On Tue, 11 Feb 2020 02:28:44 +0000, Spalted Walt
wrote:

Ivan Vegvary wrote:

Tearing out sagging shelves in a 10ft. by 6ft. pantry. Would jike to put 18" deep shelves on the back wall. These would not be "cabinet" quality construction.
So, rip 18" wide plywood? Particle board? Bisquit join solid lumber?
Any thoughts appreciated.

The Sagulator:
https://www.woodbin.com/calcs/sagulator/

Highly recommended.