The Passport Project: Part 13 (Bringing an old anchor chain back to life)

Aug 1 2012 in The Passport Project by Marty McOmber

I love anchor chain. Next to an anchor that sets hard and fast, knowing that our boat is connected to the bottom by a quality anchor chain is what lets me sleep soundly at night.

I knew that Meridian, like our previous boats, came with an all-chain anchor rode and that made me happy.

What made me not so happy when we bought the boat in April was the rust I could see on the first 30 feet of the chain. But a closer inspection by our surveyor suggested that this was mostly superficial and that the rest of the rode looked in good shape.

Still, it was clear that after more than 20 years, the chain needed some TLC.

 

The first 30 feet or so of anchor chain were looking a little too rusty for my tastes.

I looked into how much it would cost to replace all 300 feet of the 3/8-inch BBB chain. About the best price I could find was north of $1,500.  Ugh.

Fortunately, our friends and Northwest cruisers Aaron and Nicole Maraschky, the owners of  S/V Bella Star (now sailing in Costa Rica), had a great tip for us — rather than buy new chain, regalvanize it.

According to Wikipedia, galvanization is “the process of applying a protective zinc coating to steel or iron, in order to prevent rusting. The term is derived from the name of Italian scientist Luigi Galvani.”

Without galvanization, in other words, our anchor chain would rust away lickety split in a saltwater environment.

I am always amazed by Aaron’s ability to find the best deal when it comes to boat projects. And true to form, he found a local shop in Ballard that specialized in galvanization at a reasonable price: Scott Galvanizing.

While our boat was on the hard in Port Townsend, I drove my pickup truck under the bowsprit and dropped all 300 feet of chain into the bed.

I must have driven past Scott Galvanizing thousands of times and not given it much thought. The company has been in business more than 50 years, located just west of the Ballard Bridge on Leary Avenue.

The building isn’t much to look at, and it is definitely a throwback to the days when Ballard’s industrial core was humming. But it’s just the kind of place you want to go when you have a project that requires dipping a bunch of steel chain into a vat filled with molten zinc.

The folks at Scott were great. Within a few minutes, they pulled the chain out of the bed of the pickup, piled it onto a wooden pallet and whisked it away. They told me it would be ready to pick up the following week.

Bye-bye, old chain.

According to Scott’s website, the galvanization process is done in two main steps — preparing the steel, and then galvanizing it.

Preparation includes using a hot alkaline solution to clean dirt, rust, grease, paint and other materials from the chain. This is followed by pickling, which utilizes a diluted solution of sulfuric acid to remove any remaining rust and mill scaling. And finally, fluxing, which removes oxides and ensures that the steel is ready for its molten zinc bath by dipping it in a solution of zinc ammonium chloride.

And I thought acetone was nasty stuff.

The second main step is the actual galvanizing. In my case, the chain was dipped in a bath of molten zinc that is heated to nearly 850 degrees Fahrenheit, which sounds something like hell for a rubber duck.

In the bath, the zinc reacts with the iron in the steel to create layers of zinc-iron alloys topped by a layer of pure zinc. The chain is then removed from the vat and the excess zinc is drained off in a centrifuge.

Unfortunately, Scott Galvanizing doesn’t let customers like me watch the process. But a week later, I arrived with my pickup ready to see the results.

It was amazing. Have a look.

 

Hello new!

For about $300, I had what for all practical purposes is a new chain, ready for a few more decades of cruising in the Northwest and beyond.

And for those who wonder just how durable this galvanized coating is, apparently it holds up pretty well.

Aaron reports that after more than a year of constant use, dragged across rocks and rough bottoms from the West Coast of Vancouver Island to the sunny shores of Coast Rica, his chain still shows no sign of rusting or wear.

Now that’s what I call a bargain.

Avatar of Marty McOmber

About Marty McOmber


Marty McOmber is editor and co-founder of Three Sheets Northwest. He is an avid sailor and long-time professional journalist. You can find Marty aboard Meridian, a Passport 40.