Some months ago I bought a Devil Riders, and to be honest I never even heard of Zaccaria before. (and I live in Europe, go figure) But I was very surprised by the quality of the playfield and actually the whole machine. They are very easy to strip and clean. The machine was in an overall nice condition, but the ramps and the other metal pieces bothered me. They had gotten dull and spotted over the time.
So I dicided to give 'em a little treatment. Using only this:
You can see the metal parts were once chromed, but now we were going for the brushed steel look.
Here the left ramp is untreated and the right ramp is treated:
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World of difference if you ask me. This is a very budget friendly way to give you all the metal parts, and older machines have a lot of them, a new life! I ended up doing all the metal parts on the playfield, and even a few underneath the playfield. Just make sure you keep brushing in one direction.