Last weekend I took my son to the Maker Faire, and of course while we were there we had to get a souvenir. Kolya chose a “useless box kit“. If you don’t know what a useless box is, read along.
The video below will demonstrate the silliness better than words, but in short it’s a box with an “on” switch on the top. When you turn it on, an arm reaches out and turns itself off. The magic is a small DC motor and a double-throw switch. When you turn the switch on the motor rotates in one direction, moving the arm to flick the switch, reversing the motor. There is a limit switch in the reverse circuit that is triggered when the motor reaches the retracted position.
The instructions were clear, and assembly was straightforward. Kolya soldered most of the connections and assembled the box, I got to say (over and over) “did you read the instructions”?
Thanks to one of us carefully reading the instructions and testing the operation before we assembled it, the box worked on the first go.
It’s a fun little project, and now I want to make one for my office. But with a nice dovetailed wood box. I’ll let visitors discover it on their own.