Newbie Question - Flexible Pushrods

I have just finished building an Eagle 2 trainer and I'm ready to install the servos, receiver, push rods, etc.

My question is this --- the plans call for a 1/16" dia. pushrod for controlling the throttle and the nose gear. Both push rods are supposed to run through nylon guide tubes (probably because both of these particular push rods need to bend a fair amount). Is it better to go with the flexible type of push rods that are more like the cables on a bike? Its an added expense, but it would seem to me that they would be easier to install and not put as much load on the servos (which also means the battery won't be 'working' as hard.

Any suggestions?

Thanks

Don Tanner Oakville, Ontario

Reply to
Don Tanner
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Sure. Just use a Quick Connector on both ends and the adjustment becomes a breeze. Make sure you solidly anchor both ends of the nylon tube, or things will never have a reasonably adjustable geometry.

Reply to
Six_O'Clock_High

Reply to
Bob Bauer

Every version of the Eagle has had the same problem. Cheap design, but it does work.

None of the solid wire push rods flex well at all.

The real issue on the nose gear is that the arm is so short it requires a goodly bit of lateral travel by the push rod, and the exit "wound" in the lower fire wall winds up being a slot rather than a hole. Connecting both rudder and nose wheel to a single servo is APITA as well.

A better albeit more expensive approach is to install a nose gear servo and a rudder servo and drive them off one channel via a "Y" cable.

You can use the lightest Sullivan S507 braided steel cable for the throttle, just be sure you use nylon fittings on the engine end.

The nose steering will need a heavier Golden Rod.

See the "Pushrod Application Guide" at

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Fred McClellan The House Of Balsa Dust
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Reply to
Fred McClellan

Be sure you do NOT use metal to metal connection at the throttle arm (engine) If the throttle arm is plastic, then just use a z bend. If it is metal, you will need to solder on a threaded coupler and use a nylon quick link or nylon ball link.

Reply to
jeboba

I always try to use a metal pushrod for the throttle. After I was done flying one day, I noticed that my plastic throttle pushrod was melted half way through! More work...less worry!

Don

Reply to
Don and Marion

Nothing wrong with a metal push rod on the throttle. I use the Sullivan braided variety all the time, even on gassers.

RF issues can arise when the connection to the throttle arm itself is metal, so the experience of many suggests using a nylon clevis or at least a nylon/plastic ball joint to insulate the metal push rod from the throttle arm, and thereby avoiding metal-to-metal induced RFI.

Cheers, Fred McClellan The House Of Balsa Dust

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Reply to
Fred McClellan

Thanks to everyone who responded to my question --- you were very helpful.

Don Tanner Oakville, Ontario

Reply to
Don Tanner

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