sorry to bump this, but there is a lot of great info. I'm trying to build a 8-10 ft box for a backyard and was wondering on the thickness. read people used everything from 1/4" to 1/2" and was wondering if there was any feed back? HDPE is where I'm going as funds are limited, but if 1/4" works, I might be able to spring for UHMW.
¼ sounds very thin to countersink the screws, or are people just gorilla gluing this to a sheet of plywood?