Fan-Tas-Tic Pinball, Part 3

Some impressions from the cleaning process

State of the playing field Before / After

I used white spirit and spot eraser pads for cleaning and automotive wax for sealing it.

The insides Before / After

The playfield has been stripped and all cables removed. I kept the leaf-switches but will read them in a matrix configuration.

It was possible to take out the relay based control board in one piece. The new ARM based control board is already in place.

In its original configuration, the pinball contains only one single transistor which is part of a delay circuit. All the other functions were done electromechanically.

  

Fan-Tas-Tic Pinball, Part 2

The Fan-Tas-Tic controller

The new homebrew controller board for the pinball machine. It's general job is to read a lot of switches and drive a lot of solenoids. 

The game logic runs on a Raspberry pi, which communicates over a USB-serial connection with the controller board.

Circuit board

Firmware

Mainboard, as rendered by KiCad

Mainboard, getting CNCed

Mainboard, tested and working

Unfortunately there was a glitch during toolpath generation of the second layer, which we only noticed very late in the milling process. While the board was functional, the high current traces for the solenoids turned out much more narrow than intended. They instantly burned up during the first test with a real solenoid (24 V, 3 Ohm, 8 Amps peak.). As a workaround I soldered thick copper wire on-top of these traces.

High current traces fixed

Driving WS2812 LED strings. Check of timing.

Fan-Tas-Tic Pinball, Part 1

Refurbishing and upgrading a electromechanical pinball machine from the seventies.

      

Right: How it looks like now. Left: How it might end up

Taking the monster apart

Under the hood. This thing is full of relays and mechanical switches -- a lost art.

Underneath the playfield, showing the solenoids for the flippers.

At this point, the machine is in quite a bad state. All the rubbers have turned into brittle plastic, many lamps are blown, the playfield is a filthy mess and the playfield window is cracked.

We took a last video of the machine with its original electromechanical brain, before we have teared it completely apart:

Turns out it almost works. The score counting wheels have some issues. Sometimes they get stuck, sometimes the reset process never finishes.