Fasteners For Aluminum Jon Boats: Choosing The Right Ones

When it comes to fastening an aluminium jon boat, there are a few options to consider. Stainless steel is a common choice for fasteners, but it's important to note that not all stainless steel is created equal. Type 316 stainless steel is more corrosion-resistant than type 304, especially in saltwater environments. Another option is to use aluminium fasteners, which won't cause corrosion due to dissimilar metals but may not provide the same level of strength. To increase the strength of aluminium fasteners, consider using aluminium pop rivets with steel shafts, which offer greater durability than aluminium alone. Additionally, applying a coating of Tef-Gel or a similar product can help reduce the risk of corrosion and make it easier to unscrew fasteners in the future.

Stainless steel bolts are suitable for aluminium boats

When choosing stainless steel bolts for an aluminium boat, it is essential to select the right grade of stainless steel. While 304 stainless steel is commonly available, it is not ideal for marine applications. Instead, opt for 316 or 316L stainless steel, which are better suited for use in the marine environment. Additionally, consider the location of the bolts. If they will be below the waterline, it is advisable to use a sacrificial anode to help prevent corrosion.

Another factor to keep in mind is cost. Stainless steel hardware can be expensive, especially when purchased in small quantities. Buying in bulk can help reduce the overall cost. Finally, it is worth noting that some boat manufacturers originally used stainless steel bolts, so using the same type of fasteners for repairs or modifications can be a good option. However, it is always important to inspect the boat for any signs of corrosion and take appropriate preventive measures.

Use sacrificial anodes to prevent corrosion

Corrosion is a common issue for aluminium boats, especially in saltwater. A great way to prevent this is by using sacrificial anodes.

Sacrificial anodes are metal rods made from a material that corrodes more easily than the metal it is protecting. When connected to the boat, the anode attracts corrosion to itself, extending the lifespan of the boat. This process is known as galvanic corrosion and occurs when two metals with different electrical activities are immersed in the same liquid, such as seawater.

In the case of aluminium jon boats, sacrificial anodes made of zinc, aluminium, or magnesium can be installed. Zinc is the traditional choice and works well in saltwater, but it is heavy and toxic to the environment. Aluminium is lightweight and works in both saltwater and brackish waters, lasting up to 50% longer in saltwater than zinc. Magnesium is the best choice for freshwater but does not perform well in saltwater.

When choosing an anode, it is important to consider the type of water the boat will be used in. For saltwater, aluminium anodes are recommended as they are more active, provide better protection, and last longer than zinc. For brackish water, aluminium is also the best choice as it provides superior protection without suffering the fast corrosion rates of magnesium. For freshwater, magnesium is the clear choice as it offers superior protection.

It is important to replace anodes regularly, even if they still appear to be in good condition. Manufacturers recommend replacing anodes yearly as a precaution. To ensure proper functionality, anodes should be inspected for proper electrical continuity and good connectivity with the metal being protected. They should also be installed with new fasteners and never painted.

Sacrificial anodes are an effective way to prevent corrosion in aluminium jon boats. By selecting the appropriate anode material based on the type of water the boat will be used in, boat owners can extend the lifespan of their boat and protect their investment.

Avoid steel and galvanised bolts

When it comes to fasteners for your aluminium jon boat, it is important to avoid steel and galvanised bolts. While steel bolts are a common choice for many projects, they are not suitable for use with aluminium boats due to the risk of corrosion.

Steel is a highly reactive metal that can cause galvanic corrosion when used in direct contact with aluminium, especially in a marine environment. Galvanic corrosion occurs when two dissimilar metals are in contact and exposed to an electrolyte, such as saltwater. In this case, the steel bolts would act as the anode and corrode preferentially, while the aluminium boat would be protected. However, the corrosion products of steel can be very damaging to the aluminium, causing pitting and even holes over time.

Galvanised bolts are also not suitable for aluminium boats as the galvanisation process involves coating the steel with zinc, which is even more reactive than steel alone. While galvanisation can provide protection against rust in some applications, it is not effective when the galvanised steel is in direct contact with aluminium. The zinc coating will quickly corrode, leaving the underlying steel exposed, and the corrosion products can damage the aluminium just as steel bolts would.

To avoid these issues, it is best to choose alternative fasteners made from materials that are less reactive with aluminium. Stainless steel, for example, is often recommended for use with aluminium boats, although it is important to ensure that the correct grade of stainless steel is used to minimise the risk of galvanic corrosion. Other options include nylon, bronze, brass, copper, or even titanium fasteners, depending on the specific application and environment.

Additionally, it is important to consider the use of insulating materials, such as nylon washers, to separate aluminium and steel or galvanised components when complete avoidance of these materials is not possible. Proper sealing and protection of fasteners, such as with marine-grade adhesives or lubricants, can also help to mitigate the risks of corrosion.

Use aluminium, Monel or stainless steel blind rivets

Aluminium, Monel or stainless steel blind rivets are ideal for fastening an aluminium jon boat. They are strong, durable and will not corrode.

Aluminium rivets are a good choice if you want to avoid any potential corrosion issues. They are also easier to set than other types of rivets and can be found with non-rusting steel cores. If you are concerned about the strength of aluminium rivets, you can opt for stainless steel or Monel rivets, which offer greater strength and are suitable for use in marine environments.

Monel rivets are made from a nickel-copper alloy and are highly resistant to corrosion, even in saltwater. They are commonly used in marine applications and are known to be stronger than aluminium rivets.

Stainless steel rivets are another option for fastening your aluminium jon boat. They are strong and suitable for use in marine environments. However, keep in mind that stainless steel is more expensive than other types of rivets and may require a special rivet gun for installation.

When installing rivets, it is important to use a coating of sealant or insulating material, such as Tef-Gel, Duralac or 3M 5200, to prevent galvanic corrosion between the rivet and the aluminium boat. This is especially important if you are using stainless steel or Monel rivets.

Additionally, when working with stainless steel rivets, it is recommended to use a pneumatic rivet gun as it provides a tighter fit than a hand-operated popper.

Use sealant to prevent water from reaching and destroying core

When it comes to fasteners for an aluminium jon boat, the use of sealant is crucial to prevent water ingress and subsequent damage to the core. While fasteners such as stainless steel or aluminium bolts, screws, and rivets are essential for securing hardware and fittings, sealant acts as a critical barrier to prevent water intrusion.

Sealant plays a vital role in safeguarding your aluminium jon boat from water damage. By filling gaps and creating a watertight seal around fasteners, it prevents water from reaching the core of your boat. This is especially important as water can cause the core to deteriorate over time, compromising the structural integrity of your vessel.

When selecting a sealant, opt for one that is specifically designed for marine use and is compatible with aluminium. Some recommended options include 3M 5200, GOOP Marine, and Boatlife Life-Calk polysulfide. These sealants are known for their strong adhesion to aluminium and their ability to resist water penetration.

To ensure a proper seal, it is essential to follow the manufacturer's instructions for applying the sealant. This may involve cleaning and preparing the surface, applying the sealant generously, and allowing adequate curing time. Additionally, consider using butyl tape in conjunction with the sealant to further enhance the watertight seal, especially around fasteners.

By taking the time to select the appropriate sealant and applying it correctly, you can rest assured that your aluminium jon boat is well-protected from water intrusion. This simple yet crucial step will help maintain the integrity of your boat's core and ensure a safe and enjoyable boating experience.

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