Posted 10 Mar 2017 I found a significant crack in the 5/16 thread on the top of my one lift strut. The end consists of a AN490HT 11P rod end welded around the periphery and rosette welded into a 3/4 inch x .035 tube. I doubt that I could remove the old fitting without wrecking the strut. So I carefully cut off the old threads and filed the end flat. I center drilled the end and slowly drilled it out 1/64 at a time until I came to solid metal. Turns out the I.D. of the AN490 fitting is 1/2 inch. I threaded it 9/16 National Fine, and was able to get a little over 1 inch of thread. I then made a threaded bushing 1 inch long x 9/16 o.d. with a 5/16 inside thread. Into this I inserted a 5/16 x 2 inch stud. I loc-tited the whole thing in place.Even a grade 2 5/16 bolt has a minimum tensile strength of 3900 pounds , and I used grade 5 at 6300 minimum. The O.D. of the AN490 is .679, giving a wall thickness of .089 at the peak of the inside threads. Maybe not the best fix but certainly the easiest.Give anybody heartburn?Bob McCaa Share this post Link to post Share on other sites
Posted 10 Mar 2017 Your solution should be fine. When I first got my bird one of the ends was bent and I did not like the idea of straightening it so I drilled out the rosette weld and carefully ground around the top weld of the fitting. I got a new one from AC Spruce I think and welded it back it. All in all it took less than an hour start to finish on replacing the threaded end (less painting). Share this post Link to post Share on other sites
Posted 10 Mar 2017 If I understand both of you correctly, you are using AN Female rod ends to attach to the threaded end sticking out of the struts.I went the other way when building my struts. I welded in some inserts with a 3/8 - 24 threaded hole and used AN male rod ends to thread into the hole. I figured the AN male rod ends are a lot stronger than Grade 5 bolts or threaded rod. EDMO 2 people like this Share this post Link to post Share on other sites
Posted 10 Mar 2017 The fittings I bought were machined with rolled threads not cut and were made for this purpose. Share this post Link to post Share on other sites
Posted 10 Mar 2017 Yea, the fitting is AN490-HT11P Question was: I did not know if the fitting was rosette welded in two places, one of which was under the cross brace. Had it been a straight piece of tubing I'd have put it in the lathe and machined it out, but to try that by hand on something as thin as .035 tubing and risk going off center and then trying to drill and weld through an old weld didn't appeal to me. I could have used a 3/8 male threaded rod end into the plug, and bushed the bearing end down I guess. Might try that if it will fit the wing attach point. . That would make the bushing a bit less than .125 wall thickness, but that is not where the concern is. The concern would be where the old stub is welded in. As it stands, that wall thickness is .089 at the peak of the threads. Share this post Link to post Share on other sites
Posted 10 Mar 2017 I went to the 4130 female threaded inserts while building completely new 1" x .058 wall struts - I know that the 5/16 x 1/4 rod ends are used on all AvidFoxes up to and including the Magnum - But I had 3/8 x 5/16 male rod ends on hand, so I used them - had to modify my strut attach fittings because there was not enough clearance for the larger rod ends. EDMO Share this post Link to post Share on other sites
