On Apr 18, 9:27*am, "Jeff D." wrote:
I'm building a wall of storage shelving for my 45 record collection (appx.
20,000). The records are stored 200/box and each box is 16x8x9, weighing
15lbs. Will 3/4" plywood shelving 4 feet long support this load without
deflecting, each shelve will be loaded to 75lbs with supports on the ends
only.

It might be cheaper and less work to get steel pre made shelves