Brief Description: Drill Access Ring to Inboard Rib
There is a small tooling hole at the root of the inboard rib that is supposed to be covered by the access ring / access plate that I didn't notice until after I had drilled the access hole in the inboard rib. Unfortunately, only about 3/4 of the tooling hole was being covered by where I positioned the ring and plate. I tried to think of the best way of handling this - just prosealing the sucker closed, adding another small cover plate, or repositioning the access ring / plate slightly more towards the root to cover the hole. I decided on the last option. I didn't want to rely just on proseal sealing this hole without any aluminum in the mix and a small cover plate was not an option based on how close the nutplate holes were to the tooling hole. Sliding the ring and plate toward the root slightly did not cause any edge distance problems for the screws/nutplates and simply meant the large hole would be slightly oblong. Once I had the ring and plate positioned to cover the tooling hole and had everything clamped in place, I drilled the screw holes using the holes in the plate and ring as a guide. Then I drilled the holes for the nutplates using the holes in the ring as a guide. The ring and plate only had to be slid off center about 1/16" so everything is fine. I will use the die grinder scotchbrite wheel to smooth out and align the access hole in the rib to the slightly off-center ring. Once the rib was drilled, I drilled the reinforcement ring to some wood and then countersunk all of the rivet holes using the wood as a guide for the pilot on the countersink bit.
Access ring and plate clamped to rib - ready for drilling
Access ring and plate clamped to rib - ready for drilling
Countersinking reinforcement ring for the tank access hole
