This electro mechanical arrangement obviates the need for any computer control of this device. The above sequence prevents the coil from overheating and possibly burning out if the flipper button is held closed. This reduces the current through the two coils but holds the mechanism in position until the flipper button is released. Towards the end of its travel a switch is opened which removes the short from the secondary coil. When the flipper button is operated, the primary coil is energised from the 30volt supply and the plunger enters the coil and forcefully rotates the mechanism. The secondary coil of a higher resistance is initially shorted out. The primary winding, being of low resistance and drawing about 2 amps, provides the power for the “bat” to strike the ball hard and send it up the play-field at speed. The solenoid coil contains two windings connected in series. It's available to download now from The animation illustrates how the flipper mechanism operates. Update May 2020: I've recently published a new ebook called Animated Arduino, an interactive ebook which aims to provide a better understanding of some of the concepts that you will encounter whilst you learn to program the Arduino, giving you the confidence to progress in writing more ambitious code for your projects. I hope that, with the information that I am sharing here that you will be inspired to design and build a pinball based on your favourite theme. I describe the pinball mechanisms and how to arrange and mount them on a pinball play field. That machine forms the basis of this instructable. The first machine that I built, featuring Alice in Wonderland, is electromechanical and thus not so complex. A comprehensive e-book showing how to make a solid state machine is available as a download from the website.

The last two machines were solid state controlled by Arduinos and having sound, lighting sequences and scoring. I'm a retired engineer and practising artist and I've have built three pinball machines in the last five years and have video clips, showing them being played, on my website.

Build your own slot machine