Woody owner advise needed - hull

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rsn48

Guru
Joined
Feb 18, 2019
Messages
2,019
Location
Canada
Vessel Name
Capricorn
Vessel Make
Mariner 30 - Sedan Cruiser 1969
My boat has a wood hull with fiberglass over the outside as an original build. I've gutted the boats bilge completely, tanks and all, so that the area is down to bare hull inside. Sort of the bottom 1/3rd has been repainted in the area that holds any bilge water that makes its way in.

The whole boat stripped down has shown very little rot or anything except for one tiny area in the hole in the transom where the leg for I/O comes out of for the engine. The hole has been glassed back in with the one tiny rot area dug out and epoxied in then glassed over at the transom. A new hole will be cut out for the new leg going in.

I have debated whether to paint the rest of the interior hull in the bilge area just for protection. The boat is 50 years plus and seems to have weathered time rather well.

Should I paint over the old paint after washing down, it doesn't really need it but this will be the last time the entire bilge area of the hull will be exposed as fuel, water and other stuff will be installed. I'm trying to decide if I am being paranoid about a problem or not, my refit guy thinks the hull is fine and his crew would be the one painting it so he is denying himself money.
 
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I don't think it is a problem, but like you, I would do it and in fact did do it. When I repowered my 1965 TollyCraft Voyager which had a plywood hull covered in glass, I cleaned, primed and painted the entire bilge myself. I live 120 miles each way from my boat and did the work on weekends and have zero regrets.
Go for it.
 
You didn't mention fasteners. Hull fastener condition should be assessed.
 
Hull fasteners have been checked out. Everything is amazingly fine.
 
Depends on how long you plan on keeping it and if the hull is plywood, carvell planked etc.

A lot depends on if the boat is trailered and allowed to dry between uses or seasonally. Or the boat sits in a slip in fresh or saltwater all year.

If long term ownership is planned, I'd take the interior down to bare wood, let it dry and coat it with two coats of epoxy resin then paint.

You don't want bilge water and other moisture soaking into the wood in the bilge. If the moisture goes through the wood and reaches the glass sheathing, problems like delamination and blisters may develop. With planks, moisture will swell the wood and may crack at the seams.
 
If long term ownership is planned, I'd take the interior down to bare wood, let it dry and coat it with two coats of epoxy resin then paint.

This was done to the bottom third of the hull to maintain hull integrity.
 
I've been in I've been in boat and ship building and repair for many years. I owned a boatyard. One common problem I've seen in fiberglass over wood is wood rot when the hull isn't kept dry. Either you keep the wood dry or preserve it in some way. Considering where you are I assume your hull spent it's life in salt water. That's probably why there is little rot. If the wood in the bilge is going to be wet, you should keep rock salt or borate in the bilge as a preservative.
Also a lot of rot comes from deck leaks. In the days before fiberglass was common, larger boats of the time had salt boxes along the top of the hull, between the ribs. Moisture that collects under the deck runs to the sides (in a properly curved deck). It flows thru the salt boxes and down the inside of the hull, preserving the ribs and planking. In places where old wood ships are rotting away, you'll see their ribs sticking up from the mud. Decks are usually long gone, but the ribs and planking often still survive because of the salt boxes.
I assume in Canada, like the US, wood preservatives that actually work are now illegal, that leaves salt.
 
The build of this boat overall has been commented by a few in the industry with all the same observation, it was very well built. Now having said that, it also had something so incredibly stupid it defies the mind.

About an hour after I purchased the boat, I started thinking - I don't recall seeing any scuppers, where does the water go from the cockpit. So later I went to the boat and dumped a pitcher full of water in the cockpit and it ran to both sides and disappeared into the bilge. Now I live in coastal BC where it rains, and it can rain a lot. I have been told the boat was built in Vancouver bc where it rains even more. So how can you build a boat without scuppers?

The sides of the cockpit was peg board thus letting the rain in as well. This peg board has been removed and old motor vent thru hulls are being converted into scupper drains. The new motor vents through the leg.

The boat was gutted except for the engine. Everything was intact, no rot, mold, etc. I was very surprised. But I was worried what would be beneath the engine. Once the engine was removed and the old leg taken out, the only rot slightly smaller than a baseball hard ball was in the transom. This was cleaned out and epoxied, etc and the area reglassed for the new hole for the new leg.

The area under the motor was power washed and cleaned out and let dry for a couple of weeks. It was "clean" with no rot. It has now been epoxied and painted, etc.

There was peg board inside the boat, slightly ugly but as my refit guy said, it allowed the boat to breath and was probably one of the reasons it didn't have damage.

The boat did leak through the stanchions and I expected rot there, the deck is wood. But again to my amazement, nothing.

The covering on the top roofs over the V birth, galley and salon were all stripped of what the crap was used to cover it, kind of like a vinyl paper. The deck was wet underneath but in tact, no rot. The decks and cockpit area was dried out for a month then the entire area epoxied, and PlasDECK is going in. Templates have been made, waiting for delivery now.
 
Another opinion re the bilge coating.
In the book “Skiffs and Schooners” by Peter Culler he says he put kerosene liberally throughout the inside of all new boats he built. He mixed Linseed oil w the kerosene and the idea behind the kero is that it becomes a vehicle to “drive the oil into the wood”. One can mix various poisons like zinc, Tea Tree oil, ect ect to control rot and mildew. Commercial wood preservatives can be used but much of what’s on the market is rather harmless.

If you put epoxy there you’ll never be able to do much of anything w it in the future.
 
If you put epoxy there you’ll never be able to do much of anything w it in the future.

That's the point. Preserve the boat with minimal upkeep.

I can't imagine what someone might want to do later that epoxy will prevent.
 
Linseed with kerosene would stink. But it also sounds like a treatment used on "raw" wood, unpainted. The wood on this boat has been painted, but a long time ago, except for the bilge area which was done last week.
 
To preserve wood it needs to be out of the rot zone.Too wet or too dry.
Leaks are the horror as the boat will pass from wet to dry slowly.

NO deck or other leaks works well , but it requires constant inspection and immediate action on discovering a drop of water. MR Herrishoff felt open airways to ventilate the hull up to the deck covered with a loose ceiling was key.

When wood is water saturated it is too wet for dry rot. Salting when not in use was the classic for smaller fish boats , usually built of less expensive lumber.

For a liveaboard the challenge of a true dry boat is a full time job , but easier to live with than a wet dripping salted interior.
 
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Linseed with kerosene would stink. But it also sounds like a treatment used on "raw" wood, unpainted. The wood on this boat has been painted, but a long time ago, except for the bilge area which was done last week.

“Stink” ... yes it would ... for a little while. And is best applied to bare wood.
 
That's the point. Preserve the boat with minimal upkeep.

I can't imagine what someone might want to do later that epoxy will prevent.

The point is that no matter what you apply over wood water will get around it in time and rot the wood. This boat does seem a bit of a miracle and never seen a miracle before. Put varnish epoxy or whatever on a cap rail and later black streaks will appear wherever there is a fastener or joint. That’s where the water got under the coating and mould has developed.
Epoxy seals most of the wood. The rest will suffer from water ingression.

syjos also wrote;
“I can't imagine what someone might want to do later that epoxy will prevent.”
Most of the wood covered w epoxy would remain so. And anything like teak oil or wood preservative would not get to the wood to preserve it.
 
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Encapsulating the total interior of the boat with 2 coats of epoxy will prevent water intrusion. The frames and their contact area with the hull needs to be coated with epoxy.

The bilge area needs special attention. I insert pvc pipe cut in half into the limber holes with lots of epoxy, add additional limber holes where water might accumulate and filet the frame to hull joint. Any hollow or low spots in the bilge area where water can collect should be leveled with epoxy putty.

I restored a few old wood boats in the early 80's coating the insides with WEST epoxy as described and fiberglassing the exterior. I was able to visit two of them a few years ago and both were in good condition without any water intrusion issues. One boat is on a mooring buoy 7 months a year and the other is wet moored.

On any epoxy encapsulated wood boat you have to be vigilant keeping the interior dry. Any breaks or holes in the interior coating needs to be recoated.
 
wood balm

I had a beautiful classic cruiser 45 foot carvel hull built in 1929 and a brew that an old shipwright recommended for any bare wood/breached paint and also as a pre painting primer was 50/50 gum turpentine and raw linseed oil mixture. I used it a lot ,inside cupboards, under bunks and anywhere that it was a bit humid and I wanted to stop mould or damp and it smells great.Would agree that products like epoxy resin and particularly sealers like Everdure are fantastic, but were not around in the old days and as most of these rely on fairly pristine conditions to work at their full efficiency , oily old bilges would be unlikely to receive them, whereas this stuff you can just slap around and it will soak in wherever there is paint missing and give plenty of coats until the timber stops taking it up.
 
Some old wooden boaters use something called "boat soup" or "boat sauce". It is a mixture of Turps, Linseed Oil, Varnish and Stockholm tar. I have used it, smells great and seems to last in protected areas.
 
Considering the age of the boat and the lack of rot, it may have benefited from a preservative now illegal. About that time there was a 2 part application water soluble solution of copper and arsenic. It worked well on both dry and wet wood. In a test plot in the Panama Canal Zone jungle, 2x4s half in the ground survived 50 years in good condition while untreated wood was gone in 3 years. Also, cuprinal (as it existed then) also went 50 years, but tinted the wood green. My current wood boat, built in 1942, was treated after the war and still has an excellent hull with an absence of rot.
 
All those old timey solutions and elixirs for wood preservation are just that, old timey requiring constant attention.

My ultimate solution for my wooden Grand Banks was 600 dollars worth of Clear Penetrating Epoxy painted onto the sand blasted exterior and dumped by the gallon into the dried out bare wood bilge. Problems with wood boring organisms and and rot over. In its 47-year existence, it has never needed a new strake.
 
Lepke I remember the “Cuprinal” and green plywood.
There’s nothing like it now that you can buy.
Wonder if you could mix powdered zinc into turp and raw LO?
I’ve always heard linseed oil was fungus food. I use it quite often and haven’t made anything rot.
 
I use to buy cuprinal in 55gl drums. The trick to stopping wood rot is kill the fungus that causes rot and the organisms that eat into the wood. Heavily salted wood will resist both, but not as well as what we had.
 
Once again, boat as a tub full of chemicals and microbes - out to get you.


Thanks for the link.


"The smell is surprisingly refreshing."
 
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I once sprayed Cuprinol into the upper reaches of my wooden trawler's lazaret because it was a known area of deck leaks in the boat, and I REGRETTED it for years until the stink wore off. I would say it was a case of too much of a good thing.
 
Lepke I remember the “Cuprinal” and green plywood.
There’s nothing like it now that you can buy.
Wonder if you could mix powdered zinc into turp and raw LO?
I’ve always heard linseed oil was fungus food. I use it quite often and haven’t made anything rot.


I bought a gallon of Cuprinol a couple of years ago. Vile smelling stuff!!! You can (or could) still get it in Canada. A fellow at the end of my block built a deck 2 years ago and slathered it in Cuprinol. You could smell the house 4 doors down for months. Not anymore though.

Jim
 
Yes but the Coup worked.
Many would liberally coat/soak the entire inside of of a new hull.

Jim,
You say you can buy it in BC?
Must be a watered down version ....
 
Never seal in wood hull with epoxy. Moisture will get in then rot will start. Paint great deal up with epoxy no.
 
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