Electrochemical damage to wooden boats. It's a thing

[Russian007]

Both wooden boats I've owned have suffered from this onerous and seldom discussed form of wood decay-- the socalled and dreaded delignification of wood. Electricity disrupts the cellular structure of wood and turns your major structural members into shredded wheat cereal. Sailors caught in doldrums have been know to subsist off deliginified planks. Okay that's a lie, but it is a problem. The whole topic is heady and I've always thought this article is the best summation. Thought I'd subject it to some stress testing here and see if the explanations and suggested remedies are still credible. https://waitematawoodys.com/2015/05/...f-leaky-homes/

[Benz]

Best remedy is a fiberglass boat.

[Russian007]

Originally Posted by Benz

Best remedy is a fiberglass boat.

except glass boats typically have wood stringers and could be subject to same phenomena.

[Sailmonkey]

Originally Posted by Russian007

except glass boats typically have wood stringers and could be subject to same phenomena.

Highly unlikely as the wood in a glass boat is intended to stay dry and encapsulated in plastic.

[Benz]

Originally Posted by Russian007

except glass boats typically have wood stringers and could be subject to same phenomena.

Sorry; should have said "a well-built glass boat." Encapsulating wood is always a bad idea in my book.

[AKA-None]

Originally Posted by Benz

Sorry; should have said "a well-built glass boat." Encapsulating wood is always a bad idea in my book.

So no balsa cored decks?

[Benz]

Originally Posted by AKA-None

So no balsa cored decks?

Absolutely not. I know that was common once, and many are still successfully dry, but none of the boatbuilders I know around here, even the cheapest chopper-gun, polyester spraying boat shop will put balsa in a boat.
Balsa is great for molds, and for structures in a dry environment, but not in the structure of a boat. The odds of water intrusion, early or late, are too great.

[EngineerRetired]

As always, salt water is the culprit. Without it the electrical current would not flow through the wood. Believe it or not people deliberately use this phenomenon to create "art". If you have never seen it do a YouTube search for Lichtenberg Device. Yes they use higher voltages to speed the process up but its the same principle at work.



Solution? Same as always, keep the salt water on the outside of the boat.

[roverhi]

the problem with metal and wood has been known for centuries. It was known as Iron Sickness to the Royal Navy. When they began to use iron/steel to replace wood pins and rudder fittings that electrolysis quickly came to light. No problems with copper sheathing to repel worms and other growth. Paul Revere developed a process to make sheet copper for sheathing ship bottoms.

Bronze doesn't seem to cause much of an issue and probably stainless steel. Salt is a wood preservative, it's the creatures that live in salt water it that cause the problems. Boats sailed in fresh water or areas subject to rainwater often spread salt around mast bases etc to preserve the wood.

[luckylinda]

Since when is polyester impermeable to water?

[stinkpots]

Originally Posted by Russian007

Both wooden boats I've owned have suffered from this onerous and seldom discussed form of wood decay-- the socalled and dreaded delignification of wood. Electricity disrupts the cellular structure of wood and turns your major structural members into shredded wheat cereal. Sailors caught in doldrums have been know to subsist off deliginified planks. Okay that's a lie, but it is a problem. The whole topic is heady and I've always thought this article is the best summation. Thought I'd subject it to some stress testing here and see if the explanations and suggested remedies are still credible. https://waitematawoodys.com/2015/05/...f-leaky-homes/

Thank you for posting this.
I own a 51 foot Kauri motor yacht that was built to Lloyd's 100a1 in 1972. When I bought her 7 years ago there was a small amount of degradation around one bronze thru hull. I replaced all thru hulls with high grade strengthened plastic ones. I removed a copper ground plate from the hull.
I am only part way through the battle however. I have just found my bronze transducer is degrading the planking around the fitting. I have continued the original practice of having an anode on my bronze rudder fittings, I will remove this now. My remaining problem are the 2.5 inch stainless shafts.
Thanks again for raising this issue and the excellent article, I will double down on my efforts. Thankfully my boat was very well built and is still in excellent condition 50 years on. I just have to make sure she has another 50 in her.

[Sailmonkey]

Originally Posted by luckylinda

Since when is polyester impermeable to water?

In the quantities it matters to wood succumbing to electrical currents, polyester is good enough

[kish]

Originally Posted by Benz

Sorry; should have said "a well-built glass boat." Encapsulating wood is always a bad idea in my book.

100% correct.
Encapsulating wood in epoxy is a "remedy" that will give you a ten year remission from an underlying problem, if carefully done in a controlled atmosphere.
Wood is a natural product and if allowed to breath and dry out after becoming wet, will not suffer from rot.

Epoxy sealed wood, flexing in a seaway will develop hairline cracks, which allows water ingress and the rot starts from within! dry rot

As done by most non specialist folk in a hurry, epoxy treatment will give a 3 to 5 year cosmetic repair, ideally done prior to boat sale.

[Simi 60]

Originally Posted by kish

100% correct.
Encapsulating wood in epoxy is a "remedy" that will give you a ten year remission from an underlying problem, if carefully done in a controlled atmosphere.
Wood is a natural product and if allowed to breath and dry out after becoming wet, will not suffer from rot.

Epoxy sealed wood, flexing in a seaway will develop hairline cracks, which allows water ingress and the rot starts from within! dry rot

As done by most non specialist folk in a hurry, epoxy treatment will give a 3 to 5 year cosmetic repair, ideally done prior to boat sale.

I wonder how all those timber cored strip plank epoxy boats and duflex (balsa epoxy) boats survive so long

[Fore and Aft]

I wonder as well Simi 60. I surveyed a 20 year strip plank cedar catamaran yesterday that had been encapsulated with epoxy/fiberglass cloth and she was still as good as the day she was launched.
Russian007 your right about the timber degradation. I surveyed a 40 foot timber bay cruiser and everyone of the sea cocks were joined by a grounding wire? Consequently every seacock had severe soft timber issues around them.
Cheers