Corrosion is among the greatest worries of any mariner. That's why a number of them rely on sacrificial anodes to counter this problem and de-risk their vessels. A sacrificial anode is nothing but disposable metal that can be attached to those parts of your boat that are continually submerged. These anodes are referred to as sacrificial; because they sacrifice themselves by corroding first so that your other vital metals are left unharmed.
These anodes function on a simple principle. When two dissimilar metals come in contact underwater, a naturally-occurring electricity transfer takes place between the two metals. When this happens, the metal that is more active will corrode first. So, when an anode is installed on your propeller or hull, it is the more active metal and thus it corrodes first. However, once the anodes have corroded to a certain extent, they cannot be used further and need to be replaced immediately. Typically an anode should be replaced when it reaches 40%-50% of its original size.
Such anodes are commonly made of zinc, but there are other metals such as magnesium and aluminum that are also popularly used. The best way to determine the suitability of an anode is to first check the type of water they will be used in. For instance zinc or aluminum anodes should be used in salt water and in brackish water too these two anodes can be used. However, it is important to note that the fresher the water, the lower will be the amount of electric current transfer. This means that you should use an aluminum anode that is more active. When it comes to fresh water applications, magnesium anodes are the best choice.
Should you have any doubts about the suitability of different anodes or line cutters for your marine applications, it is advisable to discuss your requirements with your local area dealer, boat manufacturer or certified marine electrician. While zinc and aluminum anodes have been widely used, magnesium anodes are also becoming increasingly popular these days. Lets take a look at what makes magnesium sacrificial anodes a preferred choice:
So before you make a final selection, it is advisable to take the professional opinion of a leading distributor of sacrificial anodes and line cutters.