z-bent piano wire keeping the Z-bend tang as short as possible but it still binds with the throttle ring and the pushrod wants to fall off. The small Nylon clevis with fuel line keeper, binds either at the fuel line keeper part or the end of the clevis where I have filed it shorter in an attempt to eliminate binding. I am afraid to file more for fear of further weakening it.

nitroairplane Sun Jan 08, 2012 7:06 am

Okay I would try making the piano wire diameter a little smaller and adding some oil to it.
That should help a bit.

microflitedude Sun Jan 08, 2012 7:36 am

I have made an assembly which I think works excellent.

I use the pushrod/sleeve out of this park flier ~

http://secure.hobbyzone.com/hobbyzone/hobbyzone_mini_super_cub_parts/HBZ4885.html

Unfortunately, they do not sell them individually. But Du-Bro also makes some, which should work. One end has a Z-bend, the other straight. Cut that end to size, then cut a little off the sleeve to allow for the servo arm. Use an anchor in the servo that has a small thumbscrew to mesh on the pushrod. Tighten it good and use thread locker. Make sure the push rod sleeve is secured in at least on place on the airplane.

It works great. The wire is small enough to fit in the hole on the sleeve, and bend around the sleeve a little if need be. But will not bend in the sleeve if secured.

http://shop.dubro.com/products/productdetail/30%22+Mini+Pushrod+System+.062%22/part_number=941/101.0.1.1.5161.5165.0.0.0?pp=12&

"Ideal for 1/2a aircraft..."