Tue Jun 10 2008

Drilling F-715s and deburring extra F-716 ribs

This evening I decided to drill the F-715 ribs to the floor plates. I first clecoed them in place.

Then I used some of the NIB magnets my brother, Chris, had given me to hold the flange of the rib in position while I drilled through the floor plates. The instructions say to let the web of the rib stick outboard about 1/32 of an inch past the edge of the floor plates. I didn't measure that...just eyeballed it and it came out fine except near the aft ends of the ribs. Because the F-715 ribs are clecoed to the F-705A bulkhead lower channel, it's not possible to push them out 1/32 inch past the floor plates. At the very aft end of the rib, the floor plate actually overhangs the web of the rib by about 1/32 inch. I'll file that down some, but even if I didn't, I think it would be fine since the edges of the floor plates are still inboard of the outboard most flanges of the F-705D bulkhead sides.

After that, I deburred two of the four new F-716 ribs (not including the lightening hole). These will be used to beef up the structure under the floor so I can mount additional seat belt brackets.