Carefully trimmed the end of the 408 rib flanges

Tonight I felt brave enough to perform what I call "metal surgery" on the 408 rib flanges. I call it surgery because in essence that is exactly what it is. There are times in this build where you have to apply caution, finesse, and ultimate control over your tools and clamping/securing methods in order to achieve a desired outcome.

I needed to perform precision cutting with my Dremel tool cutoff wheel and be very careful not to let it slip and cut things that should not be cut. After the use of my cutoff wheel, some sandpaper, and a small 1 inch round scotch brite wheel in an electric drill, I think I was successful. From the pics I still need to smooth and shape one of the flanges a bit more, but the other side looks pretty good. Also, in hindsight, I think I may have to remove a bit more material on the flange closest to the rib web, as I remembered that to clear the shop head I need to provide clearance all around the old drill hole. I don't think I accounted for the space closest to the rib web in my measurements. At any rate, enough material was removed from the flange for the hole for the new rivet to be drilled, so I will start there and adjust as necessary.

Here are the top and bottom flanges after the surgery:

the procedure was to use the cutoff wheel to carefully remove only the metal marked off by the cut lines shown in previous posts, then use the scotch brite attachments in the drill to smooth up the cut areas, and then finish smoothing the radiused areas where the old drill holes used to be. I used 220 aluminum oxide sand paper. This is the more expensive stuff, and the ONLY sand paper that you ever want to use on aluminum. DO NOT use regular home-grade sand paper, as the silica in that product can cause corrosion of aluminum. The correct paper can be found at auto stores.

Next up, drilling the new rivet holes in the LE skin. Admittedly this whole thing is a real pain in the butt (and thus the reason why I stopped where I did almost 2 years ago). Had I not decided to do this mod I would have been done with my wings by now. Anywho, no pain, no gain as they say. In the end it will be worth it. Problem is, I have to repeat the entire wing rib mod for the right wing when I get done with this one.

I have been monitoring the stats on my blog for a while now, and I hope that I helping a few other builders out there with various things b providing a bit more detail than you might find on other builder sites. Thanks for visiting.