YouTube channel How To Mechatronics has created a great tutorial with full instructions on how to create your very own Arduino powered 3D wire bending machine.

To solve the problem without sourcing a new switch, [Jean-Noel] built his own Arduino based Dahlander switch. This consists of three relays that select the wiring configuration for each speed mode.

If you want to attach a light, motor or sensor to the Arduino board, you just snap it on -- you can spend more of your time coding rather than dealing with wiring and other hardware hassles.