I was trying to figure out just where to post this as it can happen to any of our designs so I stuck it in this Safety Forum.
While getting my wings ready to cover I was fiddling around with the aileron linkage and just screwed a bunch of random rod end onto the push rods to check travels. The aileron bellcrank in one wing was somewhat limited for no immediately apparent reason. Closer inspection revealed that the random rod end I had screwed onto the push rod was not the Heim that I typically use. The body on the rod end in question was larger and did not saddle into the bellcrank lever as the Heim rod end did. So I am thinking what could happen if someone had to replace a rod end and could not get the exact same one that the airplane was built with. This rod end has the same mechanical description as the Heim but it is not the same. Had this been installed on a flying airplane it could have resulted in a bent threaded rod end(the insert in the tube) and that can become a potential failure point.
In the first photo you can see that the lever on the bell crank will travel all the way to the screw/nut plate on the spar. The second photo shows how much the travel is limited by the problem rod end. The other photos show where the problem rod end bound in the aileron bellcrank lever. You can see the damage on the problem rod end. If you change out a rod end make sure it is a proper replacement.
While getting my wings ready to cover I was fiddling around with the aileron linkage and just screwed a bunch of random rod end onto the push rods to check travels. The aileron bellcrank in one wing was somewhat limited for no immediately apparent reason. Closer inspection revealed that the random rod end I had screwed onto the push rod was not the Heim that I typically use. The body on the rod end in question was larger and did not saddle into the bellcrank lever as the Heim rod end did. So I am thinking what could happen if someone had to replace a rod end and could not get the exact same one that the airplane was built with. This rod end has the same mechanical description as the Heim but it is not the same. Had this been installed on a flying airplane it could have resulted in a bent threaded rod end(the insert in the tube) and that can become a potential failure point.
In the first photo you can see that the lever on the bell crank will travel all the way to the screw/nut plate on the spar. The second photo shows how much the travel is limited by the problem rod end. The other photos show where the problem rod end bound in the aileron bellcrank lever. You can see the damage on the problem rod end. If you change out a rod end make sure it is a proper replacement.
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