How does the ball return operate on a coin-operated pool table?

If you've ever played on a coin-operated pool table at places like restaurants or arcades, you might have wondered, 'How does this table send the cue ball back to me?' Looking inside the table, you'll find a network of chutes connecting the six pockets. Each chute directs a pocketed ball to a collection area, where the numbered balls are lined up in a row. These balls remain locked in the chamber, visible through a piece of Plexiglas, until someone inserts coins to play a game. However, the cue ball can't be trapped in this chamber—if it's accidentally pocketed (a scratch), it needs to be returned to the player.

Table manufacturers had to devise a way to return the cue ball to play, while keeping the pocketed numbered balls securely locked in the storage chamber. Several ideas were proposed to address this challenge, including:

And so on. However, most coin-operated tables use two types of cue balls that are easily distinguishable:

The oversized cue ball has a diameter of about 2 3/8 inches (6 cm), which is roughly one-eighth (2 mm) of an inch larger than a standard ball. This small size difference allows the cue ball to be sorted before it enters the storage chamber. The smaller numbered balls pass through a gauging mechanism, while the bigger cue ball is directed down a separate chute, where it falls into an opening on the side of the table.

For players who aren't fond of the slightly bigger cue ball, there are coin-operated tables that use a magnetic ball instead. This ball has a magnet inside its core. When a magnetic cue ball falls into a pocket, a magnetic detector separates it from the numbered balls. As the magnetic ball passes through the detector, the magnet activates a deflection mechanism that redirects the cue ball, sending it to the side opening of the table.

Both the oversized and magnetic cue balls can be used interchangeably on most modern coin-operated tables, but each comes with its drawbacks. Beginners might not notice much difference when using the larger cue ball, but advanced players who are accustomed to the standard 2 1/4-inch cue ball might find it disruptive. Similarly, some players may perceive a difference with the magnetic ball, which sometimes lacks a consistent roll. Additionally, due to the embedded magnetic material, the magnetic ball is more prone to breaking if dropped on a hard surface.

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