Elevator Rod-End Bearing Issue

Trying to install rod-end bearings into my elevator front spars for initial connection to HS. One of the REB's threads into the front spar nut plate about 1.5 - 2 turns and then "let's go". I can't seem to get the REB to screw into nutplate. Given everything is pre- and match-drilled, I THINK I assembled and riveted everything square. So only thing I can think is maybe a little warp in the nutplate.

Don't want to damage either the nutplate or the rod-end bearing. Wondering if there's any advice here on a way to get that threaded end of REB to screw in without damaging either component.

Thanks in advance for your help!

Alignment of holes

That might be caused by the nut plate and the hole in the spar being out of alignment - that is not concentric, so that the threads on the rod end bearing actually contact the aluminum spar hole and get pushed slightly aside and preventing threading in. It should be possible to check by inserting a smooth rod that will just slide inside the threads of the nut plate and then visually inspecting the clearance to the spar hole edges.

Otherwise it may be a faulty or mismatched threaded part that could be checked with an appropriate size tap or die.

PaulvS said:

That might be caused by the nut plate and the hole in the spar being out of alignment - that is not concentric, so that the threads on the rod end bearing actually contact the aluminum spar hole and get pushed slightly aside and preventing threading in. It should be possible to check by inserting a smooth rod that will just slide inside the threads of the nut plate and then visually inspecting the clearance to the spar hole edges.

Otherwise it may be a faulty or mismatched threaded part that could be checked with an appropriate size tap or die.

Click to expand...

Thanks for the thought, Paul. You (with an assist from Mark S on this board who also reached out directly) were exactly correct. Was able to take the barest of shavings of the hole in spar aluminum off with an oversized drill bit, and the REB then got far enough down to grab the nutplate threads.

Thanks, again!