I just added an article to the website (Making A Cardboard Box To Ship Art) that has plans and instructions for making a cardboard box. To make any size box, all you have to do is plug your dimensions into the expressions for each measurement on the plans. You can even download and print the plans (but not the instructions – hmmm).
As per my last post, you can also reach this article from “Tips & Techniques” on the main menu. Click on “Printing & Beyond”, which will take you to the “Do-It-Yourself Ideas For Finishing Your Photographs“. The sitemap will also work.
P.S. I’ve promised to publish plans and instructions for making our booth display panels in a form that people can actually use, instead of just the notes and scribbles I made for myself at the time, but those won’t be ready for the beginning of the next Florida art festival season as I had hoped. The cost of materials for one three-foot wide panel was about $50 a few years back. Stay tuned.