dosjers wrote:
zinc anodes will do nothing to protect them from corrosion... unless the zinc is submerged in an electrolyte (water)
Disagree.
First, note that Aluminium will corrode aerobically (ie, in air), but quickly forms an aluminium oxide layer that actually protects it to a good degree from further corrosion. Doesn't stop it entirely, but slows it a big heap. "Unlike steel, when aluminium corrodes the resulting layer of oxidation is air-tight and rock hard, keeping the material underneath very highly protected. Even scrapes and scratches will form their own protective coat over time."
Galvanic corrosion, which is a way bigger problem however, does
not require "continual immersion". In our yaks, we have periodic immersion... well, they periodically get wetted by salt water anyway... but then we store them. That salt water "dries"... or does it? Actually salt is strongly hygroscopic, so it absorbs water from the atmosphere.
This absorption of water by the 'dried' salt provides a concentrated electrolyte, which enhances the galvanic reaction... kinda like adding an overly-strong acid to your car battery. Decades ago, I lived in a flat close to the ocean for a while, and saw mega corrosion of aluminium framed windows, which had been installed with steel screws. Over the last decade, I've done a lot of camping, mostly ocean-front. Any aluminium in contact with steel (such as screws etc) was rapidly destroyed.
Ideally, we should all thoroughly wash down our yaks with fresh water - and
every piece of gear we use - after
every salt water outing. But even if we actually did do that, we still wouldn't get rid of all the salt in every nook and cranny.
To protect our investment, it would be cool if Hobie would offer a custom zinc sacrificial anode - maybe something that could simply slip inside the aka cross braces.
In the meantime, I'll be looking for a suitable zinc anode to fit inside a x-bar myself!