Have both wings completed on my sig se, and have started planning fuselage construction. Plan to use metal rods for rudder and elevator inside the supplied plastic tubes. Have seen a thread somewhere that you could cut 1/4 inch pieces of the inner nylon rod, slip them over the 2-56 metal rods, spaced about 3 or 4 inches apart to reduce play. Have any of you had any experience with this modification? [&:][&:][&:]

A lot of Great Planes kits use this system for push rods and I have built several models with these types of push rod. They work really well, but make sure you don't have too much curve in the outer tube, and support the tube at every former it passes through. I space the little pieces of inner tubing at 2" apart on the rod. Good luck and have fun.
Bill.

Ditto could'nt have said it better

Well, I simply replaced the plastic inner pushrod with a DuBro one-piece metal rod cut to length, a solder clevis on the servo end and a threaded metal clevis at the control surface.

I tried that spacer business on a Super Sportster MK II I built a couple of years ago. The outer tubes were a straight shot, and I still got some binding. Not much, but enough to cause me to trash that pushrod and use just the wire.

You don't need those spacers. The theory is sound, but in practice simply not necessary, IMO. The outer tube serves as a guide only; 2-56 rods are plenty stout enough to handle the loads on a 40-size model, just needing a bit of support in a few places to prevent bending. The outer tube does that.

I did pretty much what Steve has indicated. I simply took 2-56 rods and slipped them in the outer shell. I haven't had any problems with binding and the sleeve provides plenty of support. I have a 4*60 in which I had originally used the nyrods, and just couldn't keep the thing trimmed as the temperature changed. So I replaced them as well.

I did the same for my 2 SE's. Just used metal rod inside of suplied plastic and its fine. I just took them to HS to make sure I got right size.

Ditto, I use full length steel rods slipped inside the tubes in the arf version I had. Didn't need any "spacers", worked fine.

make sure you rough up the surface so the solder on clevis and threaded end stick and don't come lose under vibration.

I tried Sullivan flexible rods on my second SE as I was not too happy with the ones in the kit.

Problem was that the length beyond the tube was too long and the rod flexed when I didn't want it to[&o]

I solved this by soldering a section of 2-56 to the flexible rod just past the point it emerges from the tube (allowing for movement of course), using some brass rod as a sleeve. Seems to be working OK so far.


Terry

Ya think 220 garnet paper is sufficient???