The encasing bench is your solution for dealing with too many items! It allows you to compress 9 of any item (as long as they are the same) into a single case! You can even compress cases into cases!
Place 9 of a same type of item in the grid, and wooden planks in the middle open slot, and a crate will show up on the right. Pull the crate and the items will disappear. They are now compressed! To decompress them put the crate in a crafting table. The encaser is not a crafting table! You can't craft with it! It can not be automated, for that you have to upgrade it to an Auto Encaser.