I decided to make good use of some of my mandatory "don't come to work" time. I'm continuing to tinker with the Playmatic Last Lap that I've now got booting and flipping. At this point, the only serious unresolved issue is that the displays aren't working (but are getting power), but that's a topic for another thread.

I'm currently working on the flippers. The two at the bottom use a coil that is no longer available-. The upper flipper coil has been swapped for a smaller Williams coil and it seems to be working fine, so I'm just going to change the sleeve and linkage and call it good. Do note, these flippers use a general purpose coil with only two lugs.

The lower flippers have two different coils (which is not correct). The one on the right flipper seems fine. The left flipper was awfully weak, even after rebuild. On a whim, I swapped in a Williams SA-23-850, with the diode removed. That took a bit of fitting, since the bobbin is a tiny bit longer than the Playmatic coil.

Anyway, the SA-23-850 works better than the one that was in there, but is still to weak to put the ball through the spinner and up to the top of the playfield. I'm looking for a substitute that's a little more powerful. I know about wire gauge and number of turns. How do I determine the correct bobbin size so I know it will fit? Or is there a coil you'd recommend?

Thanks in advance.

Both the “good” and “bad” playmatic coils are 2.9 ohms. The Williams coil I put in is 4 ohms.

There’s a large resistor and diode near the flippers on each side. Not sure what these are intended to do.

One would think, but it’s definitely not.

I didn’t, but that’s a good idea. The eos switch on the left looked like it had been sparking badly. One side was absolutely cratered, the other had a built up mound of metal. Filed the contacts smooth and polished them, and it was better.

I’ll swap them and report back.

You’re on to something... I swapped them, and the “bad” coil is fine. The other one is *better* on the left, but still not as strong as it should be. The resistor is one that I don’t have, so I’ll need to order it.

Thanks! I think I’ve got it solved... parts for the resistor setup are inbound. If I end up needing a new coil, I’ll reach out.