How to avoid tilting a pinball machine
The first step towards becoming a pinball wizard is learning to physically manipulate the machine. Pinball is chaotic enough that no amount of skill will prevent the ball from heading towards the drain sooner or later. Even if you play a perfect game, eventually the ball will get stuck somewhere and you'll need to know how to get it out without tilting. The bumping, nudging and sliding techniques of pinball are numerous, but they all hinge on the ability to perform them without angering that delicate guardian of virtue known as the tilt sensor.
The tilt sensor in most pinball machines is simply a pendulum hanging in the center of a metal ring. When the pendulum hits the ring the tilt is triggered. All modern pinball machines will give you a couple warnings to burn before the tragic event comes to pass, so you can get a good feel for what kind hits it will take. A lot of factors can affect the sensitivity, not the least of which is the actual tilt setting as adjusted by the maintenance guy. That leads us to our first and most comprehensive technique:
Tell the maintenance guy the machine tilts too easy.
Half the time he'll be so amazed that someone actually still cares about pinball that he'll do it without even bothering to test first. The other half of the time he'll adjust it because he just doesn't care. Either way you can't lose... at least not if you know how to take advantage of the machine's newfound easy virtue.
Okay, so now that you have an unfair advantage, you must refine your bumping technique to the point of zen mastery. You may have noticed that there is usually some delay after the initial bump before a machine goes belly up. The reason for this is the same that a milk carton shoved violently onto the refrigerator shelf will slide to a halt momentarily before jolting forward again. When you initially bump the machine the inertia of the pendulum causes it to swing backwards, then just as its falling forward the rebound of the machine causes it to swing relatively higher in the other direction hitting the metal ring. The mechanism works so well because gravity affects both the machine and the pendulum equally (who said Newtonian physics was proven worthless by Einstein?). That leads us to our second and most impressive technique:
Do not let the machine rebound from a bump naturally.
This can be achieved in many ways, the easiest being to bump and hold for a second before releasing, giving the pendulum time to swing back all the way such that the rebound won't synchronize with the backstroke. You can also pull the machine back into place quickly before the pendulum gains momentum. In general, you tend to need to bump the machine a certain way to perform a save, with practice you can learn to perform an accompanying rebound action to prevent a tilt. If you are quite skilled, have good upper-body strength and pinball clairvoyance, there is a more subtle technique:
Muscle the machine slowly over to where you want it and then slowly let it back.
This works because often times the machine does not so much need a bump, but simply for the ball to not be heading straight down the drain. Because you're dealing with a round object, no matter how slowly you move the machine it will still move independently of the ball. A violent bump can only move the machine so far before the pendulum gains too much momentum. A slow move, however, can go much farther. A machine with wobbly legs is especially susceptible to this technique, and with a slight modification you can take it to infinite proportions. Behold, our final and most nefarious technique:
Attach casters to the front legs of the machine
I've never actually managed to do this, partially because I don't own any machines and partially because it would make pinball far too easy and hence boring. However, if you absolutely needed a high score on a difficult machine this would be one way to go. If you had a couple exceedingly thin casters you could probably stick them on a machine quite easily eithout disturbing the balance of the game too much. Any normal caster would require jacking up the back of the machine to level the play field. If you do sink to this level, please /msg me as I'd love to hear about it.