SooprDink

I am building a Kadet LT-40 and I am making it into a tail dragger. I wanted a linkage that went to the rudder to make it steerable but I didnt want it to be a solid shaft from the wheel to the rudder as I saw that as putting a lot of strain on the rudder. The picture shows what I am envisioning however I cannot think of how the linkage between the rudder control rod and the tail wheel arm should be. Is there an easier way to do this? Do I solder some kind of end to the rods to put a type of ball joint on? Any help is greatly appreciated!

Thanks,

Shaun

JNorton

My Feedback: (2)

The tail wheel doesn't have to be at the edge of the fuse as you've shown it. Move the tail wheel until you are 1/2" ahead of the rudder pivot point. The red line in your drawing and connect it with fuel tubing to the tail wheel.

Hope this makes some kind of sense, I'm at work at lunch and do not have access to a scanner.

Edit -> Or use a spring for your connection as shown. Turn the base around!!

John

JNorton

My Feedback: (2)

It was also covered pretty well in this link.
http://www.rcuniverse.com/forum/Kade...1259291/tm.htm

John

JimTrainor

I used this tail gear:

http://www.greathobbies.com/scart/pr...Number=CBA5516

... except I put a small bend in the leaf springs.

It sticks out about an inch behind the rear of the fuse, just under the elevator.

It is (will be) driven using a second push rod from the rudder servo. No direct link to the
rudder. Pull-pull cables to the servo would work well also.

benngrp

My Feedback: (12)

Just finished my LT 40 that I made into a tail dragger as well. What I did was to mount a tail wheel bracket to the end of the fuselage bottom. The trick is to route the control rod/linkage to the opposite side that controls the rudder. In other words, I run the rudder and tail wheel steering off the the same servo. The rudder exits the fuselage as per the plans and the tail wheel steering exits the bottom side of the fuselage on the opposite side. The wire for the tail wheel runs up through the bracket and is them bent about 90 degrees. I wish that I could send you a drawing to make this more illustrative. You have to do it this way (opposite sides) to make the rudder and tail wheel directional. the one thing that you have not addressed is the position of the landing gear. I used a preformed alum. bracket instead of the wire that came with the kit. It provides for a much stronger and less flexible main landing gear. Finally, I hope that you moved your landing gear center forward. A good rule of thumb is to put the main wheel axle about even with the leading edge of the wing. This also helps with moving the CG forward since the aircraft tends to be tail heavy. I'll try and think of some other pit falls.

Good luck

SooprDink

benngrp,
You just stated what I was thinking about all day after my initial post. I had new mains made up and they will be mounted at the leading edge of the wing. I will have a second control rod that comes off the rudder servo and it will exit the opposite side of the rudder and on the bottom. My tail wheel assembly uses a 3\32" rod that I can bend to a 90. Now how do I connect the tail wheel control rod to the 90 that I just bent in the tail wheel rod? Another idea i had was to not bend a 90 but put on a bell crank type of arm on the top of the tail wheel rod. Do they make something like that for 3\32 inch rod? Something like a wheel collar but with a plastic arm that has holes in it like a servo arm. This is my last hurdle... to find out how to connect the control rod from the servo to the 3\32 rod of the tail wheel. Thanks all

Shaun

JNorton

My Feedback: (2)

Everyones postings using external control rods will work just fine.

If you wanted to use your original idea of a torsion rod, you can do it as long as you use a bushing (brass eyelet or tubing) and a soldered washer for a positive stop. The key is to have the pivot point of the tail wheel match the pivot point of the torsion bar as shown. Using a Sullivan tail wheel is the easiest because it comes with the spring.

John

JNorton

My Feedback: (2)

"My tail wheel assembly uses a 3\32" rod that I can bend to a 90. Now how do I connect the tail wheel control rod to the 90 that I just bent in the tail wheel rod? "

To connect a wire to a wire. http://www2.towerhobbies.com/cgi-bin...?&I=LXD919&P=0 Use a strip aileron horn on the 90 degree arm that was bent at the tail wheel. Then use a solder on clevis on the pushrod wire from the servo to connect the two.

John

SooprDink

JNorton,

Thank you for your reply. The diagram you provided made everything much clearer. (I am a visual person) Anyways, later tonight I will work on the plane. Now that I understand how to do it I can make a decision and move on to the next step of the project. I will post and let you know which way I decided to go!! You guys are awesome!

Shaun

benngrp

My Feedback: (12)

JNorton beat me to the answer. I used the strip aileron horn and capped it off with a small wheel collar. I think you will find that the tail will be off the ground on takeoff pretty quick and you will be steering with the rudder anyway. Really just need it to taxi back and forth. Sorry I couldn't send you a picture. Good Luck.

narpets

Or do like the LT25, and use pull-pull from a tiller in the fuse connected to the rudder servo. I used that set up, but didn't use the kit supplied steel cable as I ran my antenna down the inside of the fuse. I used nylon no-streach fishing leader. So far after a year of a lot of use, there is no slop. Works GREAT and is very easy to do.