jldecarlo

I am putting floats on a Sig LT-40. I have balsa covered foam floats about ready to go and I want to add a water rudder.

What is the easiest (not prettiest) way to rig it? Pull-pull or Ny-rod? If I go pull-pull, I will need pulleys - which ones do you recommend?

Do I need dual rudders, or is one enough?

Thanks,

Leonard

seaplane

Leonard, I used a nyrod on my wife's LT-40. Connect it to the rudder horn and loop it back to the water rudder. Anchor the nyrod at both ends and away you go.

Oregon Craig

I had a Sullivan flex cable all hooked up, but I didn't like it. Way too much slop. I was sitting in the bathroom (really!) looking at the Dubro catalog, and in the car section, I saw ball links. IDEA!

I got 2 ball links, a couple of scrap pieces of rod with 2-56 threads on one end, and went to work.

I put the ball links on the 2 threaded ends, attached them to a seperate control horn on the "air" rudder, and to the water rudder (Ernst brand). Centered everything, marked the 2 rods, and made them into one rod by cutting them and soldering them into one rod. I shined the joint up with fine sandpaper, wrapped it with fine copper wire, and silver soldered it.

Now, my water rudder has no "dead-zone" in the middle, follows the air rudder pefectly, and centers properly. None of this was true with that long sloppy cable.

Never tried Ny-Rod, but that may have been better than a cable, no doubt. I really like my method, and hit my head on the wall a few times for not thinking of it sooner. Oh well, I only have 10 little holes in the side of my fuse to patch [sm=spinnyeyes.gif]

I will try and remember to add a picture of it to this thread tonight.

Craig - N7OR

4*60

My Feedback: (41)

Other option is stick plastic tubing through nose wheel spring and add monofilament through it to the rudder arms. Then CA the line to the plastic in the nose wheel and the water rudder will do whatever the nosewheel did and if the plastic tubing is longer it will travel more, which is good.

Oregon Craig

Here it is. Not a great pic, sorry.
This is really simple and works good.

jldecarlo

Thanks for the pic, it helps your written discription alot.

However, the LT-40 doesn't have a split elevator like your model. The rudder is only above the stab and elevator. I think your method would work well with a second servo.

Leonard

JimCasey

My Feedback: (1)

You don't need pulleys for pullpulls. Small pieces of nylon rod work ok, but I have had complete success with dubro 2-56 eyebolts, and Power-Pro fishing line. Power-pro has NO stretch and is hideously strong. You don't have to use crimp sleeves on it either. I have never seen a nyrod water rudder setup from the rudder horn to the water rudder that looked adequate.

If you don't use pullpulls, just mount a tailwheel bracket and drop a flag-shaped water rudder down from the tailwheel position.

flipstart

Followed Craig's idea and added a pushrod from rudder horn down to the water rudder horn using ball links for hookup-works ok-still would prefer pull/pull-my setup does not seem that positive for return to center but I am using dual rudders with pushrod running in between. Seems like a lot of load on one servo. Any more comments from you pros before the grand finale!!

Goinstraightup

My Feedback: (26)

For some planes you can get away without a water rudder. I think in your case it will be best to have one. My .60 size Cloud Dancer was OK without one. On my Kadet MKII I made a post in the fuse out of a 1/4 inch dowel. The post had a servo control horn on the top, and stuck out of the bottom of the fuse about 1/2 inch and had a servo arm on that end too. I had a balsa bracket in the fuse with a hole in it to hold the dowel where I wanted it. Then I just made a pushrod from the bottom of the servo arm on the dowel to the water rudder and a pushrod in the plane from the rudder servo to the servo arm on the dowel. Worked great and all I had to do to go to wheel flying was unhook the pushrod from the servo arm on the dowel (as well as remove the floats).

mscic-RCU

My Feedback: (6)

I mounted a watertight servo in the top of the float. I slaved it to the air rudder and mixed it to switch on transmitter so I can turn it off when the plane is up on shore. Works great!