pull pull simplified?
 

I was in Graves Hobbies in Orlando on Sat. and they had rudder horns that were made for pull pull. It had a piece that wraps around the leading edge to put both exactly equal. As you know, equal distances and holes lined up exactly with the hinge line means perfect pull pull (both stay tight thru full movement without needing stretching.) Seems like these on the rudder and elevator would be dead easy to make the perfect pull pull. Unfortunately, I do not know who makes them, I'll have to look next time I get up there.
Tom onrecess PB#143

pull pull simplified?
 

I have looking for the same part myself but never found one. I currently have that setup one of my 3Ds. I got the peice from a Tatoone spring tail landing gear set. I don't think it's being sold seperately.

Maybe this will work.....
 

I found this in the Tower Hobby book on page 91 ( 2003 wish book ). I've also seen what you are looking for. I think Sullivan makes it....

Best regards,
Mike

horns
 

Yeah, that's it. Just the horn part. Like I said, Graves in Orlando has them, I can get them next time I'm up there. I thought they would be a help to others if we could post who makes them. I wish I had them when I put my Knife together!
thanks,
Tom onrecess PB#143

pull pull simplified?
 

I think tower has just the horn part listed under stock #LXA394 thru LXA397
(for different widths). By the way can anyone help me with how to set up a pull-pull and what I need to get(beside the horns), Ive never done it befor but got a new Edge for x-mas and want to try it. Thanks. Randy

pull pull simplified?
 

This is by far the best pull-pull and elevator setup I've seen. I learn this setup from a Free Style 3D from Global I'd recently gotten. From the diagram, as you can see, the rudder servo is right on the center line of the plane. Also, the travel of the elevator servo horn is on the center line of the plane. The rudder cable cannot hit either the throttle or/and elevator servo because it rises above them via the rising blocks.

Since I ran the entenna inside the plane, I did not use the metalic pull-pull cable that came with the plane. Instead, I used the Sulivan kevlar cable setup that I bought from Tower. It's about $10. Part # LXFV28.

$10 is a bit expensive for one setup. For my future planes, I would just buy a spool of kevlar ($2.50 for 100') and 2-56 loop-hooks from Home Depot and build similar system.

setup pull pull
 

I cannot be of a lot of help as I have set up only one. Dubro sells a pull pull kit with everything. One note to remember is to make sure the geometry of the servo arms and horns are the same. If the servo horn arms have a little number next to them they are off by that many degrees. Same thing with the horns, (which is why these work so well), they must be right on the hinge line and exactly the same. If the geometry is off, even a tiny bit, you will get slack in a cable when the surface is deflected (then comes flutter...)
Tom onrecess PB#143

pull pull simplified?
 

The double horns are made by C.B. Associates. My LHS has 3 0r 4 different sizes.

pull pull simplified?
 

The only thing you need to do is measure the thickness of the surface where they will be mounted and find the closest size horn to fit. They work great and have been around for many years.

JW

pull pull simplified?
 

I have done my fair share of pull-pull systems and i have never had a problem if one cable goes slack when the other is pulling the control surface...in fact i offset my horns aft of the center line to gain control surface movement and it increases the leverage of the sytem and therfore takes less power to run a 5 inch aileron up to aprox. 75-80 degrees of one direction of travel. Yes the cable that is not pulling the surface goes slack but the airflow is pressing against the surface and against the pulling cable.
Another trick we have learned is to eliminate the crimp on type cable locks which can easily be crimped on to hard and cut the cable and eventually the cable will break. Loop the cable thru your horn and wrap it about 3 to 4 turns back up the cable running from the servo and then melt the plastic coating from both cables now together with a lighter or small torch. Never had a problem with the cable breaking then.

pull pull simplified?
 

Where do you buy a spool of kevlar?

Also wondering where someone could get the the guide tubes (like the ones that come with the Morris planes).

If I could figure where to get those I could a chunk of cash with each plane!

Thanks in advance.

Pull pull
 

You can buy the housing from NAPA. It is used for oil pressure lines, or something like that. Tom

Kevlar
 

Go to a good sporting goods store, even Walmart. Fishing line called Spiderwire is kevlar. Many different strengths. I last bought 80 lb test which has a 15 lb diameter(meaning the same dia as 15 lb nylon fishing line). If you want to use a plastic coated metal pull-pull try leader fishing line in a 20 lb test. Also at Walmart. While your there you can also buy the pliers used to crimp fishing leaders along with the crimping sleeves. The pliers will crimp the sleeve the proper amount. Then the only thing left to get for the pull-pull are the 2-56 threaded ends by DuBro; # DUB201. 4-40 Dubro # DUB618. I now have enough for several airplanes.

Don't forget to put a drop of thin CA on the kevlar crimps when finished.

Tom...