Can I use a 4-40 fully threaded rod as a direct pushrod from the servo to the aileron on my 4*60? Will it stand up to normal flight loads?

I would not. Just my .02.

You can.. and it will stand up to nrmal flight loads with up to a.61 2-stroke or .72 4-stroke. If you use a larger engine, Don't do the all thread without using Chip Hyde's trick of sleeving it with slip-fit CF tube glued FIRMLY to the all thread rod. (he uses that on 30% size models. See the Pattern forum.)

Actually... (this will get some people going...) If there is NO BEND in the rod... 2-56 all-thread will work on the 4*60 for the ailerons... But once it flexes and bends... its over.

Even worse? (maybe...) 2 mm threaded end rods are what Carl Goldberg ships in the box for use on the Tiger 60 ARF for ALL controls. (those are not as resistant to the initial compression induced bend as the 2-56 all-thread... but they handle the loads better after being flexed.) The Tiger 60 is rated for a larger engine than the Sig 4*60....

Amazing what CAN work isn't it?

I am using 4-40 rods for my 4*60 ailerons. No issues

Rajul: You may have missed the "fully threaded" part??

Thanks 4*60. I am using threaded end and would not recommend fully threaded

Bearcatpilot, what's your reason for wanting to use allthread? Do you get a really good deal on them? Or do you just want to use threaded clevis on both ends?

The kit comes stock with 4-40 pushrods with only threads at one end. Also provided in the kit are clevises that are supposed to be soldered to the rod at the right length. I figured I would just use the fully threaded rod to save me the hassle of soldering. Other than that, there is no reason.

Silver-solder the clevices on. Its ono ofthe best ways to go anyway.

If you use metal clevices bth ends... then the all-thread will freeley spin in the clevices... and can thread itself RIGHT OUT in flight! You'd have to either use a plastic clevice (or like I did.... a Ball-link I used the all-thread on mine.) or use lock-tite on one clevice to prevent losing the ailerons in flight.

Its not hard to silver solder the clevice on... Radio shack sells a paste type silver solder in a syrnge-like tube. (you'll probably use it so little... its not a bad way to get it.) Sand the wire end shiny.. slip the clevice on and heat the thing up. apply the paste and it will wick in the flux then the glund solder will melt and wick in. Works GREAT! This stuff is "match solder" you can heat the things hot enough for it to work with a common wood stick type match. (good for field repairs of soldered landing gear too.) and... MUCH stronger than electrical or plumber's solders.

Thanks for the tip FHHuber. I'll try this before I go with the fully threaded rods.

I'm interestested in trying this solder out... I had a hell of a time getting the solder to stick to my throttle clevis.