We need to replace some of our cheapo metal shelving that we are using in the pantry. Some of the shelves are bowing in towards the middle! I remember a thread where folks posted pictures of their pantries (of course, I can't find it now!) and someone posted pics of shelves made with 2 x 4's. If you have made your own shelves, what did you use for the uprights and what did you use for the shelves? Thanks!