Fabricating your own pinball plastics and lane guides

As work continues on the restoration of the Bally Mr. & Mrs. Pac Man machine, I have run into a problem.  I got the machine working, but after playing a few games I noticed the ball getting stuck next to the lower left flipper.  The problem is, this game used a piece of plastic as part of the rail guide that had one end chipped off, forming a crevice the ball would constantly get stuck on.  This is not a printed plastic and this game doesn’t have a whole lot of available spare parts for purchase at various places, so my main option is to fabricate my own lane guide…

After a quick trip to the hardware store to pick up the parts, I show off one of the cool tools in my workshop…

After cutting out the plexi piece, let’s see how it looks…

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Fixing a dead dot matrix display board

The other day the DMD just went “poof” on one of my machines.  After doing a little research, and checking connections and things, I realized the DMD board died.  In this installment, I walk through the process of rebuilding the power supply-portion of a Bally/Williams WPC DMD board.  In part 1 I describe what I’m doing and introduce you to the tools I’m using.

 

Next up, let’s talk about using a meter to check circuit board traces as we go along..

Desoldering and replacing components.

Now the moment of truth!  One thing I want to add is pay very close attention to each item you are replacing on these boards.  Two diodes, capacitors or transistors may look alike, but have slightly different values or part #s.  The three power transistors and the diodes are not all the same.  You may have to bust out a magnifying glass to note the different in the markings on each part.  This should also be cross-referenced with the schematics and/or parts list from the game manual.