tail wheel spring question
 

Hey guys,
I'm working on a design for tailwheel spring. What kind of spring constant should it have for best shock absorbtion? Should the tail wheel easily give? Heres a picture of test rig. This setup is for both compression and tension. Thanks in advance. Stoene

RE: tail wheel spring question
 

and here.

RE: tail wheel spring question
 

If you want springs then use springs for the tail wheel via pull/pull cables. You can attach the springs to the tail wheel horns and the pull/pull to the springs. That will give you streering and shock prevention, if that's what your after.

RE: tail wheel spring question
 

Hello Bobh,
Yeah, I started out with that in mind when I built up fuse. I ran the pull pulls back to tailwheel (tiny cable type with plastic sheath). I kept them farily straight but they have lots of friction. I want to use a single servo for both the rudder and tailwheel. The plans show (Brian Taylor 109F) a push rod for controll. I read a forum where some guy linked his tailwheel to the rudder via short rod. I am trying this but have made a small push pull linear spring for damping but didn't know how much give/stiffness was needed in the spring. I'm going to have it asseciable for future maintance if spring is too weak. Heres a pic of work so far.

RE: tail wheel spring question
 

SR,
Run pull-pull with springs to the tail wheel like Bob said and run the pushrod to the rudder from the same servo arm. That's the set up I have in my Brian Taylor SPit. Or you can run another set of pull-pull to the rudder. That way you would keep weight and clutter away from the tail.
JG

RE: tail wheel spring question
 

JG,
The pull pull is the best route for simplicity and weight. I wasn't too thrilled with the linkages, a push-rod with ball on bottom of control horn and shock absorber with ball on top of same horn. That set-up puts alot of strain on the control horn hinge point and I was having to compensate for that and it turns into a slippery slope. The pull-pull is the best but now I'll have to find a way to punch holes in the right places of the sealed fuse to replace the original cables. Thanx for all the infos, Stoene