Rudder Stops

[jiott]

Whoops! I trimmed my rudder stops for 25 degrees swing with the called out spacing in the assembly manual. Then I installed the fibreglass fairings (SS7 speedster tail) and discovered that I needed to back the rod end bolts out a little more to get adequate spacing for fabric covering. Only a turn or so on the bolts made a big difference on the rudder swing angle-now its way more than 25 degrees. What is the easiest way to add material back onto the rudder stops? I know John put in threaded stop bolts, but is there an easier way. I don't care about having an adjustable stop. I'm a little leery about just epoxy bonding on a spacer plate-maybe if I also put a rivet thru it? Anybody else have this problem?

Jim

[HighWing]

Jim,
I can't think of a reason that they can't be over 25°. I suspect that the angle given, is a minimum figure i.e., the need to trim. I can think that if the angle is too small that it might be difficult to unlock the tailwheel in a tight turn, but maybe someone else has an idea why 25° is a max. min. ideal.
Lowell

[Dave S]

Jim,

Agree with Lowell - in our case I did the stops to make an adequate clearance between the rudder and elevator - that left me with more like 27 degrees.

The airfoiled tail cannot have as much of a swing as the slab tail - I think the slab tail calls for 30 and I would consider the 25 for the airfoiled tail to be nominal/minimum measurement - if you have the ribs on the rudder and the elevator in place - just swing them to be sure they do not hit anywhere - I left about 3/8" clearance.

For decreasing the swing if you need to in order to prevent rudder-elevator contact consider an "L" shaped metal piece of the correct thickness bonded and secured with one rivet on the side of the "L" which doesn't contact the stop.

[jiott]

Thanks for the suggestions. I agree the main thing is to prevent contact with the elevator-sounds like 27 degrees or so is OK. I will wait until I have the elevator mounted and then make the final adjustment. "L" shaped piece bonded and riveted sounds good to me.

Jim

[jtpitkin06]

Yes I used a bolt and nut on each side for the rudder limiter. I believe it was an AN3-4 with a 365 self locking nut. It was as easy as drilling a hole and installing the bolt. Washers adjusted the head height of the bolt so as to give the proper rudder swing.

You definitely do not want the rudder to hit the elevator. It could get real exciting in a crosswind if the elevator jams against the rudder in the flare.

The nice part of using a bolt is: if after covering the airframe you find a need to make adjustments to rudder throw it's a simple add or subtract a washer.

John Pitkin
Greenville, TX