How to Build an Adjustable-shelf Bookcase

Cut and trim the sides (A) to size. Clamp a scrap of perforated hardboard (pegboard) to the sides as a template to lay out and mark locations for shelf-pin holes as shown in the exploded view drawing.

With sides on a bench, drill 1/4-inch holes 3/8 inch deep at shelf-pin hole locations. Use an electric drill with a brad-point bit and a drill stop. Check the depth frequently; do not overdrill.

To safely rip plywood with a portable circular saw, use 2x4 supports laying on sawhorses and a kerf splitter to prevent kickback.

You can control the depth of the holes you drill without a drill stop by wrapping tape around the bit as a visible guide to the proper depth.