pull pull
 

I am looking at putting a pull pull on the ruder of a plane I am working on but have never use this system can any one give me any help on this. what do I need to do it and the best way etc. Thanks Gary

pull pull
 

Do a search on "pull-pull". There are plenty of good ideas already posted.

pull pull
 

I would suggest you use a ball bearing servo. A bushing servo will growl when you apply tension to the wires. I have pull-pull on my Morris Fun Design. I use Futaba 3001 bb servos. They are cheap and mine have been in service for 2 years (100 to 150 flights) and no problem. Also, if you use wire, hang weights on the wire for a few days before you install it to stretch it out. Try to keep the wires as straight as possible between servo and arm. Also, use at least a double pass on the wire through the sleeve. A triple pass is recommended but the ID of the sleeve is to small.

Another option
 

Another option, instead of using the wire pull-pull is using the sullivan Gold-n-rod like the wire. I am using this on my GP Extra .60 with great success. I am using the "blue/yellow" rod.

It works great, easy to adjust, probably almost as strong as wire, lightweight, and easier to setup than wire. I am a big fan. Depending on the plane, I would recommend a digital servo on the rudder. I have one on the Extra and as soon as I can afford it, most all of my servos will be digital. The one on my Extra is a super fast/high torque and when you snap it up into a knife edge, it stays there, regardless.

Try out the gold=n=rod, it may work for you.

James

pull pull
 

LawDog do you have some pictures? I am currently building the GP extra 300.60 size and want to go the pull-pull route.
I would like to see what it looks like.

pull pull
 

Just wondering, Im not exactly a real "seasoned" builder, what are the advantages of using the pull-pull system over a standard pushrod??

pull pull
 

ramcharger is giving good advice . To Flap: less weight and lots more precise which is the main reason for using.

pull pull
 

Thank you John, I can see the weight difference, just havnt figured how its more precise yet, though I have no doubt your exactly right.
Roger

Here is the process...
 

To put the Sullivan rods in the Extra, here is what you need to do.

1. Get some Sullivan blu/yellow rod.
2. Get a good servo, at least 100+ on the torque, with some speed.
3. Mount servo on hardwood rails in the middle of the fuse. (this assumes that you are using a servo on each elevator half and the throttle servo is mounted farther forward, preferably a mini servo.
4. run the outer portion of the rods just where you would put the grey outer rods on the GP kit (at the bottom closest to the bottom of the rudder.
5. One the epoxy and microballoons dries, cut the outer and sand flush.
6. Get a double horn for the rudder, several people make them, I think mine is a plastic sullivan product
7. fit it to the rudder, making sure that you beef up the rudder where it is going to go. I used 1/16" ply, shaved down the sides of the rudder and glued the ply flush with the rudder, then sanded.
8. when all done covering and stuff, mount the inner portions, golden clevises at the rudder end and 2-56 ball links for the other end.
9. Adjust and tighten, not too tight.
10. finish the plane and go fly.

Any Questions? email me. I have all sorts of tips on this bird. Mine weights a few ounces shy of the bottom weight limit. Good stuff!!!

James

pull pull
 

Thanks LawDog, I am just in the process of starting the fuse. I extended the rudder by 5/8" for more auth. What engine did you go with? I am going to put a Y.S. 61ls in mine-Iwant to keep it light, yet with plenty of power.

Did you cross the rods?