This thread will document my second playfield swap, Medusa. My recent Fathom playfield swap went well, so I’m going to take advantage of having lessons learned fresh in my mind.

Compared to Fathom, which was in good shape, this game is kind of a hot mess. Tons of hacks and the flippers are garbage.

I have a Silver CPR playfield, new plastics, apron, drop targets, flipper rebuild kits, #44 lamp sockets, posts, etc.

I also scored a NOS kickout part that’s hard to come by used by Shield of the Gods. Someone installed a slingshot mech which actually worked fairly well, but I’ll trying to keep this section original.

Like before, I labeled everything under the playfield. This game has less mechs than Fathom but a pretty complex flipper system. I’m nervous about rebuilding the entire mech and all flippers, but too late now.

After the wire harness is off, everything goes in the wash and I pre-drill the CPR playfield.

Playfield:
C53BAC6D-1DB7-4B76-A3A6-2B6560A6451F (resized).jpeg

Labels:
820EFB7A-DD9C-4B4B-8BDE-3891CCB0E4B0 (resized).jpeg

Disconnected mechs so far:
310CA5D8-291B-4E7D-93C5-55380024B8DC (resized).jpeg

CPR playfield:
8697A43A-89FB-4928-8F00-1D026DE7FCC3 (resized).jpeg

New parts:
AE5B861E-FAAE-4A4C-8663-59821EA4A110 (resized).jpeg

NOS part:
image (resized).jpg

I expect this one should take me a month or so barring any disasters.

That would be very helpful, thanks. I’m using pbresource Bally rebuild kits, not original, but hopefully more reliable. I’m sure I’ll be reaching out!

Harness is free. Next is removing the rest of the mechs and cleaning.

DAECB18F-501C-47E2-96AC-51C13557D285 (resized).jpeg

F1C6912D-7B21-403A-ACE5-BC4A8DC206D4 (resized).jpeg

It’s 3M painters tape. It survived the wash last time with all labels intact, no problem.

Slow going. T-nuts installed and about 30% of the lamp sockets.

Wire harness and mechs go in the wash hopefully tomorrow.

Because the #44 lamp sockets take up more real estate, I had to move some of the pilot holes to accommodate.
1926E87D-B94E-4B4F-A63E-2CB310775C72 (resized).jpeg31FB1B2A-06BB-4144-BFD4-C238B2ED95BF (resized).jpeg

image (resized).jpg

Mechs and wire harness washed. Most of the sockets are installed.

Next up, clean and rebuild the drop targets. Rebuilding the flippers will take some time.

2223AF72-9255-4090-AE6F-8DA347A41203 (resized).jpeg

image (resized).jpg

image (resized).jpg

Good point on the light bar. It was pretty tight pulling off, so that’s a problem I’ll face when I get closer.

Reese rails should be here in the next few weeks.

I’m short three lamp sockets which prevents me from finishing the bare wire. Yet another order with Steve...

In the meanwhile, I’m still cleaning mechs but attached a few to the playfield. Once I get the missing sockets, I’ll finish the wire and start soldering.

59159307-3BCE-40E1-9081-551489F50DD5 (resized).jpeg

Replaced gross drop targets and standup targets with minty new ones

Old:
BAC6E5E2-9154-4A6A-B578-02019BDCF561 (resized).jpeg
Shiny:
F1B65D85-88CD-44FA-B877-8D5E43101E92 (resized).jpeg

No additional clearcoating. The clear from CPR is just fine, though some may want to take the extra time and expense to send it off. It was a Silver from 2016, so I think it's had enough time to cure.

Removing the harness isn't bad as long as you take lots of pictures, label everything, keep 1/4" wire to each socket and keep the donor playfield handy. Straight to the wash to get rid of 40 years of gunk and you're good to go.

I picked up #44 lamp sockets from Steve at pbresource. I can order on Monday morning and they're at my house on Tuesday.

http://www.pbresource.com/sockets.html

You'll need A2913, A2914, A2916 and A1363. I ordered 5 more than I thought I'd need and I still ran out. The game uses a ton of A2916. You'll need maybe 30' of bare wire.

Everything has been straightforward so far, but I'm still apprehensive about the four flipper rebuilds combined with the zipper flipper mech. The game was hacked to death, and I'm downgrading the lower flipper to 70's mechs. The upper mech coils were missing the sleeve, so I bought new coils (same as lower flippers). I try to only fix one thing at a time to help troubleshooting, but in addition to re-populating the game, there will be a lot of new parts. We'll see what happens when I plug it in...

One flipper rebuilt, three to go.

Old:
74C9F362-BEDB-4B1E-B7EC-E92C97475437 (resized).jpeg
New:
0FEA0B80-89F2-4DCA-8844-179D0262C9F0 (resized).jpeg

Pinrestore sells them (solder lugs). I 100% stole this idea from HEP.

Bottom two flippers rebuilt and attached. Lamp sockets arrived today, so I’ll finish the bare wire.

image (resized).jpg

Ground braid done and soldered. All lamps done. Pop bumpers and the dreaded zipper flipper mech are next.

image (resized).jpg

image (resized).jpg

The 2916 sockets have two lugs. One of them isn’t necessary. The bare wire attaches to C (with the solder lug) and the control wire attaches to A.
1530AC2F-47C8-476E-8781-ED9328F6750C (resized).jpeg

There are a few sockets without the bare wire connected by a bridge due to mechs in the way. It’s a crowded playfield.
image (resized).jpgimage (resized).jpg

Zipper flipper mech disassembled. Will clean and install flipper rebuild kit with new coils.

image (resized).jpgimage (resized).jpg

Question for the smart kids... can I add a few drops of lubricant to the metal on metal portions?image (resized).jpg

Back together and cleaned. I’ll finish the plungers and switches tomorrow. Everything seems to work properly, no extra parts.

One of the screws was stripped, so that cost me 20 minutes of cursing and dremeling.
image (resized).jpg

The mech was getting caught on the slingshot screw. By the look of the existing wear on the metal, this seems to be preexisting. I removed the screw, and everything works.
image (resized).jpg

image (resized).jpg

Fumbled my way through the punch tool to assemble the upper flippers. Everything seems to function well.

There is a lot of play in the zipper flipper mech, so I’m not sure if that’s by design or I just replicated hacks that were already on the game.

Pop bumpers are next, then the wire harness.

01882C64-FD16-4588-9A30-04C243480D6C (resized).jpeg

C5290F9A-878D-47B0-88B1-38FB4DC0B4DD (resized).jpeg

The whole mech is not super tight like a normal flipper. The zipper flippers have about 1/4” of play up and down on the playfield. Not sure if this is by design or I’m missing some washers.

Pulling up:
image (resized).jpg

Pushing down:
image (resized).jpg

Ready for the wire harness:
D7F34426-532D-4B39-8FB7-37F3509ACADF (resized).jpeg

And boom:
CE3B9C3A-A585-46E8-9A2F-9C69682C27AF (resized).jpeg

Thanks, and I’ve already noticed a subtle slant (and drag) with the flippers that could be fixed with an extra washer. I’ll finish the wire harness and make sure the top flippers don’t drag when it’s right side up.

Slow going. I have about 40% of the underside done. Another order with Steve at pbresource today because I keep discovering broken stuff.

Progress:
800F3F2B-F016-4513-A9D9-CC822DE1883A (resized).jpeg
WTF:
image (resized).jpg

It’s starting to get very crowded. I’m about 75% done with the underside. I had to rebuild the slingshots and the pop bumpers will be a challenge.

36FF07CA-D1B0-40EE-8C77-347656424C10 (resized).jpeg

FB2EFCB1-A696-44CD-B86E-C0EF228941CE (resized).jpeg

image (resized).jpg

Yeah, I’ll get to that part within the next few days and will post pictures.

I finished the corner with rollovers and that just sucked. No room and tons of wires.

I tested the GI and found a bad socket and some wire bridges I forgot, but everything worked for the most part.

The awful corner:
0A17FDDC-EECC-481E-90DC-896A549D23FC (resized).jpeg

Testing GI:
E0EC2D97-F0AF-4EC5-8ACE-6C93BBE7BBBC (resized).jpeg

Ha, someone’s idea of fun...

All GI wired. The top left GI doesn’t come on with the rest, but when I tie power to that area, the four lights work. Are they tied to a separate connection? I am not a master of reading schematics.
image (resized).jpgimage (resized).jpg

Thanks, and I was actually going to order flex tips for that reason. I used clear dome LEDs for Fathom and the light was super dim. Yet another order with Comet...

Everything is done bottom side minus the pop bumpers. I saved the best for last since the pops have close to 50 solder points.

Rebuilding the switches and flippers was a pain. The bridge wire between the coil and switch was toast, so I used some spare 18 gauge wire. Hopefully that works.
B2BCC6EA-ACB8-435A-A17E-9683385454BE (resized).jpeg

Bottom done. I hate pop bumpers. Some jackwagon dropped super glue down one of the pops and crudded up the entire mech.

Rails are on the way, next up is the topside.

855A09E4-41C4-4171-9E14-9B66013F61C2 (resized).jpeg

Once the pops were connected to the GI, the circuit was complete and all of it works.

image (resized).jpg

I previously swapped a Fathom playfield and molexed every coil. With Medusa, I probably did 50%.

With the zipper flippers, I added new coils and elected just to solder to the lugs. I may re-visit molexing the rest of the coils when I restore the cabinet.

Metal tumbled on the lower half of the playfield. Lots of micro problems with things not fitting exactly.

1. CPR lane guide holes didn’t match up. Plus, the thickness of the plastic protectors prevented the screw from biting. And the LED was too tall. I did some light dremeling and lined everything up.

2. One of the posts was held with a wood screw on the donor game and a t-nut machine screw on the CPR playfield. Rather than buy one screw plus shipping and waiting, I used a bamboo shish kebob stick and super glue. I’ll trim and drill once it’s dry.

Lower playfield:
E0031ABA-B4BE-4E18-90FD-467C36594EE0 (resized).jpeg

Lane guides:
DC53E72D-A54F-45C7-92C7-B4C45C19E03B (resized).jpeg

Fixing a wide drill hole:
64D5231F-2B76-4259-9B97-9D7A7FAC8DAA (resized).jpeg

New XPin displays arrived today

BA5CF5DD-A41F-4D43-8D94-E0CB59145D73 (resized).jpeg

image (resized).jpg

In this case, the hole was pre-drilled. I added the t-nut to the bottom, but the donor game had a wood screw here. Super weird.

Ha, no. CPR is great if you have certain expectations. Plug and play is not one of them.

True. The time to solder and crimp is about equal, though. No extra effort vs. a slight reward if something happens down the line. No harm either way.

Ha, I’ve had that internal debate so many times. “Should I half-ass this particular part...?”

The answer is usually no... unless no one will ever see it.

This game has a lot of red posts

35369D4C-9429-40D5-B17C-54CFC1DD2058 (resized).jpeg

A3AFB7C7-012D-4F2B-B8C9-7EB40413914E (resized).jpeg

F3BE3ED7-82C7-4A3F-BC16-294ABEDB1A09 (resized).jpeg

About 75% finished with the topside. The rails were supposed to be here two days ago, but like last time, there’s some kind of Post Office time/space vortex between here and Virginia.

The rubbers may be off, so if anyone has a Medusa, I’d appreciate a sanity check. The rubber guide didn’t match the donor game which didn’t match other games I’ve seen. I eyeballed some of the rubber placement.

In the meanwhile, I can gap switches and start the apron portion.

image (resized).jpg

image (resized).jpg

image (resized).jpg

Again, totally not your fault! The USPS is comical at this point, though. Last time the package was ‘delayed, but still enroute.’ Same thing now.

It’s all good, as there’s tons of stuff to do in the meanwhile.

Medusa does not have an adjustable drop target plate. Because the CPR playfield is thicker, the drop targets sit lower when dropped, risking a stuck ball.

I stole this from another thread, but magnetic tape works great on the bottom portion of the drop mech. A single strip will provide the required height to ensure the drops are level with the playfield.

1FD486B2-7F34-4029-8E24-A00FA62E46AE (resized).jpeg

1ACCE986-B4FE-4ACB-8174-4DA7DE0F3C4C (resized).jpeg

CC29080F-B74E-4B3D-8662-B9F09D996BE9 (resized).jpeg

Old and gross:
7B192980-7D58-4F2C-9FE0-AF39093CAA8E (resized).jpeg

New and shiny:
8C2EE075-F92D-49F3-AA2B-013090DE0711 (resized).jpeg

Good to know!

Spinner and back posts installed. While I wait for the rails, I can sand the star inserts and gap switches.

image (resized).jpg

Rails arrived today. Thanks Taylor! Like last time, they’re great.

Lots of drilling and fitting. The playfield was bowed in the middle due to the weight, so I used clamps to keep the rails level with the playfield while I drilled. We’re getting close!
F928D60A-515D-4FF6-B6BB-1E4FCDB3E279 (resized).jpeg38C85FDC-3387-41C9-87BB-579E9C9EDBBA (resized).jpegE9E346D4-B714-4B63-ABF5-7B58B72FC8C3 (resized).jpeg2EC204F3-BD35-4B7C-A3A7-FBAAF7A23244 (resized).jpeg

https://pinside.com/pinball/forum/topic/gauging-interest-in-all-metal-pf-rotisseries-for-18000-shipped

Purchased here. I bought the Pro version and took it to my local powdercoat guy. It’s been great so far.

All plastics installed. Finishing nails and 2-way gates added.

Star rollovers next, then switch gaps. Once those are done, I’ll wrestle with the light bar and 7-drop mech.

I expect to drop it in the cab in the next couple of days.

5BF74E56-F3AD-4BCB-9B7F-2BF43BB2FC6B (resized).jpeg

Switches gapped. Sanding the star inserts tomorrow and will hopefully fit the light bar. I think that part will be a bitch.

In the meanwhile, the game looks pretty neat lit up.

D1FD63C7-C1EF-4CC4-A351-4232164D0199 (resized).jpeg

Light bar installed. There’s about a 10 degree cant due to the CPR playfield thickness. It’s subtle, but it’s there. I’ll see how it looks in the game before I make any permanent modifications.

E67E7977-E78C-443E-84EC-BD87C74299EC (resized).jpeg

DE59EBF0-F36B-41A2-94AB-65C24784BD12 (resized).jpeg

9BB6C493-65D2-4852-9B74-6A02FEB8E0BF (resized).jpeg

Light bar photos as requested:

D6D4FAC6-7546-4F18-93E2-EFEAC941EBE8 (resized).jpeg

78277FA0-E902-462D-965D-7833DD1B54D7 (resized).jpeg

E7C135E6-0978-4A65-856B-6D713E4CEF7B (resized).jpeg

AB05F20C-BB59-4AB1-98DB-DB5693F16771 (resized).jpeg

53DA5DAE-6852-4B12-9FF8-21324B0FBE50 (resized).jpeg

Ready to drop in the cab. That’s a lot of wires.

image (resized).jpg

She lived!... for a brief amount of time.

The game flipped, all inserts were working. Drop targets worked fine. No scoring. The pop bumpers and slingshots didn’t work. Sound was fine.

Then the game died. Nothing.

I’m going through the usual culprits, but I did change the power cord today. I also tripped the wall circuit, but even after resetting, no dice.

Any ideas before I start digging?

Inserts working, game flipping:
E1F3DA98-B1C5-4651-9B9A-D7C771EA31A0 (resized).jpeg

Power cord before:
E8D60C66-5019-4AD6-9FA6-4317374316B6 (resized).jpeg

Power cord after:
24A612FA-06F3-45D4-9D5D-9629C6D99388 (resized).jpeg

Backbox:
image (resized).jpg

Power Module. J5 was burned and hacked before the swap.

image (resized).jpg

Yeah, I disconnected everything from the boards. No luck.

The filter reads 122V, so normal voltage coming in. However, my breaker keeps resetting. It’s just totally dead. Hmmmm.

But the playfield looks really nice.

The GFCI for the wall outlet, yeah.

This is bananas. I was ready to troubleshoot the score and coils when the whole game died. I mean I can’t get anything. Troubleshooting voltages and electricity is my kryptonite, so this is going to be fun.

Same thing. No dice.

I’ll start a tech thread after doing more troubleshooting. Bummer, because when the game fired up, I was super excited. That’s pinball for ya...

^^
Thanks for the tips! My soldering skills are terrible, so it’s 100% possible I used too much and shorted something out.

New 130V MOV on the way. I plan to de-solder, clean and test the filter, and try again.

If I need a new line filter, would a generic 115V suffice?

B6D9F07E-CD65-4580-AC0F-E604AE6B2C51 (resized).jpeg

I re-soldered the line filter. Good voltage, still no power. I’m assuming I fried the filter, so I’ll order a new one and try again with the new MOV.

95K was the max reading, holding steady ~50K.

Thanks again for the help everyone.
A346CCB2-100F-46C1-9D37-354382F070BA (resized).jpeg

120V after the filter into the tech port. Can I assume this means the filter is supplying power? Next would be checking to see if the power switch failed.

Yeah, good call. My intent was to rebuild the cab and all hacked connections after the swap. I only elected to change the cord because the old ground plug was snipped and providing a low voltage shock through the metal.

94235104-8D68-432E-B7F2-7987FFF630CF (resized).jpeg

Back in business!

She’s alive, for real this time. Indeed, I likely shorted the filter with my shitty solder job. I blew the 3A fuse.

The pops and score weren’t working originally because I had a bad connection to the MPU. The wires had too much tension and pulled the connection.

Now, everything appears to work normally. I’ll still replace the filter and MOV. “It’s probably just a fuse...”

Thanks for the help everyone!

5AA9F962-1DAE-4532-A759-CA318EBD1161 (resized).jpeg

image (resized).jpg

Thank you. Yeah, there so many hacks in this game I don’t know where to begin. The 3A blew again after about 10 minutes of play.
image (resized).jpg

Likely fast blow. I have a 3A slow blow if that’s what Bally uses.

image (resized).jpg

I swapped the fuse with a SB. Thank you sir.

Also, again, a huge thanks for everyone’s help working out the gremlins. Especially Skidave for letting me know one of my flippers had a diode installed backwards, likely causing many of my issues.

This is what happens when a coil has a backwards diode. I can’t even pull out the sleeve.

67FBDF91-1276-4D4E-A88E-CDD5EC45EA2A (resized).jpeg

I’m not even going to bother, I have a replacement on the way. Yet another lesson for my bag of tricks...

Received the replacement coil (with the diodes installed correctly) and soldered/installed.

No issues, game plays perfectly. No resets, no blown fuses after 30 minutes or so of gameplay. I have a few stuck switches and a few rollovers are giving me shit, but that’s the easy stuff. It’s absolutely playable.

I have a replacement filter and MOV for the next fix. I’ll get everything working 100%, then on to the cabinet.

I’ll wrap up this thread with a big thanks for everyone who chimed in to help or offer some encouragement!

8D34A3B5-CF83-45B6-921D-C09D58D4F255 (resized).jpeg

image (resized).jpg

I’ve been thinking about that. We’re in the middle of a move, but once we’re settled, I’m going to do the cabinet. When the playfield is out, I’ll likely remove the light bar and gently route the underside where the brackets attach.

My first thought was ‘do no harm’ to the playfield, but routing may be the best option.

Revisiting this thread. I took a long break after swapping playfields for Medusa and Fathom before doing the cabinet.

Medusa is fully stripped and primed. I used fiberglass resin to level any cracks and repair the bottom and back. All parts are taking an Evaporust bath or in the tumbler. New trim, legs and boards are waiting. Once the base color fully dries, Pinball Pimp stencils are next.
839C75F3-B77F-49D1-B4F8-C4078A6FD5C5 (resized).jpegDCA0369C-8881-4F1F-9790-D2E704CFE051 (resized).jpeg

Thanks, glad the pictures helped.

The cabinet is finished, and the stencils… did not go well. The head is finished, but the gold paint didn’t adhere to the cabinet at all. The gold stuck to the stencils, so I’m back to sanding and I’ll start over. Very frustrating, but I’ll go in sections next time vs spraying the entire side.

Almost ready.

The cabinet and head are primed and sprayed. The head stencils went okay, but the cabinet stencils went really bad. I had to re-do them because much of the paint pulled with the stencil.

For the second time, I cut the stencils into 11 parts instead of three sections. It took hours, but I wasn’t taking any chances. Only a few spots I need to fix.

The cabinet and head are repopulated, slowly checking stuff while I wait to drop the playfield.

I elected to not replace the floor of the game… I didn’t want to screw it up. Instead, I sanded and painted. The back was totally waterlogged, but the fiberglass resin worked great.
3C6FB8F0-9331-4C45-A314-BC008DFA5B79 (resized).jpeg8D25FBE8-2181-4033-9CF9-4093A46E8222 (resized).jpegF0F58AA2-04A6-413F-A32F-E1637C48F272 (resized).jpegAC50884F-C621-477F-8085-87292C6A154F (resized).jpeg7D6176AC-7537-4946-8DE6-16357322503A (resized).jpeg

Thanks bud! Fired her up and she’s working great. I have a few stuck switches giving me crazy points, but I can track those down.

image (resized).jpg

image (resized).jpg

image (resized).jpg

image (resized).jpg

Before:
07AADB44-BCC8-4BF3-A307-9AF376C91645 (resized).jpeg61F9A175-F12A-4B8E-B17E-CCB7CDD7A272 (resized).jpeg7E54A0AD-6B46-48C7-8CB6-BF2738DFE642 (resized).jpeg9AD21323-B788-4378-9F3A-6C78A6E44B71 (resized).jpegA6A68D56-C5DC-429E-BD8E-AAF44C557905 (resized).jpeg

After:
DE9FCE7B-21C4-4782-8F16-F4A8853C2B5F (resized).jpeg
image (resized).jpgimage (resized).jpgimage (resized).jpg

I used three different golds.

The Rustoleum metallic bright finish was okay. I used that for the head. Very sharp edges, though.

The Krylon Fusion can rot in hell. Dried right away and cost me another week and a set of stencils.

The Rustoleum universal was awesome. That’s on the cabinet. Best of the bunch and the cheapest.
image (resized).jpg

That looks great! I debated sanding and clearing, but to be honest, we just moved to smaller house and I had taken over half the new house with Medusa workbench shit. I (and the family) was ready to be done.

Thanks!

The lamp socket is A2916 on pbresource.

I purchased the lugs to solder the ground braid on pinrestore, but you can find them anywhere. They were one size. Check my Fathom thread for some other options and ideas.

https://pinside.com/pinball/forum/topic/fathom-playfield-swap
F9BB1F90-ADD0-40E4-AD06-ADC920A3F080 (resized).jpeg

939B5944-BE9A-4F0F-AF13-F15BE459C0A4 (resized).jpeg

FB11344F-6AE6-4834-9E3D-06F62D839A78 (resized).jpeg

Glad it’s going to a good home. This was a labor of love, for sure.