Epoxy bottom coating on wood boats...

[Cosmic Consciousness]

As I've been looking at various wooden classic motoryachts on the market, I have on numerous occasions come across boats where epoxy has been applied below the waterline to completely seal the hull. Considering epoxy is waterproof AND it has been applied after the hull has been saturated, isn't this inviting dry rot? If a wet piece of wood is sealed, fungus will work its magic and turn it into mush. I guess the question I'm asking is if I end up with an epoxy coated hull, am I inheriting a ticking timebomb?

[McSkagit Tim Jones]

Epoxy Barrier Coat on Wood Boats

I'm not a wood boat expert, but have been around boats long enough to know a few things about them. My brother was a wood boat purist. For him, it had to be Port Orford cedar planking on white steamed oak frames fastened with Everdur (silicon bronze).

If a wood planked boat has been in salt water, the salt tends to pickle the wood. It is possible to get electrolysis going in the wood which can attack the fastenings. One of the charter boat captains here had to have his wood 40 foot cutter refastened after electroysis was discovered in the bronze planking screws. Cost was $14K!

Most of the rot issues in epoxy clad boats comes from above (rainwater). If you have a really pristine wood boat you either have to keep it under cover or wash it down after every rain storm with sea water. I see the owner and crew of the 70 foot schooner Dirigo II moored near me out with their buckets on lanyards washing down the decks with sea water after every rain.

Then there is the expansion of wood in moist environments that has to taken into consideration on every hatch, door or just about any and every part of the boat. I learned this after launching the Saratogan when the cabin floor hatches suddenly couldn't be opened.

Keeping a wood boat outdoors or moored in the water is like trying to keep a grand piano outdoors. If you have lots of time, money and energy, it can be done. Modern cold molded wood boats eliminate many of these wood boat issues. Cold molded hulls are typically glued up with epoxy and then skinned with Dynel cloth saturated with epoxy. The Dynel/epoxy skin adds impact resistance to the wood.

My two cents worth.

Tim

[ChuckB]

Cosmic:
A couple of things; "Dry Rot" is a misnomer. Common term, most noted when rottren wood is found when it is dry, but water had to be there first. Wood kept dry will not rot, it will shrink, but not rot. All fungi require water to live and do their work, not necessarily much, but they need water. The intent of the epoxy on the outside is to keep water out, reducing the effects of fresh water on the hull and salt on the screws, may even help keep the Toredo worms out.
Other than that, follow Tim's advice. Salted wood is preserved against most fiendish fungal organisms.
ChuckB

[Tim_Mattson]

Cosmic,
I bet these are all moored hulls ,Epoxy is a petty much Universal primer and also called a "Barrier Coat".
Bottom paint would need this to stick well and withstand washing and such down the road.
Once applied ,bottom coats needs maintence and re-coating depending on type.Newer Bottom paints are getting more user friendly so it may not need the prep as it once did.
The better yards would put West Sytem clear Epoxy on before the multiple layers of basic 2 part primers,or at least I would hope......
Salty wood is really pickled well and the fasteners and drive gear are what go away in that Brine.
Wood does have a different way of riding in water as energy is absorbed more than Fiberglass or Alum hulls.
Hopefully Marty will chide in with an expert`s advice.
Keep shopping until then.......
TM

[Cosmic Consciousness]

Thanks for the valuable information, everyone! Happy New Year!

Some of the items mentioned in these posts shows how little I know about wood hulls...and how much more I need to learn. I did not realize to what extent fresh water damages wood. This, of course, brings about a few more questions.

I've mostly been looking at boats in the California Delta, which is mostly freshwater with some parts of it (near Antioch and Pittsburgh) being brackish. Thankfully, these boats have been stored in covered slips and have been relatively well maintained. The winter weather here is mild, so the extent of rain being blown into the covered boathouses is minimized...although we've had our fair share of horizontal rain over the past two years. On the other hand, summers are hot and, with relative humidity rarely exceeding 20 percent.

With that said, would I find boats here being more vulnerable to rot given the hull is not immersed in salt water? Also, if surfaces are covered and well protected with either paint or varnish and the wood is accordingly sealed and presumably internally dry, does fresh water still pose a threat?

Regarding electrolysis from the fasteners... I realize the old fasteners were mostly untreated bronze. With the newer fasteners being coated with silicon, is the coating itself an adequate isolator, or is it only marginally better than untreated bronze? I realize the bottom paint (or epoxy) is the best protection against fastener electrolysis...but the bottom paints also have high copper content to give them antifouling properties. The bottom paint I used on my Bayliner recently had something in the range of 30-40 percent copper. Needless to say, the paint is far far far from being dielectric. What types of impact would antifouling paints have on the fasteners?

Can anyone recommend a decent book or website to give further insight into these issues? I have taken a look at various books covering wood hulls, and most of the information was in reference to construction and fabrication techniques.

Thanks again for the insight. It just goes to show how much learning I have ahead of me.

Blue skies,
Ed

[McSkagit Tim Jones]

Fastenings for wood boats- Copper bottom coatings

Silicon bronze is one of many alloys of copper. Specifically, it is 95% copper, 4% silicon, 1% manganese. It has similar strength to mild steel, but is considered very corrosion resistant.

Corrosion issues in silicon bronze fastened plank-on-frame hulls is probably fairly rare and the cause is likely to be stray current from a leaking shore power connection either on the subject vessel or one moored close (a marina issue)

It's not the fresh water that is a problem, but all the little critters that live in it. A boat that is moored in fresh water under cover shouldn't have rot issues if the boat is maintained to any degree. Nonetheless, it would be a good idea to hire a marine surveyor with wood boat experience if you were serious about purchasing an older wood boat of any size.

The electrical conductivity of copper bottom paints is an interesting issue and I would like to know more about it. Like the fastener issue, I believe that most electroysis issues with copper bottom coatings are due again to stray currents (leaking 12V DC or 120V AC shore power).

I utilized CopperPoxy on the Saratogan over two coats of epoxy barrier coat.
CopperPoxy is copper flakes in epoxy resin. I think the copper is about 60%. It's a hard nonsloughing coating designed to last 10 years with only annual pressure washing. There was a warning on the label concerning potential electroysis issues and suggested the owner check the color of the coating from time to time. So far so good, but I've only been in the water three months.

California may be banning copper bottom paints in the future. Not sure where that is at at the moment? I'll do a little research and find a book ot two on the subject. Marine Metals Manual and Corrosion Workbook come to mind.

A couple years back I was working on a sizable wood schooner. I got many of the plumbing and electrical issues worked out. The owner then took the boat to Port Townsend to have a couple of stansions replaced. On inspection, all of the stansions needed replacing. The two upper planks were removed from the hull to gain access as well as the two outboard deck planks.

The square iron nails holding the hull planking on were half gone and the hole in the planking was "burned" by the electrolysis of the iron and salt in the wood. Most of the nail holes in the planks were three times normal size.

The yard removed a few more planks lower and near the bow to add a few sister frames. It was then discovered that the stem was rotten. The old stem was removed with a spoon and a new stem fashioned from patterns made. The new stem was probably 12-14 feet long and from Port Orford cedar. I think that piece of lumber alone was $1200 or thereabouts.

The tanks (four fuel and four water) were discovered to be bad. More deck planks were removed to get the old tanks out. New tanks were made. A new main mast was built, and the lower section of the forward mast was scarfed in. New standing rigging, new running rigging and new sails. Then the economy went south and the project was put on hold. I think the bill for all this was projected to be a half-mil.

So find a good surveyor, find out what his vices are and then feed those vices. Give the surveyor ANYTHING he wants (save your first born). That survey will be worth it's weight in gold!

[Tim_Mattson]

Ed ,
I just went to Antioch to help a buddy retrieve a Glass powersailor that was moored on the Delta.
After hearing the owner talk of cooling troubles and all he replaced after a clogged inlet blocked off water flow.
Seems the Braziliean Sea Grass that is now infesting that area after being pumped out of a Ship Bilge.
I`d look for signs of overheating on the block of any engine you think of buying in that area.
Then hire the surveyer to look "inside" a little deeper.
Looked like every other boat was for sale with every other slip empty at Owl Marine where we picked up the old Albin cruiser.
Love that Levee Road" with all the repairs and soft shoulders.
My fingers are still white.
TimM

[Cosmic Consciousness]

Ed ,
I just went to Antioch to help a buddy retrieve a Glass powersailor that was moored on the Delta.
After hearing the owner talk of cooling troubles and all he replaced after a clogged inlet blocked off water flow.
Seems the Braziliean Sea Grass that is now infesting that area after being pumped out of a Ship Bilge.
I`d look for signs of overheating on the block of any engine you think of buying in that area.
Then hire the surveyer to look "inside" a little deeper.
Looked like every other boat was for sale with every other slip empty at Owl Marine where we picked up the old Albin cruiser.
Love that Levee Road" with all the repairs and soft shoulders.
My fingers are still white.
TimM

Wow, Tim...it's a small world! My boat was berthed at Owl Harbor, three three slips away from the Albin. I moved it to Walnut Grove in late September. The weed infestation isn't nearly as bad in the north stretch of the delta. But on the other hand, I'm now dealing with shallow depths in my new location, so I'm not sure which is worse...haha...

That was a great Albin, but there weren't enough people out there who really appreciated them, which is why it sat on the market for such a long time. Many people looked at it and said "Wow, that's an old slow boat for $12500. For that price, I can get a sleek Sea Ray!" It really needed to go to someone who understood and appreciated the Albin motor sailor. In case your friend hasn't come across this site, here's a good Albin blog with a wealth of information about that boat: http://www.albin25.eu/ .

The cooling issues on that boat were preceded by transmission problems. The owner didn't have time or impetus to give it the love it needed. The owner was elderly and from talking to him, he had lost every single ounce of motivation to maintain it. I'm glad its in good hands now.

With that said, yes...the weed issue has made marine mechanics all over the delta very happy. If I stayed in that part of the delta, I would have designed and fabricated an auxiliary raw water intake system with an electric pump that would automatically be activated when the engine temp exceeds 180.

I do plan on hiring a surveyor. With my lack of knowledge of wood hulls, failing to hire a surveyor would be futile.

[Tim_Mattson]

Ed ,
Martin took us to lunch at Pirate Cove and we listened to his story on the repairs and his situation.Super nice guy and as a small plane pilot/owner ,he took the same care in the Albin repairs.
The inside was stunning and with basically a new Volvo MD Engine and tranny,it will need to be broken in.
My buddy works on newer,bigger Swedish-built Albins at a Boatyard in Seattle but knows very well what a Treasure he has.He also is very worthy of it too.
We ended up sleeping in the boat along I-5 on the way home after my lil` truck cried foul over some Injector cleaner.His wife predicted HE`d be sleeping in it,I wasn`t supposed to get to until we went to the San Juans....
1000 mile drive and 3 boats away....too funny.
TM

[Cosmic Consciousness]

Ed ,
Martin took us to lunch at Pirate Cove and we listened to his story on the repairs and his situation.Super nice guy and as a small plane pilot/owner ,he took the same care in the Albin repairs.
The inside was stunning and with basically a new Volvo MD Engine and tranny,it will need to be broken in.
My buddy works on newer,bigger Swedish-built Albins at a Boatyard in Seattle but knows very well what a Treasure he has.He also is very worthy of it too.
We ended up sleeping in the boat along I-5 on the way home after my lil` truck cried foul over some Injector cleaner.His wife predicted HE`d be sleeping in it,I wasn`t supposed to get to until we went to the San Juans....
1000 mile drive and 3 boats away....too funny.
TM

Yes... He is a super nice guy. When he talked about the boat's past, it was impressive. He just came across as having lost any desire to keep enjoying it. In the two years I had berthed my boat at that marina, I had never seen the Albin taken out of its slip (or washed, for that matter). It really needed a new home. I knew about Albins and really appreciated them; and when I saw this one just sitting there and not living up to its potential, it made me sad. I knew it was going to be hard to sell it locally -- since the market for classic motor sailors is not as strong in the delta or Bay Area as it would be in the PNW.

I'm happy to see it went to an excellent home and in the hands of someone who will make her shine!

Sorry to hear about the hiccup with the truck not liking the fuel injector cleaner. But hey, it's a part of the adventure! And yes, three boats away and a thousand miles apart...I've seen stranger connections, but this is pretty far up there with them!

[Cosmic Consciousness]

Silicon bronze is one of many alloys of copper. Specifically, it is 95% copper, 4% silicon, 1% manganese. It has similar strength to mild steel, but is considered very corrosion resistant.

Corrosion issues in silicon bronze fastened plank-on-frame hulls is probably fairly rare and the cause is likely to be stray current from a leaking shore power connection either on the subject vessel or one moored close (a marina issue)

It's not the fresh water that is a problem, but all the little critters that live in it. A boat that is moored in fresh water under cover shouldn't have rot issues if the boat is maintained to any degree. Nonetheless, it would be a good idea to hire a marine surveyor with wood boat experience if you were serious about purchasing an older wood boat of any size.

The electrical conductivity of copper bottom paints is an interesting issue and I would like to know more about it. Like the fastener issue, I believe that most electroysis issues with copper bottom coatings are due again to stray currents (leaking 12V DC or 120V AC shore power).

I utilized CopperPoxy on the Saratogan over two coats of epoxy barrier coat.
CopperPoxy is copper flakes in epoxy resin. I think the copper is about 60%. It's a hard nonsloughing coating designed to last 10 years with only annual pressure washing. There was a warning on the label concerning potential electroysis issues and suggested the owner check the color of the coating from time to time. So far so good, but I've only been in the water three months.

California may be banning copper bottom paints in the future. Not sure where that is at at the moment? I'll do a little research and find a book ot two on the subject. Marine Metals Manual and Corrosion Workbook come to mind.

A couple years back I was working on a sizable wood schooner. I got many of the plumbing and electrical issues worked out. The owner then took the boat to Port Townsend to have a couple of stansions replaced. On inspection, all of the stansions needed replacing. The two upper planks were removed from the hull to gain access as well as the two outboard deck planks.

The square iron nails holding the hull planking on were half gone and the hole in the planking was "burned" by the electrolysis of the iron and salt in the wood. Most of the nail holes in the planks were three times normal size.

The yard removed a few more planks lower and near the bow to add a few sister frames. It was then discovered that the stem was rotten. The old stem was removed with a spoon and a new stem fashioned from patterns made. The new stem was probably 12-14 feet long and from Port Orford cedar. I think that piece of lumber alone was $1200 or thereabouts.

The tanks (four fuel and four water) were discovered to be bad. More deck planks were removed to get the old tanks out. New tanks were made. A new main mast was built, and the lower section of the forward mast was scarfed in. New standing rigging, new running rigging and new sails. Then the economy went south and the project was put on hold. I think the bill for all this was projected to be a half-mil.

So find a good surveyor, find out what his vices are and then feed those vices. Give the surveyor ANYTHING he wants (save your first born). That survey will be worth it's weight in gold!

Thanks for your input, Tim. Copper based antifouling paint has been contentious in California as far as I can remember. And in the California Delta, bottom growth is not as much of an issue as it would be in salt water. That's why I've been comfortable with the lower copper content paints. I've seen them as high as 50 percent, which is pretty close to just attaching copper paneling to the bottom of the boat and calling it a day, lol...

The case of the wood schooner needing a bigger makeover than the owner could imagine is very telling. There are plenty of hot marinas in the delta. The first boat I owned was a victim of a hot marina. A month after taking ownership, the u-joint bellow of the starboard outdrive developed a leak. When I pulled her out of the water, this is what I realized I purchased:



I was, of course, new to boating back then and was completely oblivious to the consequences of galvanic corrosion. Luckily, the cavitation wasn't serious enough to compromise the casing, and tons of epoxy along with four layers of outdrive paint rescued them.

And yes, I purchased the boat without getting a survey. The "good deal" ended up biting me where it hurts. While I now know enough about fiberglass hulls to not need a survey in a boat purchase, the world of wood hulls is a different story. I will find the surveyor's vices and generously feed them!

Just a quick question... Will an experienced surveyor be able to get a good feel for the condition of the hull while the boat is still in the water? I'm not trying to save the cost of the haul-out; rather, I'm looking at it in terms of practicality, since some of the boats I've seen are 10 or so nautical miles from the closest haul-out facility. And to make an offer contingent upon the seller taking the boat 10 nautical miles to the facility, spending two to three hours there for the survey, and taking the boat back might be a bit too much to ask...even in this market.

[McSkagit Tim Jones]

In water survey?

Ed, It's your call since you would likely be paying for the survey.

I had an in-water survey done some years back on my Glasply tow boat. Surveyor usually will make a disclamer that certain parts of the boat were not inspectable.

Wood boats are a bit more important to check the hull, calk, fastenings, through-hull fittings etc.
Today I think they use an ultrasonic device in addition to an awl. Maybe pull a couple of plank fastenings to see what they look like.

Depends on the size of the boat and investment. I'd have it hauled and given the complete going-over.

Some insurance companies won't insure wood boats at all. Some companies specialize in classic wood boats and require a detailed survey. Check Hagarty Classic Boat Insurance to see what they want..

My two cents worth..

[Cosmic Consciousness]

Thanks for the info, Tim. I contacted Hagarty Insurance and they do require a recent out of water survey and are very picky about who performs the survey (as in the surveyor being unaffiliated with a brokerage or insurance company). I guess that answers the question as to whether an in-water survey is even an option.

Thanks again. Now on to crossing paths with the right boat...

[McSkagit Tim Jones]

Banning Copper Bottom Coatings!

Just read a story that Washington may be the first state to ban copper bottom paints. The Northwest Marine Trade Association (NMTA) is proposing a bill that would prohibit the use of copper-based bottom paint after a specified time period, possibly 15 years.