I made three sets of classroom mailboxes, for passing in papers / storing journals etc. Sides and back are 3/4" plywood, shelves are 1/4" plywood. Corners are rabbet and dado joints, my first time doing that. I did the cuts on my table saw. (I tried to route them, but didn’t get as clean a cut as I’d like with the cheap Ryobi bits I had.) Shelves slide into dados. The sides/centeres are designed so one fence location could cut the top and bottom dado. I didn’t have a dado stack, and am using a Shopsmith which has the table saw blade arbor on a quill, so I set the quill stop for my dado width and used that to make multiple cuts slightly apart. That worked fairly well but must have been slightly off on some cuts where it was very hard to slide the 1/4" plywood shelves in; I ended up sanding the edges of some slightly thinner.
Tried to post additional images in the post description but I got an infinite spinner when I tried to post, so adding them here instead.
One piece caught on the blade and kicked back, luckily (or by design actually) I was standing slightly to the side so it just dented the worktable behind me.
Lots of dados / rabbets to cut.
Assembly was fairly smooth, but some of the plywood was bowed so I ended up widening the dados on the sides/bottom for the back panel to sit into to make assembly a bit easier.
For three sets, it took 3x 4x8’ 3/4" plywood sheets and 3x 4x8’ 1/4" sheets, with a little room for scraps. I considered just a rabbet joint first but then decided on the rabbet and dado. I was relieved that everything went together as planned/measured!
Love seeing the extra clamping images and the sketches. Nice work!
