Eric, I think we are both are off in our calculations. The total of 256' of 2x2 is pretty darn close. Multiply the 256 by 2.25 (as 2x2 are really only 1 1/2" x 1 1/2". So multiply 1.5x1.5 and you get 2.25 cubic inches per line feet) and there you have it. A total of 576 cubic inches for the 2x2 bracing. Then add a bit more for the 1x2 (what maybe onther 40 cubic inches). Figure a little over 600 cubic inches for the whole thing. I hope my way of calculating is correct. This way of building the boxes makes it eaiser on one hand and maybe a bit more trouble on another. I will say this... that box in not coming apart!