pushrod guide tubes
 

How important are pushrod guides? Do you really need the whole tube, or could you get rid of part to prevent binding? I made a stupid mistake and decided to use the pushrods that came with my kit. They make a slight bend through the fuse, and are being held up by the tubes. The surfaces move great, but the last little bit is not returning to center. I want to get rid of part of the tubes, but leave about 2 inches on each side of the bulkheads. I figured I would ask around to make sure I don't do something that will comprimise the safety of my plane.

RE: pushrod guide tubes
 

The guide tubes are designed to provide support. I would not suggest that you remove any of the guide tube material between the bulkheads as this will most certainly give the pushrod room to flex. If the pushrod is binding, you need to find the problem and fix it.

Give them young Marines a hearty OOHRAH for me!:D

RE: pushrod guide tubes
 

Ditto, The guide tube is there to prevent the pushrod from bending. It can't bend if it's hitting the inner walls of the outer tube. Remove a section of the outer tube and the pushrod can bend

RE: pushrod guide tubes
 

One thing you might be able to do if your push rods don't cross is to cross them which usually allows for a straighter run from the servo to the control horn. In other words, the control rod from the left servo will exit the fuse on the right side and vice versa.

DaveB

RE: pushrod guide tubes
 

Make sure your pushrods don't bind before you apply the glue. When all is right be sure you put some bracket in place to keep the tubes from bending. The weight you save by eliminating some of the tubes will be extremely to difficult to measure without a digital scale that reads in micrograms.

RE: pushrod guide tubes
 

The plane I'm building is the gp rv-4. The elevator is whats giving me the trouble. they are split and each half has a separate pushrod. they are linked together near the servo. They are fairly straight until they get into the last few bays. it kinda looks like a stretched out Y. I was also thinking of putting some graphite powder, or some other dry lube in there to help out. The elevators move freely, the problem is when they return to center. The servo stops moving while theres still a little tension on it, and begins to do that little vibrating flutter. I then have to move the servo horn by hand like a fraction of a milimeter. I just want to stop the flutter, any tips?

RE: pushrod guide tubes
 

one other thing I was thinking is to put a slight bend in the rod over the entire lenght. I'm talking a very slight curve.

RE: pushrod guide tubes
 

I am assuming that you are using the inner wire with the spacers, hence the comment about slightly bending the wire. Have you considered using Sullivan plastic pushrods? If you have the option, I would recommend the carbon filled version (black inner tube, white outer tube). The carbon filled version will not expand and contract (overall length) like the other versions offered. Thread in a rod and attach it to your servo. Sullivan even gives you the hardware to make the hook-ups.:D

RE: pushrod guide tubes
 

I'll check that out at the store later. Thanks.