(Topic ID: 292750)

General Question: Contact cleaning


By Wizbangdoodle

11 days ago

Topic Heartbeat


Topic Stats

  • 12 posts
  • 6 Pinsiders participating
  • Latest reply 10 days ago by Wizbangdoodle
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You

Linked Games

#1 11 days ago

Ok, I'm a noob, as I've just purchased my first 2 pins. I'm already experiencing a few problems and was looking into cleaning contacts. I started by reading through the stickies at the top of the forum, followed some links and have a good idea how to proceed.

My question is: How do you tell the difference between contact types? From what I've read, each material type takes a little bit different cleaning.

#2 11 days ago
Quoted from Wizbangdoodle:

How do you tell the difference between contact types? From what I've read, each material type takes a little bit different cleaning.

Solid state games usually have contacts you clean by putting a piece of paper between the contact points, gently hold closed and pull the paper out. So you don't sand or wear of the plating. With the exception of flipper button leaf blades and EOS switches until the fliptronics era. Those burn, you can see if on used ones. Blades are tungsten and meant to be filed.

EM games are higher power and can be sanded or filed.

https://www.pinballlife.com/williamsbally-flipper-leaf-switch-double-contact.html look at this leaf blade switch, the kind of silver covered part of the contact is tungsten.

LTG : )

#3 11 days ago

This forum is full of posts from people who tried shotgun cleaning & adjustments, and caused more problems than they were originally trying to solve.
What to do instead: Slowly and carefully diagnose one problem at a time and then fix only that.
http://www.pinrepair.com/em/index2.htm#clean

#4 11 days ago

Haven't seen that macro in awhile

#5 11 days ago

With EMs the silver oxide that forms on switch contacts is actually a very good conductor so it is better to only file them once you have identified them as being suspect for a specific problem. Especially switches that are only lighting lamps which aren't really going to have any burning due to arcing. Making sure the stack screws are retightened first (they dry up with time and can become loose) and then checking the gap is much more important.

#6 11 days ago

And that brings up another question, frenchmarky. Gapping. I've read a lot about how it needs to be done, but really didn't pick up on how you know when it's correct.

I've got so much to learn.

#7 11 days ago
Quoted from Wizbangdoodle:

how you know when it's correct.

It works.

LTG : )

#8 11 days ago

Yeah adjusting them isn't something you want to do with every switch in the game either, don't do it unless you have a problem or you'll get them all out of whack. Tightening up the stacks if they need it helps put them back to where they should be anyway unless someone else happened to has messed with a particular switch before you got the game.

#9 11 days ago
Quoted from Wizbangdoodle:

but really didn't pick up on how you know when it's correct.

It's difficult to tell by eye if the switch is adjusted correctly. They may look like they are closed but may not be conducting. A switch has a long contact that moves when the white plastic actuator plate moves to either contact the shorter blade (NO - normally open) or pull away from it (NC - normally closed). When you activate the relay by hand, an open switch will close and a closed switch will open. The smaller blade will not only make or break contact but will also move slightly when the longer blade touches or pulls away from it. That "overage" insures that the blades make good contact and wipe across each other to clean oxidation off the switch.

#10 10 days ago

Thanks hjh, that makes sense. A bit different than the ice cube relays I deal with in CNC machines.

And now my Space Mission is acting up. Tilted during a game and now it will only score 100's. Just keeps rolling over to all zero's when it reaches 1000. Chimes aren't working on most things either. Things are going downhill fast. Oh well, ordered some tools and will dig into it after they arrive.

BTW, anyone know where I can get schematics for my Space Mission?

#12 10 days ago

You guys are awesome. Thanks HowardR.

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