Welcome to brain Stuff from house starks dot com where smart Happens. Hi, I'm Marshall Brain with today's question, how does the ball return work on a coin operated pool table? If you've ever played one of those coin operated pool tables in a place like a restaurant or an arcade, then you know that the obvious question is how the heck does this thing return the cube all to me? If you look inside the table, there is a system of shoots that connect to all six pockets on the table.
Each shoot sends a pocketed ball from the pocket to a collection chamber where the numbered balls are lined up in single file. These numbered balls remain locked in the chamber, which you can see behind a piece of plexiglass, until someone wants to play a game and insert some coins. Of course, the cue ball can't get stuck in this chamber. If a player accidentally pockets the cue ball, called a scratch, the cue ball needs to come back out so the
players can continue playing. Table manufacturers needed a way to allow the cue ball to be returned to play while keeping the pocketed numbered balls locked in that storage compartment.
Many solutions have been proposed to solve this problem, including light sensors that since the light reflected from the que ball, a metallic core ball that would trigger a separating mechanism when it passed through an electromagnetic field, a balanced mechanism that would separate a heavier cue ball from lighter number balls, and so on. For the most part, though, coin operated tables used two types of que balls that can be
easily separated. The first is an oversized ball that can be separated by the radius of the ball using a radius gauging device. The second is a magnetic cube ball that triggers a magnetic detector. The oversized ball is approximately two and three ace inches or six centimeters in diameter, and it's about one eighth of an inch or two millimeters larger than a normal ball. This slight difference in size allows the cube ball to be separated before it
gets to the storage compartment. The smaller numbered balls are able to pass through a gauging mechanism, while the larger cue ball is directed through a second shoot where it falls out into an opening on the side of the table. For players who dislike using a slightly larger cue ball, there's also coin operated machines that can use a magnetic ball in which a magnet is built into the core
of the cue ball. Magnetic cue balls that go into a pocket are separated from number balls by a magnetic detector. As the magnetic ball passes this detector, the magnet triggers a deflecting device that separates the cue ball and again sends it into an opening on the side of the table. Both the oversized and magnetic cubeballs can be used interchangeably on most of today is coin operated tables, but each
has its shortcomings. If you're a beginning pool player, the larger ball might not affect your play, but it can disrupt the play of some advanced players who are used to playing with the normal two and a quarter inch cue ball. Likewise, some players will notice the difference in the properties of a magnetic cube ball, which sometimes lacks
a true role. Also, because the magnetic cubeball has a magnetic material inserted into it, it has a greater tendency to shatter if you drop it on a hard floor. Be sure to check out our new video podcast, Stuff from the Future. Join How Stuff Work staff as we explore the most promising and perplexing possibilities of tomorrow. The house Stuff works, I Find app has a ride down at it today on iTunes