Well done Hombre 3am posting this thats dedication
It all looks ok and obviously works for you just a couple of observations
(A). Its best not to have any flat surface on the bottom rail and the bevel to extend the full length so to shed water
(B). And you may fined that if you extend the part marked as Y so as to reach the bottom of the rebate on the top and bottom rail and then having reduced the top and bottom rail in thickness to accommodate Y then glue the top and bottom rail to Y will result in a stronger joint.
Thank you Tom for your constructive comments.
(A) Accepted, but the flat is there to accommodate 9mm (standard), 12mm or 18mm ply as might be chosen, even though I personally use 9mm. I can change that without modification to my top and bottom rails.
(B). A conscious decision was made to make the end plate assembly with an inset end plate, rather than outset as you describe. It allows me to change my end plate from 9mm without change to the top/bottom rails. My feeling is that the strength imparted by the end plate to the completed box is one of rigidity, much like the thin panels in a door frame (shhhh not a word about the jointing difference). It keeps the box square just by it's presence, more so in a 14x12 box. The inset end plate also saves plywood, making the construction of supers almost an offcut exercise.
I thought long and hard about how I wanted to do things and feel that I reached a happy workable compromise. I would like to think that you appreciate my decisions, even if not actually go as far as condoning them.
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