Tilt mechanisms on pinball machines

So you're playing a pinball machine, you're having a great game, you're getting excited, and suddenly: TILT!
What happened ?

The machine detected you were shaking it too hard and decided to punish you for it.
As pinball machines are coinop machines that are related to gambling machines, protections are built in to stop cheating.
Pinball machines are not gambling machines, but they still have protections: against damage to the machine, and to prevent players from cheating.

If the game is handled too hard, kicked, lifted, it will (slam) tilt so players can't continue playing.
The regular tilt will usually just end the ball in play. It's an indication to the player he's handling the machine too rough or trying to keep a pinball on the playfield that should've drained. Tilting the game is done to prevent a player getting too high scores. If you want to compare your high score against other people, it should've been set in comparable circumstances and not by preventing the ball from draining in illegal ways.

Tilt mechanism

One of these mechanisms is the classic tilt mechanism. It's usually found inside the cabinet on the left side, near the front of the game. The tilt is a metal weight that hangs on a rod and can swing around. The bottom part hangs inside a metal ring. If the weight hits the ring, an electronical circuit is closed and the machine detects the tilt switch as being closed.

Tilt mechanism on a 1950ies Gottlieb.

So what happens when you tilt ?
The flippers and rest of the playfield will go dead, the ball in play will be lost, and you will loose any bonus that was built up to be added at the end of the ball.
Older machines would immediately tilt on the first closure. On more recent machines you often get one or two tilt warnings, before the game will tilt your ball.

Tilt mechanism on a recent Stern pinball machine.

Adjusting tilt

The operator / owner of the machine can adjust how sensitive the tilt is. The conical weight is usually held in place with a screw (either through the weight or separate below it).
Lowering or raising it will decide how much the weight can move around before making contact, and thus decides how sensitive it is. As you can see in the pictures, my machines are set up very easy, but I'm also the kind of player that plays rather gently.

Does having a strict tilt mean you can't do anything as a player ? Do you have to handle your machine with white gloves and be very careful even when pushing the flipper buttons ?
Well, yes and no. It depends on the style of playing. How agressive do you push the buttons and keep moving the machine around ? It's normal that the weight will start to move around during gameplay, even an intense multiball can sometimes cause a tilt warning. But most people that start playing pinball are too gentle. It's ok to shake the pinball machine or to try to save a ball that's going to drain. Skilled pinball players can make impressive saves. One of the tricks if they slap the machine to one side to save a draining ball, is that they will immediately after slap the machine from the other side. This is to counter the tilt weight from moving around.

When setting up a game, take a look at the tilt mechanism and how the bottom ring is installed. Sometimes it's not correctly centered (especially if you put back legs very high and have a steep angle on the playfield). Then you may need to adjust the position of the ring so the weight hangs in the center and not towards a side.

Hint: always check that the game is levelled correctly. If one of the legs is extended a bit too much then the game doesn't stand firm but will slightly move around during gameplay. This will cause the tilt weight to be constantly in motion, making it more sensitive to tilt during gameplay.

Slam Tilt

Most pinball machines also have a slam tilt switch on the inside of the coin door. It's a leaf switch with a weight on it.
If you kick the game from the front side with your knee or foot (out of agression because a ball drained, or when trying to kick a pinball that went below the flippers back into gameplay), the game will slam tilt. That's game over, immediately.

Other tilt mechanisms

Older games (before the 1990ies) sometimes had another type of tilt mechanism: a pinball that's inside a metal frame. If you lift the front of the pinball machine up in the air (to get pinballs on the playfield, change how they roll, or out of agression to drop the machine), the pinball will roll to the end of that frame and there make contact with a switch and slam tilt your game.

Tilt on a Bally Fireball.

This Zaccaria Pinball Champ 82 has 3 types of tilt.

Historic tilt mechanisms

The very first pinball machines had other types of mechanisms to indicate if the game had been handled too hard.
This machine from 1936 has a metal ball that's raised on a post at the beginning of a game. If you shake the game too hard during gameplay, the ball will fall off. There was no electronic system to detect this, it was just visual. As long as the ball was still on the center post, your score would be valid (and be used for a payout).