I am currently building a GP Aeromaster 60 size. Where the rudder and elevator pushrods exit the fuse, there is an unsupported length of about 4-6" (going by memory) before they reach the horns. I wanted to use Sullivan Gold-N-Rods, likely the semi-flexible (blue tubes) and I was wondering if these can span that type of length.

Do I have to change to a .072 wire just as the pushrod exits the fuse, or can I run the plastic pushrod out closer to the clevis before putting a shorter section of all-thread in the end to connect the clevis to?

Run a metal wire from the fuse to the control horn

Thanks Mike. I was pretty sure option #1 was not so swell. I did not really think of #3, but it is not as easy on the eyes as #1 anyway. The part I was struggling withwas the CA end. I did not know if I was going to have to break out a #2-56 die, but certainly did not want to!

BTW, I got this Aeromaster 60 and the US 60 around the same time; I decided since I have not built anything in a few years (about 25), I would practice on the biplane since I really want the US to be perfect.

I got about 1/3 of the way through the fuse over Memorial Day weekend. I probably won't do an all out build thread, but I will post some build pictures soon.</p>

Clean the end of the rod with sandpaper both to clean it and the score the surface to give the CA something to hold on to.

I usually do option 3 with a longer rod threaed at both ends. Are you saying that a non threaded rod with CA strong enough for elevator on a 60 size plane?

As long as you have more than an inch or so glued inside the tube it will hold up.

Test it yourself. Clean a rod, CA it into a piece of inner nyrod tube (be fair and give it plenty of time to cure) and try pulling it out.

I have had retracts attached like this and in a crash the nyrod broke before the glue joint.

Personally, I would NOT go with option 2. I would go with a modified version of option 3. Use a length of 2-56 or 4-40 rod (whichever fits your application) that is threaded on the end. Cut it long enough to insert into the plastic tube beyond the unsupported area and simply thread it into the tube from the backside of the threads...I hope this makes sense! This way, you could even go with option 1 as long as the metal rod inside the tube extends beyond where the yellow enters the red tube..

-Johnny-

I like option 2 as long as the unsupported length does not get too long, as you say.  If the semi-rigid (blue tube), rather than flexible (red tube) Gold-N-Rod (or the Du-bro equivalent) is used, I am sure there is tolerance for a modest unsupported length.  We are talking about a 60 size plane here...

My goal though would be to trim the tube flush with the fuselage and have the plastic rod cut to a length that maybe sticks out of the fuse 1/4-1/2" or so.  The yellow rod is more noticeable against my planned white fuse than the metal pushrod that will be on the outside.  I was actually thinking that I could bury the plastic completely and let the metal rod go into the tube, but that may be a bit obsessive.

To me that looks and will function better.  As Mike said, the plastic would likely fail before the glue joint if the surfaces are properly prepared.  If you scuff up and then clean two surfaces with IPA before using CA, they can be VERY hard to get apart after a few hours of time.

Like JRBMOTO, I just take a rod that is threaded on one end. Insert the non threaded end into the tube end thread it half way. This leaves half of the threads to put a clevis on. The rod can be cut to any length and will support the exposed section. It may be overkill compared to Minn's diagram, but the metal section of the rod will be in past the bulkhead doing it this way.

David

Sorry Mike but I just cant trust a glue joint alone without some kind of mechanical backup...Threading into the plastic inner rod, in my opinion, is a much safer option. Thank you daveopam for your input, you definitely know what I am talking about and did a good job explaining things

-Johnny-

rickbrad, I do mine like MinnFlyer but use epoxy. Force a few drops in the tube with your push rod, spin it around to get it wet all the way. I try to get it in about 4 inches. I do this at both ends so I can use Z bends at the servos. If you don't want to see the ugly yellow tube, cut it so at max push it stops at the fuse edge. Also put a pinhole in the tube some where for a vent. I have some of these that are about 20 years old and you still cannot separate them.
Thanks Minnflyer, I never considered using CA. Think I'll give it a try.
Scott

Good suggestion Dave. I revised the illustration

Thanks for the props guys. We all get lucky every now and then.

David