Make a shopping list for your base frame: 1" x 12" lumber, measuring the length of your outer box, your vertical supports, and your shelving. Remember most wood comes in 96" sections, so you will have some waste. If you plan ahead how you're going to cut them, you can buy some shorter (72") or longer (120") sections to fit your design. Use poplar or maple over the low-end pine boards, since the knots make the wood hard to work with and paint.
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