11th Mar 2020
The purpose of a boat anode is to protect underwater metals from galvanic corrosion that occurs when two dissimilar metals are immersed in a conductive solution and are electrically connected. The most common area of use for narrow boat anodes is the hull.
What Are Narrowboat Anodes?
As mentioned previously, anodes are designed to protect underwater metals from corrosion, so should be attached to underwater areas of the narrowboat, such as the hull.
Three main metals are used for anodes, they are:
Aluminium Anodes:
Suitable for salt and brackish water use, aluminium anodes are the most cost-effective choice of anode. Aluminium anodes are cheaper than zinc anodes, have a longer lifespan and weigh less, improving fuel economy.
Magnesium Anodes:
Magnesium is the only metal of the three that works well in fresh water where there is a lower open circuit potential. Aluminium anodes can be infrequently used in fresh water, but do not offer anywhere near the protection in comparison with magnesium anodes.
Zinc Anodes:
The traditional metal of choice, zinc anodes are suitable for use if your narrowboat is in salt water. Compared to aluminium, zinc anodes do not provide the same level of protection, nor do they last as long.
How many anodes do I need?
Working out how many anodes you need can often be quite a complex and confusing question as there is a fine line between under protecting and over protecting. Too much protection can lead to paint blistering, with too little leading to corrosion.
Ultimately, there is no definitive answer to this question as it depends on a wide range of factors, with the main one being the size of your hull.
In this case we’d recommend getting in touch with our highly experienced crew – we can then give you tailored advice on how many anodes you require, their size and also where to place them. Our team has decades of experience, so you’re in the right hands.
Conclusion:
As you may be able to guess from the information above, and from various other blog posts, anodes (at times) can be a complex and rather confusing part of the boat maintenance cycle, which is where we’re here to help.
If you have any questions about anodes, we’d love to assist. Call us on 01634 295 233 or email us (customerservices@piratescave.co.uk) and one of our highly experienced crew members will be happy to assist.
