I started the day by going to home depot to by materials to build a drilling rig for the drill press. Whenever I have holes I need to drill with odd parts or bits (like the 1-1/2" holes in the 716 ribs) I like to build a jig to properly secure everything. This gives a stable platform and the ability to clamp everything.
I then drew 1 1/2" reference circles on the parts as I will be initially drilling the holes to 1 3/8" and then opening them up to 1 1/2" (Better room for error this way).
I was then ready to drill four F-716 ribs.
Now I needed to cut the enlarged access hole. I drew reference lines first.
Then I made my initial cuts with aviation snips and then went to work with a file. Slowly but surely the material was taken away, and I worked up to the lines. Then I cleaned all edges with the small 3M wheel on the die grinder.
