After discovering the front upper bunk needed a support across the 5'-10" span. I decided to use some 3/4" angle iron. After getting that installed, I discovered the angle iron tied to the outer walls and the bunk shelf (1/2" plywood) was not going to support weight without dangerously sagging. I decided to add a piece of 3/4"x 1.5" walnut that I have been knocking over in the shop for the past 6 months. I decided to use the same Button head Cap Screws as the window trim rings. but, when I drilled through the Walnut and 1/8" thick angle iron. I discovered that the Walnut board was 7/8" thick. and that the 1" long Button head Screws were to short.
I picked up some more Button Head Screws at the hardware store yesterday in 1 1/4" length and some square nuts to use to bolt toe Walnut facing board onto the angle Iron.
after pulling the Walnut up even with the 1/2" ply, and having the Chamfer milled into the edge of the board. The screw holes ended up to close to the horizontal leg of the angle. I figured the square nuts would be ideal to thread onto the screws. well, after getting home, I discovered I needed to mill 1/8" off one of the flats of the square nut to make it possible to fit the horizontal leg of the angle and thread onto the screw. It was about 9pm last night when I finally finished fitting the assembly up. here is a cruddy pic. some better ones to follow this weekend.

Making big pieces of wood into the wrong size..... for over 30 years....