How to get inside a pinball machine and remove the glass above the playfield

Everyone who is new to pinball machines will have asked this question: how do I open a pinball machine ? How do I access the playfield underneath the glass ? How do I work on the bottom of the playfield ? How do I get inside the backbox ? How do I move the pinball machine ?

A pinball machine has 2 parts: a cabinet and backbox. Both of them are protected with a lock.

Read here how to open newer Stern games as they have a different design.

Open a pinball cabinet

coin door front

A cabinet has a coin door with a lock on the front. If you do not have a key, pick the lock or drill it open. You could use brute force, but this will damage the cabinet or door, so please don't do this unless you have no other choice.

Information about opening and picking locks can be found on this page.

Open the coin door and if you're lucky, the key to the backbox hangs inside on a little hook.
This can be on the coin door itself, or in the cabinet. Also check the cabinet, maybe the key is loose in there. (or screwed into the wood, which I've also seen)

key on hook inside coin door
The backbox key is where it should be, inside the coin door hanging on a metal hook.

How to remove the glass above the playfield

Once the coin door is open, at the top right there should be a handle. Pull this to the left, this will unlock the lockdown bar (which is the metal part on the front of the game above the glass, where you rest your hands on when playing the game).This lockdown bar goes out by pulling it straight up.

open door open door open door

Now you can slide the glass out. Be careful where you put the glass :-)

pf glass

Early 70ies Bally games have a different system. Games like Fireball and Nip-it have a metal frame which holds the glass. So the lockdown bar and siderails are one frame with the glass in, which you lift as a whole.

Gottlieb (sys80) and Recel have a metal handle on in the middle, instead of the right corner. This has to be pulled down to unlock the lockdown bar and playfield. Yes, it also locks the playfield. Even with the lockdown bar removed it's impossible to lift the playfield if this handle is in its original position.

How to lift a pinball playfield

First remove all pinballs from the game !! Then pull the playfield straight up at the metal arch (where pinballs disappear between the flippers). On old games you can slide the playfield a bit to the front and lean it to the backbox. Do not use the support rod, it's not secure, and as it only supports one side, your playfield will warp when it's up too long.

lift playfield lift playfield

Williams/Bally WPC games (after The Addams Family) use an improved system. First pull the playfield up. Then slide it towards you. It has a hook on each side of the cabinet which you will hear click into place. When the playfield is totally extended to the front, you can rotate it so it'll also stay up against the backbox.

lift playfield lift playfield

Some other types of games (like Williams system 11 and Data East) have another system. The playfield hangs in 2 pivot points. It isn't possible to pull it forward, you can only rotate it upwards against the backbox. This type of game is least fun to work on, as it's difficult to reach the end of the playfield.

How to open a pinball backbox

Old EM's have a metal plate in the back. It shouldn't be too hard to remove this, either drill the lock or put a screwdriver in it. From the back side you can unlock the backglass, it's held in place by metal pins.

remove backglass

Old Bally and Stern games have a lock on the top right side. This connects to a metal bar that goes over the backglass and keeps it in place.
Turn the key to the left and the metal bar will move against the glass. Turn the key to the right and the bar moves back, allowing the backglass to be removed.
If you don't find a key, drill the lock, but be careful that vibrations don't break the backglass !

How to remove a backglass:



  1. Lift the backglass about 2cm (1 inch) straight up (1), use the metal or plastic edge at the bottom.
  2. Now move the bottom of the glass towards you so it comes over the bottom edge of the backbox (2 - blue to red line)
  3. Now slide the backglass down so the top becomes available and you can take it out (3).

Note this system is the mostly used on games with backglasses and translights. Some games have a backglass in a wooden frame which opens (it has hinges on one side). Electronic Playmatic games use this for instance.

Williams games of the 80ies (Road Kings for example) have a lock on top of the backbox. Not very practical if you're in a low room (or a small person). Guess that's why they moved the lock on the recent Williams/Bally WPC games. Now the lock is in the middle above the translight, facing down. It is held in place by 2 security screws. So if you don't have a key, use a torx security bit (or a pair of pliers/vice grips) to remove the whole lock assembly.

Data East did the same as Williams, Playboy 35th i.e. also has the lock on top of the backbox, while later models also have it on top of the translight.

On my Gottlieb Bad Girls the lock is also at the top right side of the backbox. The key has to be turned to the left. This will unlock the whole top speaker grill assembly, this comes loose and then you can remove the backglass.

Once the backglass is removed, you see the backbox insert panel where lights and often scoredisplays are mounted on. Usually on the middle right side there's a metal clip that secures it in place. Just slide this upwards, and the whole panel can move, giving you access to the boards behind it.

backbox insert panel

backbox open