First I drilled a 1/8" hole close the end of the slot. The slot is actually 3/16". I don't believe in drilling to make any final radius. Some do, I don’t. I don’t have a center drill. I like to do the final radius with a round file.
I then used a hand hack saw to cut the slot slightly under size. Then a small flat file to expand it to just over 3/16”. Then finished it off the radius with the round file. I like my results.
As you can see in image 3, the longerons don’t extend all the way to the end of the bulkhead flange. But the longeron end notch fits perfectly flush with the bulkhead web. So, I’m good. Why was this slot an emotional task?
