I've been busy making 1 foot square boxes to mount some of my prints. The weird thing is I am using pizza boxes. I've been experimenting with the idea for awhile now, and I think I'm getting it "down pat".
I ordered a stack of 50 new boxes from a restaurant supply company. (I think the shipping actually cost more than the boxes.) They came just wrapped in plastic.
So, they're very easy to assemble... but then I put quite a bit of work into them. I've figured out that packing them with styrofoam is probably the best way to go. I'd really like to get a 4x8 sheet of styrofoam insulation from Home Depot, but for now I've been using some salvaged packing material.
I cut off a few tabs and sand a few small areas. Then I tape them up using both masking tape and brown kraft tape, the kind used for watercolor painting. Once that is thoroughly dry, I begin painting them with gesso. I'm actually using a flat white latex primer, but gesso sounds more official. It's important not to get them too wet or put the paint on too heavily at this stage because the cardboard will get all soggy and they can buckle or sag.
I've also bought some nice foamcore mounting boards which I'm planning to actually mount the artwork onto. This will provide a nice flat surface and add to the strength of the face of the board.
They really are looking nice. I think the trickiest part will be mounting the art work onto the boards. Getting them on straight can be nerve racking. I'm using acid-free spray mount - you really only get one chance to get it right.
I have a few more to go to make an even dozen. They will be sturdy, but lightweight for shipping. I'm thinking I can pack a box of them and ship a whole show's-worth to a gallery somewhere.