If you've ever played golf, then you're probably familiar with the term "golf ball." But have you ever wondered why they are called that?
Golf balls were originally made from a solid sphere of leather or stuffed feathers. They didn't have any holes in them at all. That makes sense because it would be hard to play a game with an object that was soft and squishy! Nowadays, golf balls are made out of rubber with little dimples on them instead of being completely smooth.
But how many dimples are there on a golf ball? And what's their purpose?
What are dimples on a golf ball?
Dimples are indented portions on a golf ball, which reduce the overall drag when the ball is in air. These dimples cause turbulence of the laminar (smooth) boundary layer flow around the curved surface of a spinning ball, making it unstable and asymmetric, so that its path becomes erratic and unpredictable.
As a result, there is an increase in the Magnus lift force of between four to five times.
Few people know how many dimples are there on a golf ball and what are their purpose. They help with the flight path of the ball, which may be curved in air depending upon its design and spin rate imparted to it by the golfer.
How many dimples are there on a golf ball
Most golf balls have between 350 and 500 dimples on their surface. The number of dimples ranges from the least expensive to the highest grade of golf ball.
The number of dimples on a golf ball affect the way it behaves when thrown. The more dimples there are on a golf ball, the less air resistance will occur when thrown through the air, and hence the ball's flight is more stable. This is often noticed by professional golfers who pick out different types of balls to use during play.
The dimples also cause the ball to get a truer trajectory when thrown, because of the thin layer of air that gets trapped between two layers of the golf ball.
The surface design also affects how far the golf ball will travel during play in comparison to its size. Golf balls with fewer dimples will naturally travel shorter distances than a ball with more dimples.
The number of dimples on a golf ball is also dependent upon the type of game being played. Golfers who are playing in windy conditions would prefer to use balls with as many dimples as possible. The golf balls with fewer dimples are ideal for use in calm weather conditions.
History of the dimple & Why do they exist
It was not until the late 19th century that golf ball manufacturers started putting dimples, also called "lacunar surface", on their balls. Manufacturers realized from past experiences with billiard balls and cannonballs that smooth balls did not fly well when thrown through the air. On both of these items, imperfections in the surface makes it easier for air to be trapped underneath, which would create lift. This and other information like tests done with tennis balls lead manufacturers to put dimples on golf balls to make them fly farther.
A number of different patents were granted for adding dimples, and sources vary on which company actually pioneered the idea.
The first patent was granted to William Taylor in England. The United States Patent Office has records of at least eleven patents before 1901 for golf ball dimples, with a number of them coming from John Boucher of New Jersey.
One method developed by Boucher involved cutting the ball out in different shapes and then filling the openings with smaller rubber balls. This was done by making a large ball out of rubber. It would be cut into the shape of the ball, and then filled with smaller balls, which were slightly less than half as big as it. The smaller balls would be pressed down to get them to fit in the holes carved out earlier. This process was patented on April 4, 1892.
A patent filed by Boucher on June 19, 1899 describes carving the balls out of a bigger ball and then gluing smaller balls into its surface. This process was patented on July 28, 1901.
Some sources say that an Englishman named Coburn Haskell developed dimples first, but there is no actual source for this information. A "New York Times" article from 1900, however, mentions that the United States Golf Association was asked to look into claims made by Coburn Haskell for a device that could be placed on a golf ball.
It appears that others may have developed dimples as well as Boucher... or at least had applied for patents before him.
A patent filed by William F. Hilleard and Charles Chambers on December 30, 1895 was also for a method of creating golf ball dimples using smaller balls to fill holes carved into a larger ball.
The above is not an exhaustive list of patents from the time period regarding this subject, but it does include some of the more influential ones that are mentioned by sources.
The question of who was first to develop the dimples remains controversial, but there is no doubt that it has been successful at least in part due to a patent on May 22, 1915 that was filed by Coburn Haskell specifically for this purpose and granted April 27, 1916. This begins an era where patents were more readily available to protect unique inventions, and where there was less "inventors' remorse" for filing patents.
The USPTO received a number of other patents for golf ball dimples after this date... but also granted some to others who had applied before Coburn Haskell. Sources do not explain whether or not the earlier applied for, but denied, patents were re-applied for to get a patent.
There is no doubt that these dimples do help the ball fly farther, and many golfers swear by them. One drawback though... they can make your shot go wildly off target if it hits anything other than smooth ground. That's probably why the USGA has strict rules about what dimples can be used on a golf ball. The rules are detailed enough that they include a table explaining how to calculate the allowed dimple area and another one for determining where they may or may not be placed.
During the era from 1939 through 1963, dimples were limited to 100 square inches of surface space, which meant that the total surface of the ball could not have been more than 1,300 square inches. This was determined by taking the diameter in inches and multiplying it by pi (3.14) then dividing that number by two to get the surface area. The rules were changed in 1963 so that golf balls did not exceed 1,700 square inches for total surface area, which meant that the dimples could be much smaller than they had been during World War II.
Other uses for the design of the dimple that may not be known about
The dimples on a golf ball affect the flight of the ball in many different ways, even though this is not immediately apparent to most people. Most importantly, they give lift to the ball when it was struck by a club.
This allows the ball to fly through the air much faster than if it did not have any dimples on it. This increases the distance that the ball can travel (without increasing its mass).
Dimples also affect how high the ball travels when hit. If you were to take a golf ball, and cut it in half down the center with a sharp knife, you would see that there is a small hollow at the core of the ball. This hollow is a perfect hemisphere, and is the reason behind the dimples on the ball. It serves to give more room for air to travel around the ball as it leaves the club.
The future of the design and how it is evolving with new technology
The design of a golf ball has evolved over many years and there are various companies that have made great advances in the technology involved. One such company is Titleist, which manufactures its product using a two-step process that involves molding and then forming.
There are many great things about the design of a golf ball, but most people do not even think about how the ball looks. The fact that there is an aerodynamic reason behind its design makes it even more interesting to people. It seems like such a simple thing, but it has had a profound effect on making the game more enjoyable for many people.
However, the basic concept of a ball with dimples that create lift while in flight has not changed, which makes sense because this allows the ball to fly without affecting its weight.
This is a great example of how the game has evolved in many different ways, but some things have remained constant over time.