The Murphy Builders Site

Found this gem when I went to debur a part, must have moved after measurement. Suggestions on how to fix this? Hole is only 1.5D from outside edge. I could fabricate a new rib but would rather not if I don’t have to, would need to drive hour each way to use the chapter’s box break. This is a diagonal rib and these are the holes attaching to the trailing edge. Whole assembly gets fabric covered so extra holes are not a cosmetic issue. Only looking at structural.

Well you could put a doubler on the underside to make the area stronger.

You may feel better about it after reading this article. It puts a bit of math into the discussion.

https://www.eaa.org/eaa/news-and-public ... e-distance

At the end he skips quickly over the math but the idea is that for a rivet with a given shear load capacity (force to shear it off) there will be an edge distance (loaded area) in the sheet metal that equals the shear load capacity of the rivet and you get nothing by increasing the edge distance because the rivet fails first and in his calculation that's <1.5D. Per the Q & A on the ACS web site these are Avex rivets.

https://www.aircraftspruce.ca/catalog/h ... rivets.php

Cheers,

Dave
Elite 583

The piece looks to be a channel so some sort; if so, it seems it would be loaded like a beam, in tension on one side and compression on the other. The force on the rivet would be a stretching, not a shear. Craig

This is the trailing edge of a control surface, kind like this:

The math sounds good but it is a straight rib so it is relatively easy to fabricate a new one that is a hair longer.

Yes, almost every part in your kit can be made with a hammer, brake, and some aluminum. A router with a pattern bit, some mdf, and a spindle sander are also helpful. Glad you got it figured out!