Compared to full carbon hydrofoils, aluminum hydrofoils have the undeniable advantage of a much cheaper price. On the other hand, they also have some negative aspects that it is good to know BEFORE buying, to avoid nasty surprises. Beyond the aspects related to performance, which in our opinion a beginner can easily overlook, there is an aspect that concerns the maintenance of aluminum hydrofoils that anyone who buys one should know, an aspect that is not always sufficiently explained to those who buy. a new foil.
Electrolytic-galvanic corrosion is an electrochemical corrosion phenomenon linked to the contact of 2 different metals placed in contact with each other. The corrosive process is linked to the movement of electrical charges by means of ions and requires three main elements, two electrodes (Metal 1 and Metal 2) and an electrolyte.
The different electric potential of two different metals, such as the aluminum of your column and the steel of the screws, whose potential difference is very high.
When a galvanic current occurs, the less noble metal corrodes in the presence of moisture, salts or water, generating the galvanic currents which are electric currents of low intensity. This causes oxidation near the contact part between the two metals.
All this occurs, as the nobler metal attracts the electrons of the less noble one, thus initiating electrolytic corrosion, an irreversible process capable of damaging the outer surface of the material.
How to prevent galvanic corrosion
To prevent galvanic corrosion, it is best to isolate metals with different potentials and create an environment without any type of humidity around them. This can be done by sprinkling the parts at risk of galvanic and therefore in particular the screws and all the points of contact between the aluminum column and the screws or steel plates.
Some of the newer aluminum foil models already have coatings in the factory to avoid these drawbacks. Otherwise or for greater safety, it is good to pass a specific product.
There are various products that can work well for this purpose, but the most used and that works very well is Tikal Tef-Gel.
It is a specific grease for use in the marine environment, which applied as an insulator between the two different metals, effectively preserves galvanic corrosion to the detriment of aluminum, a phenomenon that in the long run weakens the structures and makes them dangerously vulnerable. It will have to be used at each exit, or at least when none remains from the previous application.
Maintenance of the aluminum hydrofoil
To avoid unpleasant surprises, such as locking screws or corrosion of your beloved hydrofoil, it is essential to completely disassemble the foil after each ride. In reality, even if you have not gone out but brought the foil to the beach and assembled it, it is important to reassemble it immediately afterwards.
After having completely disassembled it, you must rinse and dry each part and, finally, apply the specific galvanic anti-corrosion grease on the joints and mounting screws.