A Dubro 2-56 rod was installed into the retract unit just as the mains were. The rod was then connected to the HS-81MG and tested.
I planned on using a single servo to turn the rudder as well as steer the nose wheel. Unfortunately the existing micro servo I had in the plane would not handle both jobs so I chose to use the old nose wheel steering servo (HS-81) to run the nose wheel and rudder. I had to widen the servo bay a little to fit the HS-81.
To connect the rudder servo to the nose wheel I would employ a Sullivan Gold-N-Cable control rod set (Cat #507). The 0.032” diameter cable push rod system is very light and can slink around the fuse without any problems.
I silver soldered a 2-56 threaded end on the cable using some high quality silver solder and acid flux.
A support block would be needed to hold the cable liner at the nose wheel side of the push rod system. I made a 50 X 15 mm long block out of balsa and drilled it with a 3/32” drill bit down the center. Thick CA was then used to glue the end of the cable liner into the support block.
I ran the push rod cable from the servo over the top of the fuse and dropped down into the battery bay along side the battery plate. A small hole was then needed in the foam side of the fuse alongside the retract servo to accommodate the control cable as seen below.
To glue the support block to the fuse I used 5 minute epoxy and microballoons. I aligned the control cable with the steering arm making sure that I left enough clearance for the steering arm to move both directions.
The clevis was attached to the steering arm and tested in both gear up and down positions. Notice that the clevis can move back and forth freely when the gear is up. This is important or the rudder will bind when the gear is retracted.
I fabricated a cable support out of 3/8” balsa to support the servo side of the push rod cable as seen below.
Not much was left to do but install the wing and test out the gear. I installed the flight battery and cycled the gear a few times to check for binding. I synchronized the nose wheel steering to match the rudder deflection by adjusting the clevis on the rudder.
The airliner really cleaned up with the gear tucked away. By now I was excited to fly this magnificent foamie :0) I still needed to check the CG and see how much weight the whole conversion cost me. With the battery already installed I placed the jet on my digital scale and weighed her in at 3 pounds 13.75 ounces which is a difference of exactly 4 ounces from the original weigh in. To me that more than acceptable considering I added three retract units and two servos!!! Overall the 4 ounces represents a increase of only 7% to the total weight of the aircraft. I loaded up the airliner on the CG machine and was pleasantly surprised to be at about 136 mm from the leading edge. That’s only 2 mm forward from where I started.
I placed an 1/8 oz lead tab on the very tail and I was able to get back to 138 mm. I cut a pocket in the foam and pressed the lead weight into foam. Later I patched the hole with NHP Micro Fill and touched up the paint (not shown).
