On Tuesday I bought 3/4" plywood so the actual shelves are okay. The frame is old 2x4 and pretty much worse for wear. ( half hockey stick, half airplane propeller). However, the unit is very sturdy and already getting loaded down with coloured glass and related gear. The rough guess for weight was the load bearing shelves would have to carry hundreds of pounds once filled so everything is heavily engineered. Interestingly once the unit was put into the corner and loaded down it works perfectly.
If you look closely at the construction you will see that all but the top shelf directly supported with wood, not just screwed into place. Now that the kiln has found it home I will make a support to go underneath the bottom shelf in the middle so there are supporting legs every two feet.
There are little touches that I included that I put on any kind of unit like this. The back of the shelves have a two inch piece of trim so that things can't fall off the back of the shelf if pushed too far. Each shelf has an enclosed ends so that is can be used to the very edge without things falling off. You really don't want bits of glass falling behind the shelves or off the end onto the concrete floor. The upright dividers are held in place by pocket holes rather than just screwing though the shelf into the end grain of the plywood.(construction grade).
The goal was to make a solid, serviceable storage unit and anticipate the needs and uses so that it will not have to be replaced or repaired any time soon. The rugged appearance and low cost are just bonuses.
Two follow up notes:
1. I didn't miss the table saw at all in this project. I used my sliding mitre saw, jig saw, band saw and circular saw. Maybe it was a little slower to finish this, but not much.
This is the painting that is on the right hand wall. My Mother's Mother painted it in the 1970's. It is a landscape with a small camp (cottage) in the forest near Espanola Ontario. I live in the city now but still love the north.