<June 30, 2006>

Tank Inspection Covers

Tonight I drilled a lot of holes in the inboard tank ribs. I started by drilling the holes for the sender BNC connectors, then I turned my attention to the cover and reinforcing ring.

Following the plans, I drilled the holes in the ribs for the capacitive fuel sender's BNC connectors.

The instructions say to lay the cover on the rib and match-drill the rib thought the holes in the cover. Easy enough, but I wanted to be sure the cover was centered before I drilled, so I outlined it on the rib to check its alignment. It took about three tries, wiping the marker ink off with acetone after each attempt, but I was able to get it right where I wanted it.

Using the lines I drew, I clamped the T-411s back into position and drilled the holes in the ribs clecoing a few of the holes as I went.

Once all the screw holes were drilled, I clamped the reinforcing ring into place and drilled the rivet holes for the nutplates.

To make countersinking of the T-407 easy, I drilled each rivet hole into a piece of scrap wood. The holes in the wood then acted as guides for the pilot of the countersink cutter.

One down, one to go!