How to remove rust stains from fiberglass boat

A fiberglass boat is considered as a good investment since it can last for decades. Most of the mechanical and electrical systems will falter long before the fiberglass starts to show signs of wear and tear. 

Fiberglass is a great material since it is affordable yet strong and lightweight, making it the ideal choice for boats. Sadly, a disadvantage with fiberglass is that stains are likely to occur and the main culprit is no other than rust. Take note that the rust is typically seen at the base of all deck-mounted hardware. Read below to learn about boat stains and methods on how to remove rust stains from fiberglass boat. 

What causes rust stains on boats?

Rust stains are expected on boats due to the presence of stainless steel hardware. Remember that stainless steel has high corrosion properties. 

The marine-grade stainless steel includes a high nickel content, making it highly resistant to corrosion. There are various areas in a boat where fasteners and other steel components are exposed to water for extended periods which will allow corrosion to occur. Over time, the rust will start to stain the fiberglass. 

Rust stains on a fiberglass boat might also stem from galvanic corrosion. If steel is utilized with another metal in the presence of an electrolyte, there is a high chance for galvanic corrosion to occur. 

It is vital to keep different metals from touching each other. If this cannot be avoided, ensure that the two metals will not come in direct contact with one another by using a rubber gasket. 

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Steps on how to remove rust stains from fiberglass boat

If you want to get rid of the undesirable rust stains on your fiberglass boat, let us now take a look at the steps on how to remove rust stains from fiberglass boat.

  • Remove the hardware from the deck. Rust stains are likely to form wherever hardware are affixed to the deck. The best way to clean these areas is to remove all the fixtures as well as replace any corroded fasteners. 
  • Prepare the boat deck. After removing all the hardware from the deck, start the preparations for cleaning. Rust stains are considered as mineral stains. Simply wash the deck with soap and water first. Avoid using strong solvents such as acetone or an abrasive brush. 
  • Cleaning the rust stains. As mineral stains, you need a special type of cleaning agent that contains acid and a chelating agent to effectively deal with rust. These rust removers work in 2 steps – the acid dissolves the rust and the chelating agent holds the rust in suspension until it is washed away. Due to the chemical reaction, there is no need to brush the site. Simply wipe off and wash away any leftover. If traces of the rust stains linger, you need to rinse and repeat the process.
  • Rinse the deck thoroughly. After dealing with the rust stains, it is time to thoroughly wash the deck to get rid of any leftover cleaning agent. The next move is to apply some wax to protect the deck and make the removal of future stains easier. 
  • Polishing the fiberglass deck. If the gel coat appears dull, you can buff the surface. Use a power buffer, specifically the orbital sander.
  • Reinstall the deck hardware. Reinstall all the hardware that was removed. Before reattaching the hardware, apply some bedding compound to where the fasteners pass through as well as the entire base of the hardware. The purpose of this is to prevent moisture ingress in the future as well as lessen the accumulation of rust.
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How do you remove leaf stains from a fiberglass boat?

Leaf stains have been an issue of concern that boat owners face. It is important to note that tree leaves hold oils from the tree and every species leaves behind a distinct type of stain. Generally, tree oils are hard to remove and every so often leak into permeable materials. These oils are quite penetrating and can embed the stain deep into the gel coat. 

You can try out a variety of solutions, starting with a mild variety and switching to the stronger ones until the tree stains are removed. Some of the recommended cleaning agents are Boat Clean Plus or Boat Scrub. Although these options are the mild variants, they work effectively in getting rid of leaf stains. Simply dab on the stains and rub the site. If the stain lingers, allow the sun to bleach it after cleaning to remove the rest. 

For a stronger option that you can use on stubborn leaf stains, you can use Waterline Stain Remover. Simply apply on the stain and leave in place for 30 minutes and rinse thoroughly. Once all the stains are removed, do not forget to protect the deck with a protectant that seals all the pores as well as providing a protective coating to prevent future staining.

Is vinegar safe for fiberglass?

A fiberglass material is a synthetic form of fiber comprised of a plastic resin formed along with glass fibers. Various items in your house and workplace are made from fiberglass including showers, sinks, bathtubs, lighting fixtures, and even boats. There are various ways to keep fiberglass clean and free from stains. 

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If you want a safe and natural approach in cleaning fiberglass, vinegar can be used. Simply prepare a solution with water and vinegar. This cleaning solution can effectively deal with stains and water spots on fiberglass. 

Can you pressure wash a fiberglass boat?

If you have a fiberglass boat, it entails a lot of work despite having a lot of fun with it. The best way to make boat maintenance an easier task is to have a pressure washer. Let us take a look at the steps on pressure washing your boat. 

  • Use a biodegradable cleaning agent. Avoid ammonia-based solutions since these can both damage your boat and washer. 
  • Affix the pressure washer soap nozzle and shower the boat starting from the base and upwards to prevent streaking. 
  • Allow the cleaning agent to sit in place for up to 5 minutes while keeping the surface wet. 
  • If there are stains and buildup of algae or mildew, you can use the rotating scrub brush attachment. 
  • Rinse starting from the top and downwards. Use a 25-degree nozzle and wash away the detergent by drawing the pressure gun trigger and hold for a few seconds. Rinse the boat from the top and down. 

For extra protection, you can apply a marine wax after. 

Final thoughts

When it comes to unsightly stains on your boat, there are effective cleaning methods that you can try. Boats require regular maintenance to preserve its overall appearance. With the techniques on how to remove rust stains from fiberglass boat as well as other stains, your boat will look fresh and properly maintained. 

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