Skip to main content

Hot Stick

Jim Liggett of Cornish, New Hampshire, asks:"I am installing a lightning- ground system and plan to use a 5/8in rod extending at least 6in above my VHF antenna. Does it matter whether the pointed rod is solid copper or can it be copper-coated steel, as is often used for grounding rods on shore? If the steel rod will work equally well, is there a good way to keep the tip

Jim Liggett of Cornish, New Hampshire, asks:

"I am installing a lightning- ground system and plan to use a 5/8in rod extending at least 6in above my VHF antenna. Does it matter whether the pointed rod is solid copper or can it be copper-coated steel, as is often used for grounding rods on shore? If the steel rod will work equally well, is there a good way to keep the tip and the attachment point at the mast from corroding? Can you recommend a spray or galvanizing product?"

Tim Bartlett replies:

As an air terminal, a copper-coated rod should work perfectly well. Although steel is about ten times less conductive than copper, the rod makes up for it by having 10 times more cross-sectional area than the 4 AWG copper that is usually recommended as the minimum for the main conductor in a lightning protection system.

My bigger concern is that a copper-coated steel lightning rod installed on an aluminum mast might create quite a galvanic cocktail of different metals, and in a place where you are least able to keep an eye on what is happening.

The copper doesn’t need protection against corrosion. Rather it is the aluminum that’s at risk. Adding a bit of zinc-rich paint to the mixture could give some added protection, but I don’t expect it will make that much difference. My preferred solution would be to install an aluminum air terminal. It’s not that much more expensive, it’s only marginally less conductive than a copper unit, but it is much better than steel. Best of all, it poses no galvanic threat to your aluminum mast.

Related

Background-02

Notice to Mariners: A Blog from the SAIL Editors

As a teenager, I stumbled across a copy of Derek Lundy’s Godforsaken Sea in the back room of a used bookshop. I had never heard of the Vendée Globe and frankly found all the boat-speak in the first 50 pages a little difficult to get through. But Lundy’s storytelling and the draw ...read more

Screen-Shot-2022-01-13-at-9.26.59-AM2048x

VIDEO: Celestial Navigation Episode 2

Celestial navigation is an invaluable tool for all kinds of sailors. In episode two of the celestial navigation series, learn the basic elements of navigation and the sight reduction process using declination and GHA to determine the Geographic Position and navigate using a ...read more

Film-poster

Cruising: Year of the Sea Shanty

Along with other timeless pursuits, like baking sourdough and gardening, singing sea shanties surged back into popularity during the recent lockdown, thanks, in part, to the app TikTok and its “duet” feature, which allows singers from around the world create music together. By ...read more

Book-Cover-9780712353700

Book Review: Sailor Song

Sailor Song is the ultimate guide to the music of working sailors during the 18th and 19th centuries. The book includes lyrics and sheet music for 50 of the most beloved sea songs with fascinating historical background on the adjoining page. Chapter introductions provide ...read more

Screen Shot 2022-01-12 at 10.42.33 AM

Race Update: RORC Transat

With the fleet leaders about halfway to Grenada, the 2022 RORC Transatlantic is shaking out to be a tactically interesting one. The race, now in its 8th edition, began on Saturday with 30 teams ranging from 70-foot catamarans to a 28-foot JPK 1010. Early in the race, light winds ...read more

01-LEAD-IMG_1585

Experience: Fire Down Below

Due to the Covid-19 pandemic, local racing had resumed with household crews only. My wife, though, while always up for a pleasure sail, was not up for this kind of thing, so, for the fifth time in what was any measure an unusual sailing season, I found myself singlehanding my ...read more

BestBoats2022-logo

Best Boats 2022

In case you hadn’t heard, the fall 2021 boat show season was one for the record books. If there was ever any doubt the sailing public still enjoys making its way to Newport, Rhode Island, or Annapolis, Maryland, to see the latest in boat design, those doubts were put to rest ...read more

01-LEAD-Dominique-David-2048x

Mulithull Show Coming to La Grande-Motte

After a year without boat shows, 2021 proved to be a blockbuster summer and fall for events around the globe, and the International Mulithull Show is looking to continue that trend in 2022. First held in 2010, the show, which takes place in La Grand-Motte, France, on the shores ...read more