In the ARF section the video on building the Strega at 1:38:00 to 1:39:00 is the part I'm questioning.
OK. Depending on the leadout guide material, this might make it wear better, or worse. I have always used delrin for the guide, the Sullivan CD-leadouts straight from the package (which is like a thicker version of the Ukrainian brass-plated carbon steel wire) and have never had a hint of wear on any of them - the plating is still intact, even on the leadouts of the airplane I started flying in 1989.
But, even in the 4 minutes of video I watched looking for this clip, it became very obvious why he might have had a problem with wear - you can't (or at least shouldn't) use the leadout adjustment the way he describes! It is not an arbitrary yaw angle adjuster, it has to work in concert with the rudder adjustment, and in an idealized situation, the leadouts wouldn't even touch the guide, and in a real situation, should only put light pressure on the guide. Anything else, and you are putting consequential torque on the airplane more-or-less all the time, which is going to change as you begin to maneuver. That torque also moves the airplane around in yaw (or roll, for that matter). Of course, it also causes wear somewhere on the airplane, either the leadouts or the guide.
Additionally, taking some oil and wiping it on, you also have any dust or grit that might be flying around stick to the leadouts, which will turn the leadouts into a cable saw. Improper use of the adjustable leadouts as described may well benefit from some lubrication, since the same force you are applying will also tend to induce control binding, which might get better/hunt less with some lube on it. But it is likely to wear out much faster.
Make no mistake, Windy was an *extremely successful* competitor, one of the more successful and skillful pilots in the history of the event, with an enviable contest record - that almost no one reading this will ever achieve. But little things like this open a window into how skilled and determined he was at the handle, because the trim notion he is illustrating is so fundamentally faulty, conceptually mistaken, that if anyone else uses the same idea, they would *never* have much luck without thousands and thousands of flights a year to try to learn how to work around the problem. During which time Paul, David, and Orestes will also do hundred or thousands of flights *without* a handicap to overcome, and wind up far ahead of the game. Which is *why they have been winning everything there is to win, very consistently, for many years/decades now!
If you think this was an aberration, I would guess this video was made in the mid 00's. Windy's real airplanes of the era, like the Testarossa, flew in a manner that is perfectly consistent with trying to control the yaw angle with the leadout guide, IOW, wild (by Walker Flyoff standards) yaw oscillation in in any sort of maneuvering. To make flights of the quality he was making - extremely high by any standard - with the airplane so far out of trim, is a remarkable achievement. I couldn't have done it (and didn't need to...) . It may have been as simple as not knowing how to use the leadout guide/rudder adjustment to adjust the roll/yaw trim. And one small problem is *all it takes* to put you on the wrong foot when you are going up against others.
Note that the method for sealing the hinge lines shown shortly before that is less-than-ideal - it will tend to create the "accordian fold" issue. you want to attach the seal all the way down to the hinge line to both the elevator and the stabilizer, and then cross the gap with the seal right in line with the hinge pins. That way, all you are doing is bending a single thickness of the tape, not compressing and expanding it as you move the controls.
Brett
p.s. by the way, the reason the airplane is more "stable" as he puts it when you have the leadouts back is that a soon as you move the controls, it either yaws the airplane out further (or yaws it in less) than it would have done otherwise. Do that, and the line tension suddenly increases when you move the controls, requiring increased control pressure for a given turn radius. Further foward, this issue is reduced, until you go too far, at which point it will suddenly lighten up on control motion, causing both the loss of line tension, and if you still have *some*, the corner to tighten further due to reduced control pressure. Similar effects happen with excess tipweight, too little tip weight, incorrect rudder offset or Rabe rudder adjustments, basically any trim issue.
It's not just about getting *enough* line tension, it's about getting as near as you can to *constant* line tension so that the control response is consistent. You can use *slight* mal-adjustments to optimize the control response, but these are tiny deviations (1/16" of leadout guide movement, a gram or two of tip weight, (and on my airplane) 1/64" of rudder offset variation. The same effect is why out-of-trim airplanes are so difficult to fly.
Topic: Leadout lube. (Read 2016 times)