We found plans for a simple bookcase and decided to build it right away. We liked the bookcase so much that we decided to build two more. We cut all the pieces in an assembly-line fashion and finished the second bookcase quickly. While assembling the third bookcase, we noticed there were two left sides instead of a right and a left. After thinking it through, we decided to build one more bookcase and cut two right sides to fix our mistake. We assembled these bookcases just like the others. When they were in position, we noticed that two of the bookcases were leaning slightly. We checked our measurements and looked over the plans. Then we discovered that the two new right sides were 3/8 in. shorter than the left sides. In our assembly-line haste, we’d goofed on the measurements. To conceal our mistake, we shimmed the shelves slightly to create the illusion of level.
