One of the areas of a boat prone to the most wear and tear is the stainless steel. Stainless steel is subject to corrosion and pitting despite being marine grade when not properly cared for. For this reason it is critical to understand how to maintain marine grade stainless steel on a boat. I am a former captain who detailed vessels on a consistent basis and in particular stainless steel. Here is how to maintain marine grade steel aboard your watercraft. 

Where Is Stainless Steel Found On A Boat

Without question, stainless steel is prevalent aboard boats and is likely in places you don’t consider. 

The most notable stainless fitted on a boat are rails along the bow, the cleats, and hinges for deck hatches. 

However, don’t forget about the least notable places, such as small grab rails on the transom, water ski pylon if equipped, and railings around windshields and in particular, center console vessels. 

When maintaining stainless steel aboard a boat, it is critical to detail each and every piece to prevent long term damage. 

Why Is Marine Grade Stainless Steel Prone To Corrosion 

Let’s start by making it clear that there are two types of marine grade stainless. First is 304, which is less resistant to corrosion compared to 316 stainless steel. While both are manufactured with a chromium outer shell, 316 stainless also includes molybdenum. The combination of the two makes 316 far more resistant to corrosion in comparison. 

Without a doubt, corrosion is avoidable when following a proper maintenance routine. One of the primary culprits causing corrosion is saltwater. However, don’t assume your stainless won’t rust if you only operate in freshwater. An additional cause of corrosion is moisture. 

One of the most prominent signs of the start of corrosion is small yellow-brown spots called tea staining. However, staining and corrosion are preventable by removing salt accumulation, drying stainless after rainfall and condensation, and routinely waxing. 

How to Properly Clean Stainless Steel

Understanding how to properly clean marine grade stainless steel is essential to prevent the onset of corrosion. 

No matter if you’re operating in saltwater or freshwater, it is important to wash and dry the steel. However, it should be noted that extra time is required when using a vessel in saltwater environments. 

When it comes to cleaning and drying stainless steel, it is critical in any of the three following circumstances. 

Routine Cleaning

Without a doubt, marine grade stainless requires routine cleaning. Particles in the air accumulate on the metal leading to corrosion. Furthermore, this is most common when the vessel is stored in a dry rack or marine in coastal waters. Salty air coats the stainless despite the boat being stowed away. 

As a boat owner, it is essential to wash and dry the stainless even when the boat is not in use. Make it a habit to clean at least weekly despite the vessel being laid up on the trailer, at the dock, or on a dry rack. 

Cleaning After Boating

Again, when comparing saltwater operation versus freshwater, the technique and necessity for a thorough cleaning are not the same. 

Let’s start out with boats operating in freshwater. While salt does not accumulate, it is still important to rinse and occasionally wash stainless steel to remove contamination. Lastly, thoroughly dry after rinsing or cleaning. 

Saltwater boaters must be diligent when it comes to cleaning stainless. Every time the boat ventures out, the stainless steel must be thoroughly washed with soap and water. I have seen people make the mistake of failing to wash the underside. To test if salt was removed, slide your hand along the bottom of the stainless rails. Improper cleaning will result in a handful of salt. For this reason, I recommend using a wash mitt, as you can wrap your hand around the rails. 

Keep The Stainless Steel Dry

No matter if you washed the boat, if it rained, or if condensation has accumulated, you’ll want to dry the stainless whenever you’re present. I lived aboard yachts, so this was my routine each and every morning as a result of dew and after every rainfall. I get it, it’s not possible to dry your stainless with a chamois mop after every rainfall and each morning when you’re at work and the boats on a trailer or at the marina. My suggestion is to keep the stainless dry whenever possible to prevent corrosion. 

Cleaner Wax And Insulator Wax Are A Must

While washing and drying are needed to help prevent corrosion, you’ll need to take it a step farther. In addition to washing and drying is, applying cleaner wax and insulator wax. Here is the correct process to apply wax to your boat’s stainless steel. 

Metal Wax

I know the process when it comes to waxing stainless steel because I have literally waxed miles of rails. 

One of the best products on the market to remove the beginning of imperfections in stainless steel is Collinite Metal Wax. The cleaner wax when applied, removes staining as a result of standing water or salt. 

To apply, use a soft dry rag with a dime sized drop of cleaner wax. You’ll need to buff the rails and apply more wax as needed. Importantly, be sure to buff all sides of the stainless. After buffing, allow the cleaner wax to dry thoroughly. The wax is dry when it turns white and forms a chalky crust. 

Importantly, after the cleaner wax is removed, inspect the railings and determine if any persistent stains remain and repeat. 

Insulator Wax

Insulator wax is a top coat that performs the same function as applying wax to your car. The function is two fold. First, it adds an extra layer of protection by allowing water to bead up and roll off. Secondly, it prevents contaminants from making direct contact with the stainless. 

In regards to the process of applying insulator wax, it is the same in comparison to cleaner wax. Again, use a soft clean rag and apply a dime size drop of Collinite Insulator wax. Apply the wax to all areas of the stain. Allow the wax to dry, and remove with a clean, dry rag. 

It should be noted that the application of insulator wax must be part of your routine maintenance. I recommend applying wax to stainless on a monthly basis to prevent corrosion. 

Maintaining Boat Stainless Steel Is Essential

In order to keep your boat in tip top shape with a bright shine, you’ll need to give your marine grade stainless steel attention. With that being said, remember to wash and dry the stainless as often as possible. Additionally, if you’re not already, wax the stainless steel on one month intervals. The combination of the two should keep your stainless steel free of corrosion.