To the untrained eye, a roulette wheel features as an all-in-one mechanism. Upon closer examination, it is clear that the wheel is comprised of two components. The first is the inner section of the roulette wheel known as the wheelhead. 


Components of the Roulette Wheel

This part of the wheel rotates around a central shaft known as the spindle. This has to be precisely perpendicular to the table to ensure a perfectly balanced wheelhead. The wheelhead also goes by another name, the cylinder. A series of alternating red and black numbers adorns the wheelhead, including the green zero for European Roulette and French Roulette, as well as the the green 00 for American Roulette.
The outer section of the roulette wheel is known as the bowl. It can be thought of as the housing for the roulette wheel. For the most part, the bowl is made of solid wood, but the surface can be plastic, epoxy, or a veneer. Since the wheelhead is perfectly encapsulated within the bowl (and is removable), the bowl also contains several important components of the roulette wheel mechanism. These include the lower ball track apron, including the ball deflectors, as well as the spindle mechanism. The ball deflectors are sometimes known as diamonds, and they are positioned to disrupt the roulette ball’s trajectory around the bowl. This adds a degree of randomness to the outcomes.
The inner component of the roulette wheel – the wheelhead - fits snugly into the bowl. It typically measures a diameter of 20 inches, and is fixed in place with ball bearing assembly components. Recall the alternating red and black roulette numbers? These are found on the outer rim of the inner section of the wheelhead. The outer lip of the roulette numbers circle is raised (slanted upwards) to dovetail smoothly with the bowl. Notice the central cone that rises towards the turret in the center of the roulette wheel? This is intentionally convex so that the ball will ultimately fall into one of those numbered slots on the roulette track.

Table of Contents

•    What is the Roulette Ball Made of?
•    How Important are the Roulette Ball Deflectors?
•    The Components of Roulette Pockets
•    What is a Biased Roulette Wheel?
•    American Roulette Wheel
•    European Roulette Wheel
•    French Roulette Wheel 
•    What about a Roulette Wheel Online?
•    What is a Roulette Wheel Spinner?
•    How to Play Roulette Games Online?
•    How to Win Roulette Games?

What Is the Roulette Ball Made of?

In the days of old, roulette balls used to be made from ivory. Of course, this practice has long since been outlawed since casinos do not support the killing of elephants for ivory. Many governments around the world have outlawed this practice too. Nowadays, roulette balls are known as Ivorine, meaning that they look like they're made from ivory, but they are made from a synthetic substance. Over the years, roulette balls have been constructed from all sorts of different compounds, notably ceramic, nylon, acetal, phenolic, Teflon, and resin. It is worth pointing out that the composition of a roulette ball has an obvious effect on the game of roulette. Weight, density, dimensions, bounce and traction are affected by the composition of the roulette ball.
Consider the implications of a lightweight roulette ball made from a plastic-style substance as opposed to a denser roulette ball with bigger dimensions. Lightweight roulette balls typically bounce around a lot before coming to rest in one of the numbered pockets. The lighter balls – typically made from nylon - move around the roulette wheel track many more times than the heavier, denser balls. The unpredictability of lightweight roulette balls is another factor to consider. Roulette players seeking to gain advantage from an understanding of the mechanics of roulette wheels and their components will certainly benefit from appreciating the importance of roulette balls on outcomes. 
By and large, roulette balls are proportional with the diameter of the roulette wheels. Large wheels typically measure 27 inches, 30 inches, and 32 inches. The roulette ball diameters will routinely measure 18 mm on the small end and 21 mm on the large end. However, many casinos use roulette balls with diameters measuring 13 inches – 16 inches. Casinos alternate ball usage to enhance the unpredictability of the game as well. The short and sweet of it is as follows: heavier roulette balls settle rapidly, while lighter roulette balls bounce around a lot more.

How Important Are the Roulette Ball Deflectors?

The roulette ball deflectors are known as diamonds. They resemble diamonds in appearance, and are glued or screwed into the outer part of the roulette wheel known as the bowl. The diamonds are typically silver in color, but they could be gold too. The diamonds are evenly spaced, with horizontal and vertical diamonds appearing on the bowl. Their purpose is clear: disrupt the roulette ball's motion around the track to ensure the most unpredictable outcome possible. 
However, there are complications with regards to roulette ball deflectors a.k.a. diamonds. Some of them actually bear the brunt of the ball’s motion, and become known as dominant diamonds. This means they are subject to the abrasive effects of the ball continually brushing up against them. When diamonds are classified as dominant diamonds, they are typically worn down, scratched, cracked, or uneven. A roulette aficionado might attempt to take advantage of such a phenomenon.
The implications of dominant diamonds are clear: greater predictability of outcomes. However, modern day casinos across Atlantic City, New Jersey and Las Vegas, Nevada routinely switch out roulette wheels to ensure that dominant diamonds do not play a part in roulette wheelspin outcomes. The key to understanding dominant diamonds is the release point of the roulette croupier. If the ball is released at or near a specific set of numbers on the wheel (known as quadrants) it becomes more predictable to determine what potential outcomes may result. 
This is more of a crapshoot than a logical science, since there are multiple variables that come into play at the release point, such as traction, force, foreign substances, atmospheric variables, static electricity, air pressure, temperature, and myriad other considerations. Suffice it to say, worn roulette ball deflectors can play a part in ascertaining quadrants where the ball may land.
On the topic of roulette ball deflectors and roulette balls, it is worth highlighting that modern-day roulette wheels – the new designs – don't have a lip. The lip is located between the apron and the concave circumference where the ball spins. The lip makes it easier to predict where the ball is going to come to rest. Without the lip in place, predictability is greatly diminished. With the newer tracks, there is no obstruction to the ball rotating around the track.

The Components of Roulette Pockets

In layman's terms, the roulette pockets are the areas of the roulette wheel where the ball comes to rest. Naturally, each pocket represents a single roulette number. The pockets where the roulette ball lands are important insofar as they represent winning numbers, and payouts. Believe it or not, roulette pocket designs and features are not uniform. Casinos routinely change the structure of roulette pockets for greater unpredictability. At inception, many roulette wheels featured deep pockets. These would have high walls between the numbers. 
The impact of deep pockets is less bounce, and greater predictability. Of course, there are many factors playing into the bounce and predictability equation. These include the stability of the pocket separators themselves. If they are loose, they tend to absorb impacts with the ball and reduce the motion of the ball, causing it to come to rest much quicker. When the pocket separators are firmly attached, they tend to repel the ball with equal and opposite force, leading to variability of outcomes. From a player's perspective, it's impossible to know whether the pocket separators are loosely attached or firmly attached without conducting careful and methodical research of outcomes.

What Is a Biased Roulette Wheel?

Every roulette player hopes to encounter a biased roulette wheel. In reality, land-based casinos work diligently to ensure that any imbalances in roulette wheels are immediately corrected. In the days of old, biased roulette wheels were common at casinos, since scant attention was paid to worn frets, or imperfectly positioned wheelheads, degraded tracks, or manipulated roulette balls et cetera. Today, every component of a roulette spin is closely monitored by casino management, and security personnel. 
A biased wheel tends to generate predictable results, although specific outcomes are improbable. What generally happens with a biased roulette wheel is that the ball tends towards certain quadrants of the wheel. This can only be determined over time, over hundreds, or thousands of spins. Since every number has an equal chance of coming up on any given spin, biased roulette wheels tend to generate outcomes that defy the random outcomes nature of the game.
Manipulation on the part of the roulette croupier is difficult, but not impossible. Provided a legitimate roulette ball is used, and there is no interference with the ball’s motion around the track, the only way to manipulate outcomes is by placing foreign substances on the wheel track, replacing the roulette ball with a biased ball, intentionally sabotaging components of the roulette track, or using gadgets and gizmos to control wheelspin outcomes. 
Today's roulette wheels are manufactured with absolute care and precision. They subscribe to the highest standards of gaming excellence, as determined by the regulatory authorities within which the casinos operate. Expect zero-defect roulette wheels at every reputable casino and online casino that you play at. For players on a mission to uncover biased roulette wheels, it would take several thousand spins to spot any discernible patterns – a feat that most players will not undertake.
Consider the case of Joseph William Jaggers from the 1800s. This English engineer specifically looked for imperfections in roulette wheels in Monte Carlo. He realized that a high probability of winnings could result if he was able to pinpoint a set of numbers that were more likely to come up than others. He paid 6 assistants to watch and document the outcomes of the roulette wheel spins for one month. Lo and behold, the biased roulette wheels were going to pay off big time for him. 
What he then proceeded to do was to place outsized bets on the numbers that came up more than others. Within a few days, he had amassed a total of $325,000, which amounts to several million dollars in today's dollars. By the time the casino realized what was going on, he was long gone and living large. Similar feats have been undertaken by students from notable universities like Berkeley in California. Naturally, casinos are one step ahead and routinely switch out their roulette wheels to prevent what they call long run frequency bettors from identifying patterns and trends.

American Roulette Wheel 

The American Roulette Wheel is unique. It features 38 numbers around the roulette track, including 0, 00, and numbers 1-36. The roulette wheel layout comprises a configuration of alternating red and black numbers as follows: 0-28-9-26-30-11-7-20-32-17-5-22-34-15-3-24-36-13-1-00-27-10-25-29-12-8-19-31-18-6-21-33-16-4-23-35-14-2. The numbers do not follow any specific pattern; it is intentionally designed this way to prevent any form of predictability. 

This sequence of numbers has no bearing on the outcomes of roulette spins. If you look closely at the American Roulette wheel, you will see that numbers tend to correlate on opposite ends of the wheel. For example, 0 is directly opposite from 00, and 2 is directly opposite from 1, and 30 is directly opposite from 29. Believe it or not, the sum total of roulette numbers on the wheel is 666 – The Devils’ Number. This is the same for American Roulette, French Roulette, and European Roulette, since the only differences between these games are the zeros.
*The house edge with American Roulette is 5.26%, with a corresponding RTP of 94.74%

European Roulette Wheel

European Roulette wheels are also known as single-zero roulette wheels. As its namesake suggests, there is only 1 green zero on the roulette wheel. However, that dramatically changes the configuration of numbers around the European Roulette wheel. The roulette wheel layout is as follows: 0, 32, 15, 19, 4, 21, 2, 25, 17, 34, 6, 27, 13, 36, 11, 30, 8, 23, 10, 5, 24, 16, 33, 1, 20, 14, 31, 9, 22, 18, 29, 7, 28, 12, 35, 3, 26. All in all, there are 37 numbers, including 0, and numbers 1-36. There are 18 black numbers and 18 red numbers, as well as a green 0. You will generally find that the sequence of numbers in European Roulette games is standard across the board. Only in very rare cases with customized roulette wheels will you see a different sequence of numbers on the European Roulette wheel.

*The house edge with European Roulette is 2.70%, with a corresponding RTP of 97.30%.


French Roulette Wheel

French Roulette wheels are popular across continental Europe, notably in France, Austria, Germany, Switzerland, and the UK. It is similar, almost identical, to the European Roulette wheel with alternating red and black numbers. The difference comes in the actual layout of the roulette betting track on the table. The number sequences are referred to as the French number sequence. All of the French Roulette bets are written in French – another notable difference between this single zero roulette game and European Roulette. Owing to the special rules of French Roulette, the house edge in this game can be as low as 1.35%, courtesy of the En Prison Rule and La Partage. Read more about the rules of French Roulette at our online casino blog.

What About a Roulette Wheel Online? 

Contrary to popular belief, the online roulette wheels you see at your favorite online casino are not actually real roulette wheels. They are merely graphical displays of complex algorithmic programs known as random number generators. The animated roulette wheel that you see spinning on your screen is perfectly synchronized with the outcomes of the random number generators (RNGs). 
Think of it like an animated application that mimics your speech and facial features on your mobile phone. The only thing that's important with roulette wheels online is the RNG. This is the randomizer which guarantees fair outcomes on every spin. Of course, game developers put tremendous time and effort into crafting beautiful roulette wheels online for maximum engagement, immersion, and entertainment value. However, the actual results are determined by chance alone.

What Is a Roulette Wheel Spinner?

A Roulette Wheel Spinner is a rudimentary tool which spins a virtual wheel to generate a random outcome. Savvy developers can easily create these types of online roulette wheel spinners with JavaScript and with audio APIs. JavaScript is not necessarily needed for these roulette wheel spinners. Audio files lend additional realism and functionality to the programs, giving the satisfying click and dropping sounds that players have come to expect from roulette game results. The objective is to generate a truly random set of outcomes, with thousands of values being added to the roulette wheel spinner.
In much the same vein, roulette wheel simulators are readily available. These are rudimentary roulette games available to players for free. It is a simulation because it mimics what a roulette wheel would do. With Roulette simulators, you get the same results as you would with demo play roulette games, or free roulette games online. Roulette simulators are typically available at online casinos in the form of demo roulette games, but not at land-based casinos. If a player wins in a roulette simulator, it doesn't mean that you win real money. It is simulated winnings with faux money.

How to Play Roulette Online?

Online roulette games are just as easy to play as land-based roulette games. The difference is the 3Cs: comfort, cost, and convenience. With online roulette, you must first register at a New Jersey online casino, verify your ID and location, and then safely deposit funds into your account. You can play online roulette for real money, or for free. Simply select your bet size by clicking on the desired chip value. Place the chips on your preferred bet selections. It's a good idea to read our guide on how to play roulette before you switch to real money online casino games. Recall that French Roulette has the lowest house edge at 1.35%, followed by European Roulette at 2.70%, and American Roulette at 5.26%.
It's always a good idea to play roulette free online before you play for real. That way you get to test all your roulette tactics and roulette strategies in real-time, using the casino RNGs to mimic real-world outcomes. When choosing between different roulette variants, pay special attention to the minimum and maximum bets, roulette rules, and return to player percentages. Online casino roulette games mirror what you will see at bricks and mortar casinos. Provided the online casino games are independently tested and audited for randomness, there is no reason not to play roulette online. The regulatory and oversight authorities include the likes of iTech Labs, Technical Systems Testing, and eCOGRA Safe and Fair, among others. Full licensing and regulation is a requirement before you play online roulette.

How to Win Roulette Games?

Roulette is a numbers game. Online roulette and land-based roulette function along similar principles. Your goal is to place your choice of inside bets or outside bets, in the expectation of the roulette ball landing on that pocket, color, number, or selection. Once you land a winning result, you get paid out according to the roulette rules. The highest payouts are applicable to straight up bets on individual numbers. Even money bets pay 1:1 for options like red or black, odd or even, 1-18, or 19-36. Careful bet selection is necessary if you wish to increase your chances of winning. For this, outside bets are preferable to inside bets, since the frequency of winning is much higher, but the overall payouts are much lower.
Online casinos routinely offer roulette bonuses and promotional offers. As a new player, you're privy to a welcome bonus package which may include a no deposit bonus. This can be used to boost your bankroll in anticipation of real money gaming. Be advised that all welcome bonuses are subject to wagering terms and conditions. This means you will need to bet a pre-set amount (typically the bonus + deposit amount) a certain number of times before you can cash out any of the winnings generated from the bonus. The information provided on roulette wheels in this guide can be used to great effect at land-based casinos and online casinos. Despite our best efforts at unravelling the mysteries of roulette, it remains a game of chance with the casino holding the upper hand over the long-term.

About the Author

With digital marketing strategies in his blood, Louis Wheeler has traveled around the world, exploring gambling cultures and gaining experience in casino games from 2003. If you are in a casino anywhere around the planet, you may find him right next to you, playing blackjack, roulette or texas hold'em.