Golf Ball Mechanics 101

Manufacturers are investing a great deal of time and money in research and development. They look to optimise the physical shape, construction and materials for enhanced ball performance. Given our dedicated to discussions and comparison of golf balls, we thought it useful to go over some of their mechanical properties. We wanted to provide you some general information to help you better understand how each of these dimensions can impact the overall performance of the golf ball. Hopefully our Golf Ball Mechanics 101 will do just that.

The Cover

If you pick up a sleeve of balls you will notice creative terms and trademarks regarding their ball cover materials. While each may have their own formulas, the actual covers can be broken down into two main materials


Ionomer is defined as a class of tough synthetic ethylene-based thermoplastic resins consisting of a copolymer. It is a low cost hard surface material that is very durable. Balls with ionomer covers are particularly good for long-distance play and with their spin resilience they are more typically resistant to hooking and slicing the ball. 

While there are many Ionomer materials now in use the most popular ionomer material is Surlyn, a specific type of plastic ionomer manufactured by DuPont. Surlyn is extremely durable to cuts and scuffs. While the limitations on spin and feel in the Ionomer cover may make it a good ball for Mid to High handicap players lower handicap players look for higher performing materials


Urethane is a polymer which can be controlled when heat is applied. This allows manufactures the means to influence the hardness/softness of the material. It is softer than Surlyn and yields higher spin rates on iron and wedge shots. This translates into more control and a better feel when putting and chipping. 

Depending on the compound and ball construction Urethane may lose some distance compared to Ionomer. Manufacturers have been able to mitigate the decrease by using multiple layers in the construction of the ball increasing the its performance. Due to the complexity of all these processes urethane covers are generally more expensive

Number of Pieces

It may be easier for some to conceptualize the number of pieces of the golf ball by thinking of the number of layers in of the earth. If not the just stick to thinking about the golf ball. The number and composition of the layers change how the ball reacts and travel when struck by the club. It also directly impacts how the golfers feels the balls hardness during contact.

Since we have long since moved on from using 1-piece balls so we will begin our discussion with:

2-Piece Golf Balls

Two Piece balls are limited to a core and a cover. With their lower manufacturing costs, they are often the choice of less experienced golfers. As mentioned, Ionomer covers are more common on 2-piece balls. Ionomer generates less spin and is firmer than urethane. Thus it allows beginner golfers to generate high ball speeds resulting in greater distances while keeping the ball straighter.

3-Piece Golf Balls

Three-piece balls consist of a core, mantle and cover. The extra layer coupled with either an Ionomer or Urethane cover increases the softness and spin potential of the golf ball. The construction of the individual layers aims at isolating ball behavior at specific situations on the course. For example the behaviour off the tee compared to using a pitching wedge.

4-Piece Golf Balls

Four-piece golf balls come with a dual core, middle cover and cover. The extra cover usually is designed to help generate additional distance from the tee while the dual cores construction is aimed at optimizing short game spin. 4-piece balls are almost always paired with a Urethane cover. Their complex manufacturing process is usually linked to a premium priced golf ball.  To optimize the benefits they generally require greater swing speeds and club control making them more suited to experienced golfers. 

5-Piece Golf Balls

Take everything I mentioned about the four-piece golf balls and then add some. There are limited numbers of balls on the market using a 5-piece construction and much like the four piece ball are geared towards the experienced golfer.


There are usually somewhere between 300 to 500 dimples on a golf ball. The number, shape, depth and pattern of these dimples drastically changes the behavior and flight of the golf balls and how air moves around it. To quantify, a golf ball without dimples would travel approximately 50% less distance than a dimpled ball. 

Due to the complexity of interconnecting variables there is no definitive answer as to the perfect number of dimples. Moreover, since the surface area of a golf ball is a constant, changes to the number of dimples will immediately impact the size and depth of each individual dimple.