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Steel vs Rubber vs Cast Iron Dumbbells

Steel vs Rubber vs Cast Iron Dumbbells

Nicollette Guido |

Steel vs Rubber vs Cast Iron Dumbbells

If you’re thinking about starting a home gym, dumbbells are some of the most essential pieces of equipment to have. They lend themselves to a wide variety of lifts, including chest press, dumbbell flys, shrugs, and bicep curls. In fact, a great HIIT workout or weight training routine is possible with dumbbells alone.

However, with so many dumbbells on the market, how do you know which type to choose? If you are wondering, “what weight dumbbells should I use?”, we can help guide you in the right direction.

Knowing what are dumbbells made of and the type of dumbbell to choose is paramount to hitting your strength and conditioning goals. This decision starts with understanding the differences between the three main types of dumbbell materials: steel, rubber, and cast iron.

#1 Steel Dumbbells

One of the most common types on the market today, steel dumbbells are a mainstay of many home gyms. They tend to be durable and rust-resistant, which means they can survive years of hard training.

Before breaking down the pros and cons of using steel dumbbells, let’s look at how they’re made.

Manufacturing Steel Dumbbells

Creating a set of stainless steel dumbbells begins with choosing a fixed dumbbell pattern. This means the weights are welded onto a metal handle and can’t be changed like other types of adjustable weights.

The following are popular dumbbell patterns:1

  • Hexagonal – Hexagonal (often called hex) dumbbells have end weights with six sides. This type of dumbbell is popular because its geometric shape prevents the dumbbell from rolling away from you. They tend to be longer than round and 12-sided dumbbells, which may increase the price.
  • Round – This dumbbell pattern has round weights at each end of the handle. Because of this, these dumbbells tend to be more comfortable when resting on your body between sets. The major downside is that, unlike hexagonal dumbbells, these dumbbells are likely to roll away from you if you put them down too fast.
  • 12-sided – Although 12-sided dumbbells look like round dumbbells, they’re actually curved very gradually so that each weight has 12 sides. As somewhat of a happy medium, these dumbbells tend to be more comfortable when placed on your legs in between sets, but they don’t roll away as easily as round dumbbells.

Once a pattern has been chosen, the next step of steel dumbbell manufacturing is attaching the steel heads to a steel handle. Some manufacturers use glue or cement, but welding the heads creates a more durable end product.

Advantages of Steel Dumbbells

As stated above, steel dumbbells tend to be durable and rust-resistant. This means they can withstand drops and outdoor or garage environments where most home gyms are located.

In addition, steel dumbbells boast the following advantages:

  • Aesthetics – Perhaps this is a matter of personal opinion, but most gym-goers would agree that steel dumbbells simply look better than rubber or cast iron. The steel is smooth and has that just-polished look that can make a home gym look and feel more professional.
  • Longevity – Because steel dumbbells are durable and more resistant to corrosion and rust, you can expect to use them for much longer. This often makes steel dumbbells more cost-efficient in the long run.

Disadvantages of Steel Dumbbells

The cost is the only major disadvantage of steel dumbbells. Because steel dumbbells are built to last a lifetime, you can generally expect to pay more for a high-quality set, especially if you’re looking into stainless steel. However, the price point naturally differs from one manufacturer to the next.

On average, you can expect to pay $12.88 for a five-pound chrome steel dumbbell and about $6.88 for a cast iron dumbbell of the same weight.2 This can certainly add up when you’re outfitting your home gym with an entire set of chrome steel weights.

Again, however, steel dumbbells are built to last a lifetime. Given the durability of steel, the upfront investment often pays off for any home-gym regulars.

The only other downside is that steel dumbbells can severely damage your floor if dropped. However, you won’t run into this problem if you’re lifting and lowering your weights gently.

For a solution that grants you the freedom to drop an occasional weight during an especially arduous set, you can find a rubber coated dumbbell that minimizes noise and potential damage to your floor and gym equipment while offering the same sought-after durability.

#2 Rubber Dumbbells

Despite the name, rubber dumbbells are made of metal. The difference is that the metal is then coated in rubber. When contemplating rubber vs cast iron dumbbells, this flexible coating can be a major boon—and occasionally a con.

But first, let’s briefly discuss how a rubber dumbbell is made.

Manufacturing Rubber Dumbbells

As stated above, a rubber dumbbell is first made by welding a metal weight to a metal handle, just like with steel or cast iron manufacturing. The metal is then coated in rubber. While some rubber dumbbells are fully encased, others have metal handles and rubber around the weights.

The dumbbell’s rubber can be made from the following:3

  • Synthetic rubber – Made from various chemicals, synthetic rubber is generally more durable than natural rubber. Synthetic rubber also tends to be cheaper to produce.
  • Natural rubber – Cultivated from the sap of various trees, natural rubber is more environmentally friendly than synthetic rubber. However, due to the cost of production, dumbbells made from natural rubber may be more expensive than dumbbells manufactured from synthetic rubber.

Advantages of Rubber Dumbbells

Rubber dumbbells come with a few advantages over steel and especially cast iron dumbbells. These include:

  • Durability – The rubber coating helps prevent severe damage to both the floor and the weights if dropped. What’s more, the rubber coating prevents rust and other types of corrosion. Finally, most rubber is also water-proof.
  • Acoustics – If you’re working out in a sound-proofed area, the clanking of weights may not be of much concern. But if you’re sharing a space with someone or working out in your poorly insulated garage, for example, the sound of metal on metal may become a serious annoyance. Fortunately, rubber dumbbells don’t clang when bumped together and are thus quieter than steel and cast iron.

If you’re looking for the best of the bunch, few dumbbells are better than Tru Grit’s hex rubber coated dumbbells. These durable, high-quality rubber dumbbells range from two to 15 pounds, making them the perfect choice for many types of workouts and fitness levels.

Disadvantages of Rubber Dumbbells

When deciding between cast iron dumbbells vs. rubber weights, we can’t ignore the potential disadvantages of rubber. These include:

  • Smell – While not a huge disadvantage, new rubber can carry a distinct odor. If you’re sensitive to smell, rubber dumbbells may not be for you. However, this odor does dissipate over time.
  • Cost – Rubber dumbbells can cost more than steel dumbbells, mainly because the price of the coating can fluctuate depending on the quality. And although they’re generally cheaper than cast iron, some rubber dumbbells can cost more depending on the brand.
  • Allergens – If you’re allergic to rubber or latex, these types of dumbbells are, unfortunately, not the right choice for you.

#3 Cast Iron Dumbbells

When most people hear the word “dumbbell,” they likely imagine a cast iron set in their mind. Cast iron dumbbells can either be fixed or adjustable and are noted for their durability and timelessness. They’re the oldest type of dumbbell.4

Manufacturing Cast Iron Dumbbells

Traditionally made with a short iron handlebar welded to two hexagonal or round weights, cast iron dumbbells are made by pouring melted cast iron into a mold cavity. Then, after the cast cools, the dumbbell is sanded, polished, inspected.

With an adjustable dumbbell, cast iron is used only to create the weights themselves, while another material is used for the handle. From there, the two are mounted together using screws.

Advantages of Cast Iron Dumbbells

When comparing cast iron vs. rubber dumbbells, there are several shared benefits across both, as well as a few areas where cast iron dumbbells have the slight upper hand:

  • Variety – The solid cast iron dumbbell can truly meet the needs of most weightlifters. Not only do they come in hexagonal, round, and 12-sided patterns, but they also come in a variety of weights and adjustable options.
  • Durability – Cast iron dumbbells are made to last. Unless you leave your dumbbells outside or consistently drop them, you can expect your dumbbells to last a lifetime.
  • Mass – An incredibly dense material, cast iron gives the proper feeling of weight. This “weightiness” helps stimulate muscle growth when used properly.

Disadvantages of Cast Iron Dumbbells

Cast iron dumbbells are a solid choice for many weightlifters. However, this type of dumbbell does come with a few cons, depending on your needs and expectations. These include:

  • Cost – Cast iron dumbbells tend to cost more than rubber dumbbells. Although prices vary considerably based on brand and weight, some cast iron dumbbell sets can cost thousands.
  • Damage – If handled with care, cast iron dumbbells should pose minimal risk to both yourself and your home gym. However, accidents do happen, and cast iron dumbbells have been known to cause significant damage, especially to floors (or feet). The best way to prevent chipped and cracked floors is to carefully lower your dumbbells when you’re finished using them.

Give It Your All With Tru Grit

Dumbbells are some of the most essential pieces of gym equipment to have when starting your home gym, but you want to ensure you make the right decision for your body, your workout routine, and your gym setup.

Should you buy hexagonal or round weights? Rubber dumbbells or solid cast iron?

Here at Tru Grit, we can help make your decision easier. From Hex Neoprene Dumbbells to Hex Elite Welded TPU Dumbbells, we have everything you need to make your workouts even better. For those fueled by passion and innovation, intensity and drive, there’s only one fitness company that lives up to expectations: Tru Grit.


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