RE: pull pull help
Like Airborne 2007 said.
I have pull-pull on my 3DX and it works good. I used it on elevator and rudder. On ailerons I used push rods. Takes a little longer than pushrods but is lighter.
Use a string that doesn't stretch. Unwaxed dental floss works. Some kinds of braided fishing lines work too, like Spiderwire.
A really really long piece might stretch, but in the length you would need it doesn't.
I tied one end off at the the control horn, then used a Dubro Micro quick connector to slide a small piece of wire that I bent a loop in. Slide the wire half way into the connector then tie the line to the loop in the wire. This way the lines can be adjusted. I've heard of people using a sewing needle or small cotter pin in place of the small music wire I used. Do this on each side of the control surface and servo. Use the double arm servo horn.