I'm building ( ARF) my second plane, and it asks to solder clevises to rod. I didn't do this on my first ( different system, clevis had tread as well as pushrod). What's the reasoning behind this ? Anyone? Why not just using tread ?</p>

Its an option, adjustabilty at both ends can be handy, or a bother. I'll bet the included clevises (clevii ?) are not threaded. If threaded be sure there is some method to prevent unwanted turning such as a lock nut.

On some applications the plane might require a "fixed" non moveable linkage point. In order to do this they want you to solder the clevis on so it can not move in or out and locks the control surface in place. On the other hand what you described with the clevis that has internal threads that screws onto a rod that has threads on it, is another type of linkage that allows you to adjust the position of your control surface. You can twist the clevis in or out which will make your control surface move up or down.

The only time I solder a clevis to a control rod is in tight spaces that will be sealed off with no access later. The tail section of Top Flites Cessna 182 is a good example, all control rods for the tail section are internal and once the plane is complete future access is difficult at best. In those situations a strong, permanent bond is desirable.

@ OzMo: you are right, clevises not treades, just smooth inside.

@davidgeorge212: The treaded clevises were on my 1st. plane (Hobbistar 60 MK III), anyway original clevises were swaped for treaded Sullivan black plastic clevises with lock. These not treaded clevises that we are talking about are for a Super Sportster 120. I really don't see the point of the soldering, beingthatthe clevis cannot turn on the rod,as is hooked in the servo arm. Of course , I can be wrong.

@skylane_182: The pushrod are outside the fuselage, plane is a super sportster. Again , your post agrees with my idea of not soldering pushrod/clevis.

Thanks to all three responses.

Juan

It doesnt matter to much which way you go with pushrod attachments, but you should probably have one side that is fixed and one side that is adjustable. With a solder clevis that would be your fixed point so on the other end of the push rod you would need something like an E-Z link that would allow you to slide the push rod back and forth and lock it in just the right spot.

Nylon and Metal Clevises for Model Aircraft:

http://www.airfieldmodels.com/inform...l_clevises.htm