What game is EE?
I've added a switch inside the coin return to add credits on my older sterns.

I don’t know what Bally EE is, but if it is an electromechanical machine, you can simply adjust one switch on the credit reel and the game will be in free play. You would still get a knock from a proper replay, but when the credit reel moves down to zero, the switch you adjusted will not change state, so the game still thinks it has credits on it.

Early Bally Solid states require a custom rom for free play. You can easily run wires from the coin switches to another switch. They outer coin slots are able to be set differently from the center slot so I usually use that center slot.

There is a company in Texas here on Pinside that sells a coin slot push button replacement, Third Coast I think.

found it https://pinside.com/pinball/market/shops/1041-third-coast-pinball

I don't see the button anymore. It would be an easy thing to make. Any momentary push button installed across a coin switch input would work. The button was installed in a stainless steel plate in place of the "insert coin" insert. It was nice because it was an easily reversible mod.

Yes.

Try this: Remove the left coin acceptor. Remove the coin micro switch from that side and reinstall it so that the trip wire is positioned just below the coin reject bar at the top of the removed coin acceptor’s bracket. I think you may be able to reuse an existing hole and you will just have to drill one additional hole. You can reuse the original #4 bolts from the coin switch. Now you will be able to use the coin reject button as a free credit button. The good thing is that this method is reversable and no cosmetic damage is done to the front of the machine. I hope I understood your question, if I didn’t just ignore me. If you need a picture let me know and I’ll upload one.

Still don't know what game you are talking about. Asking questions without telling us the game is akin to asking, 'need a brake line for a Ford' and not furnishing any other information.

Nice job Mageek! Rigging up a redundant coin switch behind the start button is a good idea. I used to do that with regular switch blades back in the day.
Some random inside triva for the group, back in the day I used to ask or get asked, why we didn't have a free play settings. The common response was, 'huh? why would a coin op game ever need free-play? Now go think up some new ways to re-purpose Pac Man!'

Alternatively, you can take the center coin switch wires (assuming unused - if not, any will do) and wire them straight to the switch in tandem with the existing switch wires. The common wire gets soldered directly to one switch lead, and the dedicated wire gets a diode in the middle before it heads to the other switch contact. This should coin up everytime you press start. I have all my Ballys wired this way. No extra parts needed, save a diode, and then perhaps a connector if you get fancy.

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My Paragon has the coin door lock replaced with an ugly red button to add credits.

I installed a switch in a square of aluminum cut to size replacing the center coin slot blank. The switch body fits through the hole already present for a light bulb and connects the spare wires meant for a center slot.

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Sorry to dig up this old thread. This is sort of what I just did on my EBD except I used the middle coin acceptor. I couldn’t figure out how to mount it so I used Velcro and a zip tie at least for the time being. The trip wire had to be bent a certain way so the switch would activate. Do you have a picture of how you mounted yours?
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Sorry to dig up this old thread. I tried this setup on my EBD but I just couldn’t get it lined up right. The micro switch wouldn’t register.

To use the coin reject button as a free play button. Try this: Remove the left (My choice) coin acceptor. Remove the coin micro switch from that side and reinstall it so that the trip wire is positioned just below the coin reject bar at the top of the removed coin acceptor's bracket. You should be able to reuse an existing hole and you will just have to drill one additional hole. You can reuse the original #4/40 bolts from the coin switch but you will have to tap the holes with a 4/40 SAE tap (The original 4/40 X 5/8" are not long enough to place nuts on them and a 4/40 x 1" bolts are generally not available at the local hardware store.) Install the bolt in the top hole first and tighten it in the desired position. Use a 3/32" drill bit and drill the second hole using the lower hole in the micro switch as a guide. Make sure you test the switch's operation before you drill the second hole! Remove the switch and tap the second hole. Reinstall the micro switch placing the top bolt in first but don't tighten it yet. Use an awl or similar sharp tool and push it through the lower hole to align it. Tighten the top bolt and then install the lower bolt. Now you will be able to use the coin reject button as a free credit button.
The good thing is that this method is reversible and no cosmetic damage is done to the front of the machine. Good luck.

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That's a picture of the switch installed on a Mata Hari. There was an existing hole that was conveniently located. I'll check an EBD tomorrow to make sure it has a similarly located hole. I've also done this on a Flash Gordon and EBD was made only 2 months after.

29REO, thanks for the pictures. I will try this when I get back from vacation next week. I’ll report back.

Finally got it done. Thanks 29REO. Works great and no more big yellow button on the door.

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