Aluminum Boat Thickness: How Thick Should It Be?

When it comes to boats, aluminium is a popular choice for fishing and recreation. The thickness of an aluminium boat is an important consideration, as it can affect factors such as comfort, durability, and performance. Thicker aluminium boats tend to provide a smoother ride and are more durable, while thinner boats may be lighter and more fuel-efficient but could require special care and be more susceptible to dents and damage. The thickness of aluminium boats can vary, with bottom thicknesses ranging from 0.1875 inches to 0.250 inches, and side thicknesses of around 0.190 inches. When choosing an aluminium boat, it's essential to consider factors such as intended use, weight, thickness, and alloy type to ensure the boat meets your specific needs and provides a safe and enjoyable experience on the water.

Aluminium boat weight and thickness

The weight of an aluminium boat depends on several factors, including its length, engine size, and type. Let's take a closer look at the weight and thickness of aluminium boats, with some examples for context.

Jon Boats

Jon boats are a common type of aluminium boat, known for their flat bottoms and shallow drafts, making them ideal for fishing. The weight of a Jon boat depends on its length. A 10-foot Jon boat can weigh as little as 130 pounds (59 kg), while a 20-foot boat can weigh over 1,200 pounds (544 kg). The average weight of a 14-foot to 16-foot Jon boat is around 525 pounds (238 kg), excluding the engine. The engine weight for this size ranges from 15 hp to 30 hp, adding about 115 pounds to 165 pounds (52 kg to 75 kg).

Deep V-Boats

Deep V-boats are another popular type of aluminium boat, known for their wedge-shaped hulls, which provide good performance in large bodies of water or oceans. An 18-foot Deep V-boat typically weighs around 1,500 pounds (680 kg) without the engine.

Bass Boats

Bass boats are designed specifically for fishing, with features like coolers, livewells, and swivel seats. An 18-foot bass boat normally weighs around 1,200 pounds (544 kg).

Multi-Species Boats

Multi-species boats, as the name suggests, are designed for fishing various types of fish. An 18-foot multi-species boat typically weighs about 1,000 pounds (453 kg).

Thickness

When it comes to thickness, aluminium boat bottoms can vary. Some boats may have a bottom thickness of 0.1875 inches, while others may have a thickness of 0.250 inches. A heavier-duty aluminium boat may have a bottom thickness of 1/4 inch (0.25 inches or 6.35 mm). This thickness is considered standard for boats over 20 feet in length.

The thickness of the aluminium bottom can impact the boat's durability, ride comfort, and corrosion resistance. A thicker bottom is generally associated with better performance and a more comfortable ride, especially in choppy water conditions.

In summary, the weight and thickness of aluminium boats vary depending on their type, length, and specific features. Thicker aluminium bottoms typically provide better durability and ride quality, while the length of the boat is a significant factor in determining its overall weight.

Boat floor thickness

The thickness of a boat floor is an important consideration when building or buying a boat. While there is no definitive answer to the ideal thickness, as it depends on various factors such as intended use and personal preference, here is some information on boat floor thickness to help guide your decision-making process.

Firstly, it is essential to understand that the thickness of a boat floor is typically measured in inches or fractions of an inch. Common thicknesses mentioned in forums include 1/8", 3/16", and 1/4". Thicknesses below 1/8" are also used but may require additional support or reinforcement to ensure sufficient rigidity.

When considering the thickness of your boat floor, it is crucial to take into account the intended use of the boat. For example, if the boat is primarily for lake fishing and recreation, as mentioned in one forum post, a lighter boat may be more attractive for towing, handling, and fuel economy. However, a heavier boat with a thicker aluminium bottom is likely to provide a smoother ride and may be more durable, especially when navigating waves.

The spacing of the supports underneath the boat floor is another critical factor influencing the required thickness. According to one forum user, with support spacing of 2 feet, a thickness of 3/16" is recommended. Another user suggests that with this spacing, a thickness of 1/8" would be sufficient if combined with dense foam underneath the aluminium to add rigidity and take any sag out of the floor.

Additionally, it is worth noting that while thicker aluminium will generally provide more durability and rigidity, it also adds weight and cost to the boat. As such, it is essential to consider the trade-offs involved and decide which factors are most important for your specific needs.

Finally, when making your decision, it may be beneficial to seek advice from boat manufacturers, experts, or experienced boaters. They can provide insights based on their knowledge and experience to help you choose the optimal thickness for your boat floor.

Boat hull thickness

When it comes to aluminium boat hull thickness, there are a few key factors to consider. Firstly, the intended use of the boat plays a significant role in determining the ideal hull thickness. For example, a boat intended for river use may benefit from a lighter hull for improved manoeuvrability and fuel efficiency, while a boat intended for offshore or choppy water conditions may require a heavier and thicker hull for better durability and ride comfort.

The weight and thickness of the hull can have a significant impact on the boat's performance and handling characteristics. A heavier boat with a thicker hull, such as one with a 0.250" bottom thickness, will generally provide a smoother and more comfortable ride, especially in rough waters. Thicker hulls also tend to offer better durability and corrosion resistance. On the other hand, a lighter boat with a thinner hull, such as one with a 0.1875" bottom thickness, may be more appealing for towing purposes and can offer improved fuel economy. However, thinner hulls may be more susceptible to dents and damage from rocks or other obstacles.

The design and construction of the hull should also be considered in conjunction with thickness. The number and arrangement of frames, stringers, and supports can significantly impact the overall strength and rigidity of the hull. Additionally, the type of metal used, such as extruded or sheet aluminium, can also affect the boat's performance and durability. It is important to note that a well-supported thinner hull may outperform a poorly designed thicker hull. Therefore, it is essential to evaluate the overall construction and design of the boat, not just the hull thickness in isolation.

When deciding between boats with different hull thicknesses, it is crucial to consider your specific needs and intended use. If you plan to use the boat primarily in calm waters or rivers, a lighter boat with a thinner hull may be a suitable option. However, if you anticipate venturing into rougher waters or prioritising durability and comfort, a heavier boat with a thicker hull may be a better choice. Additionally, it is worth considering the towing and fuel requirements for each option, as these can impact your overall boating experience and operational costs.

Aluminium alloy type

Aluminium alloys are widely used in the marine industry due to their unique properties. Aluminium is lightweight, strong, highly weldable, and resistant to corrosion, making it ideal for boat construction. The specific alloy chosen for a boat will depend on its intended application.

The Aluminium Association of the United States has developed a naming system for aluminium alloys, and there are over 500 registered designations. Of these, four are commonly used in the marine industry: 5052, 5083, 5086, and 6061. These alloys have typically been strain-hardened and stabilised, giving them a heat number of H3.

The 5000 series alloys, including 5052, 5083, and 5086, use magnesium as their principal alloying element, which makes them easier to weld. These alloys are generally used for interior parts of boats, such as cabins, decks, and gunwales. 5083 is stronger than 5052 and is widely used in marine environments where corrosion resistance is crucial. 5086 is considered superior for marine environments due to its increased corrosion resistance, especially in saltwater. Both 5083 and 5086 are commonly used for hull bottoms and side sheets.

The 6000 series alloys include 6061 and 6063, which are also marine-grade and well-suited to seawater. 6061 aluminium alloy is a general-purpose alloy used for structural components and can be used for exterior hull reinforcement. While it has more strength than the 5000 series alloys, it is not as easily formable and is more prone to fracturing. 6063, on the other hand, offers greater formability and features a high surface finish that is good for anodizing.

In addition to hull construction, aluminium alloys are also used for various parts and equipment on boats and ships, including windows, doors, ladders, railings, pipes, tubes, and outriggers. The specific alloy chosen for these applications will depend on the particular requirements of each component.

Boat length

When it comes to boat length, there are a few things to consider. Firstly, the intended use of the boat is important. If you plan to use the boat in shallow waters or rivers, a shorter boat may be more manoeuvrable and easier to handle. For example, a 12-foot aluminum fishing boat can be transported without a trailer and is ideal for very small or remote lakes or rivers. On the other hand, if you intend to take the boat out on bigger waters, a longer boat in the 21-23 foot range might be more suitable.

Another factor to consider is the boat's beam width and deadrise. The beam width refers to the width of the boat from the top of the gunwale on one side to the other. While a wider beam can provide more space and stability, it's important to consider whether it will be a hindrance when towing or storing the boat. The deadrise, or the steepness of the boat's V-shape, also affects the boat's performance in choppy waters. A deeper V will provide a smoother and drier ride, making it more comfortable for passengers.

Additionally, the length of the boat can impact its speed and fuel efficiency. A longer boat may require more horsepower and fuel to achieve the same speed as a shorter boat. However, a longer boat may also have more space for fuel tanks, which could extend its range.

It's also worth noting that the length of the boat can affect its price. Generally, the longer the boat, the higher the cost. This is because a larger boat will require more materials and labour to construct. Therefore, it's important to consider your budget when deciding on the length of the boat.

Lastly, when comparing boat lengths, it's important to look at the centerline length rather than just the overall length. The centerline length measures the distance from the bow to the transom, excluding any additional features like the pulpit or motor bracket. This provides a more accurate representation of the boat's actual length.

Frequently asked questions