Looking After Your Stainless Steel - Fabrication

Bright and shiny stainless steel fixtures on all boats can really make a vessel stand out - especially when maintained properly. Learn how to clean, prevent and maintain your stainless steel.

A little stainless steel history lesson 

Stainless steel was discovered in 1913, English metallurgist Harry Brearley was seeking a way to improve the performance of rifle barrels. He found that by adding chromium to low-carbon steel, the alloy became resistant to rust.

Marine-grade stainless steel that we use today is a combination of metals that contains more than 10% chromium. All four elements chromium, molybdenum, nickel, and nitrogen work together to make stainless steel the metal of choice in harsh marine environments, especially saltwater. Stainless steel resists corrosion, called pitting, maintains its strength at high temperatures, looks good, and is easily maintained. 

However, while stainless steel is corrosion-resistant, it is not corrosion-proof. When exposed to harsh air and moist conditions, stainless steel can corrode or rust, which creates iron oxide. The chromium in stainless steel inhibits this process by producing its own oxide called chromium oxide, which resists further oxidation.

If left untended for a long, stainless steel will corrode away, more likely on components that are out of sight, like fastenings for deck hardware for example; water seeping under deteriorated bedding attacks the oxygen-starved stainless and eventually something gives. So, whenever you see tarnish stains on fastenings, investigate further. 

Types of Corrosion That May Affect The Stainless Steel on Your Boat

1. Atmospheric: Occurs when stainless steel is exposed to airborne liquids, solids, or gases, such as sea spray, rain, salt, or dirt.

Pro tip: The best way to prevent this type of corrosion is to wash your boat after every use, make sure to use lots of water and don't miss any spots.

2. Chemical: Occurs when the steel comes in direct contact with high chloride or corrosive materials, like bleach.

Pro tip: If you don’t rinse your boat really well after cleaning, you can end up with chemical corrosion. Bleach is a great cleaner, especially for fabrics and cushions, but it also corrodes stainless. Minimise where you use it and make sure to rinse it with extra water.

3. Contact: Occurs when small pieces of carbon steel, scale, copper, or other foreign material become lodged in stainless steel, causing pitting. This problem is caused by poor workmanship or wear when another type of metal comes into contact with your stainless steel hardware. You’ll see contact corrosion if you use a galvanised screw instead of a stainless one or attach a new brass or copper device to your stainless steel railing. 

Pro tip: If you can’t avoid using dissimilar metals, place a plastic or rubber insulator between them to prevent corrosion.

Tips For Caring For Your Boats Stainless Steel

Stainless steel is a relatively low-maintenance metal, but that doesn’t mean it’s without its pitfalls. This metal is prone to stains and other problems if you don’t clean it effectively. Follow our tips below to keeping your stainless steel protected and clean.

  • Regular cleaning and making immediate repairs to damaged stainless steel safety equipment are critical.
  • Marine-grade stainless steel fixtures are vastly different from chrome-plated equipmentStainless steel is non-magnetic; applying a magnet to onboard metals will help you determine the type of material you are cleaning. 
  • After each saltwater voyage, regardless of the length, a thorough hosing of the deck and all stainless steel fittings will dramatically reduce the potential for corrosion. Some elbow grease is required.
  • To clean stainless steel fixtures, use a soft cloth or a non-abrasive sponge together with fresh water and a mild marine grade cleaner (non streaking formula). The same material may also remove pitting. 
  • Using a second dry clean soft cloth, apply a polish by rubbing it onto the surface and letting it dry to a haze for 1-2 minutes then hand polish it to a high gloss shine. Repeating when necessary. A polish coating applied regularly adds protection and shine. Mount Marine Fabrication chooses to use Autosol.
  • Clean it often. You don’t have to give your stainless steel a deep, thorough cleaning every week, but you should include it as part of your regular routine just to preserve its fresh look throughout its lifetime.
  • Do not use steel wire brushes, sandpaper, or steel wool. Cleaning products containing chlorides or acids, especially bleach, should not be used.

Electrolysis & Tips to Prevent it

The electrolysis phenomena is an electro-chemical process that occurs when two different metals come into contact with each other in a saltwater environment.

Cathodic protection is the most common technique used to prevent corrosion on dissimilar metals. In its simplest form, the technique involves attaching a sacrificial anode (a material with a more negative electrode potential, like zinc, aluminum, or magnesium), which takes the impact of the electrical charge.

Boat manufacturers go to great lengths to design and build vessels that minimise the use of dissimilar metals that are in contact with each other, but there are areas on a boat where the contact is unavoidable, like lower units. Please see our tips below for keeping track and minimising electrolysis on your boat.

  • Know the areas where different metals are in contact
  • Take steps to ensure that cathodic protection material is in good shape
  • Replace or repair when needed

What can I do if my boat has signs of rust?

If the rust has pitted and is more than surface rust, this may require welding followed by pre-passivation process with an acid solution. Once completed, this will need to be finished with a marine grade polish. Mount Marine Fabrication provides a full stainless steel rust removal service. To enquire about this service use the following link click here.

With our helpful tips, you should have no problem with keeping your stainless steel as pristine as possible. If you would like to speak to us about your own stainless steel please don't hesitate to call today. 




Our team shines when it comes to creating custom marine Stainless Steel fabrication working with all types of marine vessels. Let us take your ideas and turn them into reality with ease. Take a look at some of our services below.

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