Might be good to know what model of plane you are working on. Art
Following, as I want to put in the 5th point on my -4 also. Did you make your own pickup point? And if so, what material is it made from? Did you install the passenger 5th point by wrapping out around the flap weldment?
My plane is an RV-3B, not a -4, and I had no idea what angle the strap would make to the mount. But I did have a length of honking big piano hinge. This was taken before I added rivets to those empty holes.
Dave
David, Not sure what the -3 planes show for the elevator push-pull heim joint (rod end) under the seat, but the -8 and I believe all the others show a an365 Nylock nut, not a castle nut. The reason being that the joint can get torqued and the rotation happens at the ball, not at the bolt.
....As long as the castel nut is pinned, it is at least as good as the self locking nut. That's what their design intent was for; application where a fastener could be subject to rotation....
Not wishing to start a debate and sorry for adding to the drift. As long as the castel nut is pinned, it is at least as good as the self locking nut. That's what their design intent was for; application where a fastener could be subject to rotation. Not unusual for a debate here. I'd guess that a majority of the certified world still specs castellated nuts for applications with (rod end) bearings. If I were to apply such in an area that I couldn't relatively easily inspect/service, I'd probably go castel as well despite the drawing. If all of the cards lined up against you and a lot of time/cycles were involved, the bearing could seize subject the bolt to rotation. Odds are long but they still get beaten.