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Acro-II Control System Question

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Aug 9, 2009
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I am currently building my control system and all the related pushrods.
Does anyone have any insight into why the rearmost pushrod that connects to the elevator horn is such a custom job rather than just continuing the rod-end style used by all the rest of the pushrods?
The forward part of that tube requires a fitting made from sheet that a) captures the rod-end of the next pushrod forward, b) holds a bolt that pivots on the idler arm, and c) is then welded to the pushrod tube. The rearward end uses an insert that is drilled and tapped rather than the AN490 rod ends used in all the other tubes.
Why was the rear idler not made in the same way as the ailoron pushrod idlers in the wing or the idler just behind the seat? It seems inconsistant and I can't see why the somewhat "Rube Goldberg" tube would be used instead of the established pattern of all the other pushrods.
Is t related to the 7/8" tube rather than the 5/8 amd 3/4 tubes elsewhere? or did Paul P just decide to wing it on the rearmost tube? or what?


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