Brief Description: Rivet Nutplates on Top Right Flange
I used the hand squeezer to rivet the nutplates along the top right flange. I had a question regarding why the Plan's called for using the countersunk nutplates rather than the flat nutplates since the flanges are countersunk rather than dimpled. In other words, the inner face of the flanges is flat. I posted this question to the RV-List on the Internet and several people indicated that the countersinks for the #8 screws were so deep that a portion of the dimpled skin would portrude below the inner surface of the flanges and consequently the countersunk version of nutplates were needed. This didn't make muck sense to me since the countersinks for my #8 screws weren't that deep. Then I realized that the sample dimple that I was using to set the depth of the countersinks was too thin. The skins are actually much thicker. I created a new sample dimple using a scrap piece of aluminum sheet that matched the thickness of the skins. When I test fitted this into my #8 countersunk holes, I found I had to countersink these much deeper to accommodate the the dimple in the thicker material. I'm glad I found this out now. I went through all the #8 screw holes again with the deeper setting. The countersunk version of nutplates now make sense to me. Also, this served to remove any oblong holes that may have been on my top flanges that resulted from not initially using the nutplates themselves as the guide for the pilot on the countersink bit. It all worked out fine in the end. Just ended up spending more time on this than had I followed Van's directions to begin with and had I realized my sample dimple was in too thin of material. Great learning experience.
