Anodes, anchors and sex

Fri 20 Oct 2023 13:11

Anchoring is touchy for lots of yotties. ONLY this or that type of anchor will do. 

Whatever the choice, we can agree that anchors are blinking expensive to replace. Like nearly a grand for a big one, ouch.  They need replacing when they start going rusty. Same with anchor chains. 

Contrary to some muppet on YouTube, anchor chains don’t lose their zinc coating due to being jiggled about on the sea bed. Otherwise they wouldn’t go rusty all over and even inside the links, would they? They’d just be rusty on the outside.  

Anchors and anchor chains go rusty on cruising boats cos they’re in the (often v warm) seawater for  MONTHS every year. Whereas the thin zinc coating assumes they’ll be used just a few nights out every season. The electrolysis sizzles anything metal, starting with magnesium, then zinc, aluminium then cast iron etc. 

So with this in mind I have lashed a load of extra zinc anodes to the anchor. 

Unlike most metal stuff on boats, anodes can be a bit of a lashup.  Like mine are. They’re sacrificial, obviously- they get eaten by the galvanic electrolysis before the important steel bit of anchor. Attaching them to the anchor with hose clips is fine. 

Now, another way to reduce the galvanic action on the anchor and chain COULD be to isolate the chain from the rest of the boat. Say, by using rope as the last bit holding the boat to the chain.  You’d still need anodes but maybe not so much.  I might have go at this in the coming season. 

Meanwhile here’s the stupid-looking anchor.  Aesthetically ugly but galvanically beautiful. 

On a final note, Luigi Galvani is the historical figure who is credited with saving lots of ships in the Age of Exploration with the discovery that iron fasteners were at great risk and the failure of these may have contributed to numerous castastrophic hull failures.  Another factor was that any metal (including ship nails etc) was highly prized by distant natives, and hence the alternative meaning of the word “screw” ahem. Yes, the crew would enterprisingly and secretively dismantle the ship to exchange the metal holding it together in exchange for sex.