Medusa
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I've got a beautiful Medusa, blowing F4 - I realize it's solenoids, or a short in a common solenoid wire.
Reading through the manual, seems to be lacking.
Does anyone have a visual map of the underside of the playfield with solenoid makes and numbers?
I'm trying to test each solenoid in/out of circuit and most of them have burned up labels - I know, bad sign.
Much appreciated in advance.
Quoted from Quench:Last page of the downloadable PDF manual has the coil types.
Disconnect J1 from the rectifier board - that will remove the playfield from the equation, just in case the short is around the front door coin lockout coil / cabinet knocker coil.
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Thanks again Quench ! I think I might have to make a map myself - I have been bottle fed too long with lots of pictures in my documentation
I have a problem with my Medusa - coils specifically.
Several burned up coils, and I'm tracking down what's in place and comparing to what came with it factory.
The target bank reset coils are NB 26-1900 (original NO 26-1900).
The closest I can come up with based on the coil chart should be 22 ohms. Have verified it's not my DMM.
What is the difference between an NO 26-1900 and NB 26-1900? Haven't been able to figure that out either, assuming it's lug position?
Quoted from Quench:Six years ago I posted some pics of the zipper flipper crank/pawl wear on my game:
https://pinside.com/pinball/forum/topic/medusa-owners-club/page/10#post-3913477
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Last year probably only 200-300 plays after those pictures were taken, a friend was playing and we heard a bang in the cabinet to find one of the plungers on the bottom of the cabinet and it's flipper crank hole blown out:[quoted image]
There was no way I was going to install new parts that were just going to do the same thing with metal on metal wear so I made up a more traditional setup - before and after pics:
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Excuse the rusty cranks, I'm waiting on new ones to come in.
I made new links from some POM plastic, new metal idle end stoppers and new EOS switch brackets to move the switches closer to crank and higher from the base plate. The new plunger/links probably turned out to be similar spec to Stern gen 2 flippers. The crank/pawls are early solid state Bally.
Did you make the metal idle end stoppers and EOS switch brackets? Or was there a part # you used? Looks like the coil 'shaft' is shorter. Was that from an existing rebuild kit? Looks like DE flipper rebuild kit parts almost.
Where do you find the POM plastic? Maybe even bakelite would work?
TIA.
Quoted from Quench:Yes I fabricated those metal brackets.
I bought a 300x300x3mm black sheet from AliExpress years ago:
https://www.aliexpress.com/item/32852877596.html
There's probably other sellers that are cheaper now.
I believe the grey plastic links used in DMD games is made of POM. Home roller door wheels are made of this material because of its high strength and low wear properties. I use it whenever making new flipper links now. Traditional Bakelite-fibre material could certainly be used otherwise.The coil plunger/shaft has to be shorter since the original design didn't have a link. My parts seller was selling packs of ten so I don't know what brand/game the plungers are from.
I did spend time measuring to try and make sure the flipper travel was about the same as original and the link angle on the crank was about the same at both extremes.
For the metal brackets: how did you fabricate them?
They look like 1/8" cold steel.
Did you have them CNC'd? Do you have a drawing or CAD file of them?
TIA!
Quoted from Quench:Nope, I crafted the metal parts the old fashioned way with a vice, hacksaw and hand-drill..
Has your game also suffered from severe wear on the cranks?
If I remember right the plunger and POM link are about the same size as those used on early Stern gen2 flipper assemblies. They can be used as a starting point. I looked at using Williams / Stern cranks but their arm length is short so stayed with using the previous gen Bally cranks.
The steel used was the same thickness as the original.
If you look at the third picture in my post above you'll notice the corner of the base plates are bent up a little so this needs to be taken into account when making the end stops so they sit flat.
If you're CNC'ing then you have the advantage of redoing parts if they don't turn out right.
Yeah my zipper flipper assy is pretty hacked up but looks largely complete. I can do some really basic 3d modeling.
I'm going to get into reassembling mine soon and will post info. Thx Quench!
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Anchorage, AK