Most Reliable Hull Construction ?

[psneeld]

Originally Posted by lorenzoSF

Mmhm, so what would you guys recommend?

Dockhead and Blue_stockings, what would be your recommendation on how to make sure the build quality is right?

Psneeld, can you send some links on hydrolysis? If the "life of the boat" is important, what life should she live? Are you implying it should not be left in warm water 100% of the time? That was more or less my plan, cruising in warm places most of the time, so I'd like to know if it is a problem.

Lorenzo

If you have a sound hull...the more you can do to slow the ingress of water (hydrolysis) the better. Epoxy made for water blocking (not all do from what I've read) should be used as a barrier coat..the thicker the better. Warm water accelerates the process but if you stay there...then the other blockers like a thick barrier coat or getting her out of the water every now and then and keeping the inside dry all help.

Just google hydrolysis and you'll have al the reading you want...like I said...go beyond just boat resin/composite problems...In my mind...the marine business for the most part is usually at least a decade behind the rest of the world.

[Adelie]

Why the cat? You have expressed concern about cost. For the same price as a newer cat you can get an older monohull that has just as much interior volume.

How much sailing experience do you have?
How many kids have you got?
How old are they?
Do you mostly intend to liveaboard with occasional cruises, or do you want to cruise a lot?
Where do you want to visit?

[delmarrey]

Originally Posted by Adelie

Why the cat? You have expressed concern about cost. For the same price as a newer cat you can get an older monohull that has just as much interior volume.

How much sailing experience do you have?
How many kids have you got?
How old are they?
Do you mostly intend to liveaboard with occasional cruises, or do you want to cruise a lot?
Where do you want to visit?

Ask the wifie.
It's the motion in most cases. Some can not take the healing of monos and some can not take the banging of a cat.

[Target9000]

Originally Posted by lorenzoSF

Mmhm, so what would you guys recommend?

Dockhead and Blue_stockings, what would be your recommendation on how to make sure the build quality is right?

Psneeld, can you send some links on hydrolysis? If the "life of the boat" is important, what life should she live? Are you implying it should not be left in warm water 100% of the time? That was more or less my plan, cruising in warm places most of the time, so I'd like to know if it is a problem.

Lorenzo

Hey Lorenzo,

As I stated in my first reply to you... If you pick a fiberglass hull, blisters will be at the top of your maintenance list. Psneeld is right when he said all fiberglass boats experience hydrolysis, however it is misguiding. All metal boats experience electrolysis. All wood boats are rotting. The fact of the matter is that it is manageable.

There are giant debates that end up getting very confusing on blisters, blister repair, hydrolysis, etc. At the most basic level, over time, water will wick its way into fiberglass hulls causing them to swell with blisters. To prevent this and extend the life of the boat an owner has three primary weapons.

1) The barrier coat. - You paint the bottom of the boat with a thick coat of epoxy designed to slow down the progress of hydrolysis. This is much easier done on a new boat or one that hasn't been in the water for many years as you want the boat "dry" when you do it.

2) Blister repair - If you find a blister during a haul out, you address it properly. This is normal maintenance.

3) Keep the inside of the boat dry. Good ventilation and keeping water out of the bilges will help.

These things are not rocket science and they're not hard to accomplish. A lot of people saber rattle over them, but don't be deceived. A quick walk around almost any marina in the world where small pleasure yachts are kept will reveal what the most enduring and lasting material used in the world today is. Like I said, if you take care of it.... Its going to outlast YOU.

Now don't get me wrong, this isn't said to knock metal boats. Or even wooden boats. Buy a quality boat from a quality builder and maintain it, and it will last. I'll concede Psneeld's point that fiberglass won't last forever, but I'll add on, it will outlast US.

[psneeld]

Originally Posted by Target9000

Hey Lorenzo,

As I stated in my first reply to you... If you pick a fiberglass hull, blisters will be at the top of your maintenance list. Psneeld is right when he said all fiberglass boats experience hydrolysis, however it is misguiding. All metal boats experience electrolysis. All wood boats are rotting. The fact of the matter is that it is manageable.

There are giant debates that end up getting very confusing on blisters, blister repair, hydrolysis, etc. At the most basic level, over time, water will wick its way into fiberglass hulls causing them to swell with blisters. To prevent this and extend the life of the boat an owner has three primary weapons.

1) The barrier coat. - You paint the bottom of the boat with a thick coat of epoxy designed to slow down the progress of hydrolysis. This is much easier done on a new boat or one that hasn't been in the water for many years as you want the boat "dry" when you do it.

2) Blister repair - If you find a blister during a haul out, you address it properly. This is normal maintenance.

3) Keep the inside of the boat dry. Good ventilation and keeping water out of the bilges will help.

These things are not rocket science and they're not hard to accomplish. A lot of people saber rattle over them, but don't be deceived. A quick walk around almost any marina in the world where small pleasure yachts are kept will reveal what the most enduring and lasting material used in the world today is. Like I said, if you take care of it.... Its going to outlast YOU.

Now don't get me wrong, this isn't said to knock metal boats. Or even wooden boats. Buy a quality boat from a quality builder and maintain it, and it will last. I'll concede Psneeld's point that fiberglass won't last forever, but I'll add on, it will outlast US.

Nice post..all good points.

You are dead on saying it's manageable.

The problem is VERY few people realize how quickly things can go south and don't even realize their boat could be deteriorating way faster than they think..... and don't think the surveyor's, or the yard's or their best buddies advice is worth a crap. The only way to know the extent of hydrolysis is to grind int it or core sample.

[Blue Stocking]

It is difficult to determine the quality of the build as certain ages and stages of boat development came with different problems.
During the 70s oil shortage, some really poor resins were used.
Then came the "binder" problem with Fabmat use.
There was an investigation into boats ( I honestly can't remember which manufacturer) which exposed an unusually high quantity of gelcoat to lay-up seperations on the same sideof the hull. Turned out that the lay-up schedule was not being mirror-imaged, but similarly scheduled from the gelcoat inward.
Early balsa cored Down-East type fishing boats often experienced leakage around the rudder stuffing box into the core, caused by the skeg- bottomed rudder working against the hull. Balsa mush. Likewise under their spray rails at the stem.
Higher quality cored boats would (should) have the core cut back in the area of all thru-hulls,stem, topside to transom junctions, chainplates, engine bed to hull points, so that the inner and outer skins can be brought together.
Wood bulkheads to which chainplates are bolted, should be cut away from the underdeck and sealed so that chainplate-area leaks do not allow water directly into the edge grain.
Look in the chain locker and see how far onto each side the overlapping lay-up are carried.
If the boat was laid up using chopper guns, try to find a few areas where you can expose the lay-up.
Most 70s and 80s boats were chopped using a 4 bobbin feed. 3 white ,1 colored (we used red) so that you could see the laydown of mat. Look closely, and if the fibre are individually visible in the lay-up, then the hull could be resin-poor, or not adequately rolled-out.
Look for consistency in the red tracer, indicating consistant thichness between chop and roving.
Just a few of the things which come to mind.
On a personal note about longevity, Blue stocking was launched July 1st 1965.
She has belonged to personal friends before I aquired her in 1994, so I know her entire history.
She has a layup totalling 14 alternating 2 oz chop,and 24 oz roving from rail to turn of bilge, 24 in the turn, 28 over lapping up 2ft the other side thru the keel area.
When I rebuilt her from any empty shell, I groung off all the old interior paint.
Chinese characters were visable all over the lay-up, which a friend read as the layup notes.
I barrier coated her in 1996, not because she needed it, but because I was giving her a complete rebuild. 10 coat of Interprotect. Not a blister to this day.

[psneeld]

Originally Posted by Blue Stocking

It is difficult to determine the quality of the build as certain ages and stages of boat development came with different problems.
During the 70s oil shortage, some really poor resins were used.
Then came the "binder" problem with Fabmat use.
There was an investigation into boats ( I honestly can't remember which manufacturer) which exposed an unusually high quantity of gelcoat to lay-up seperations on the same sideof the hull. Turned out that the lay-up schedule was not being mirror-imaged, but similarly scheduled from the gelcoat inward.
Early balsa cored Down-East type fishing boats often experienced leakage around the rudder stuffing box into the core, caused by the skeg- bottomed rudder working against the hull. Balsa mush. Likewise under their spray rails at the stem.
Higher quality cored boats would (should) have the core cut back in the area of all thru-hulls,stem, topside to transom junctions, chainplates, engine bed to hull points, so that the inner and outer skins can be brought together.
Wood bulkheads to which chainplates are bolted, should be cut away from the underdeck and sealed so that chainplate-area leaks do not allow water directly into the edge grain.
Look in the chain locker and see how far onto each side the overlapping lay-up are carried.
If the boat was laid up using chopper guns, try to find a few areas where you can expose the lay-up.
Most 70s and 80s boats were chopped using a 4 bobbin feed. 3 white ,1 colored (we used red) so that you could see the laydown of mat. Look closely, and if the fibre are individually visible in the lay-up, then the hull could be resin-poor, or not adequately rolled-out.
Look for consistency in the red tracer, indicating consistant thichness between chop and roving.
Just a few of the things which come to mind.
On a personal note about longevity, Blue stocking was launched July 1st 1965.
She has belonged to personal friends before I aquired her in 1994, so I know her entire history.
She has a layup totalling 14 alternating 2 oz chop,and 24 oz roving from rail to turn of bilge, 24 in the turn, 28 over lapping up 2ft the other side thru the keel area.
When I rebuilt her from any empty shell, I groung off all the old interior paint.
Chinese characters were visable all over the lay-up, which a friend read as the layup notes.
I barrier coated her in 1996, not because she needed it, but because I was giving her a complete rebuild. 10 coat of Interprotect. Not a blister to this day.

Many boats that were in good shape before a good barrier coat will be in good shape for a long time....BUT...no blisters doesn't mean hydrolysis isn't going on and a LOT of experienced boaters thought my hull was fine right up to the point of digging my knife in and peeling off layers of glass by hand.

Not saying ANY particular boat is in trouble...but you don't know for sure till you dig deep (no pun intended)

[Blue Stocking]

Originally Posted by psneeld

Many boats that were in good shape before a good barrier coat will be in good shape for a long time....BUT...no blisters doesn't mean hydrolysis isn't going on and a LOT of experienced boaters thought my hull was fine right up to the point of digging my knife in and peeling off layers of glass by hand.

Not saying ANY particular boat is in trouble...but you don't know for sure till you dig deep (no pun intended)

Emphatically So

[Dockhead]

Originally Posted by lorenzoSF

Dockhead and Blue_stockings, what would be your recommendation on how to make sure the build quality is right?

Reputable boat builder with demonstrated track record of building cored hulls without problems. Can't advise you who, in particular, among catamaran builders, as I don't know cats that well, but I'm sure someone will pipe up.

[lorenzoSF]

Originally Posted by Adelie

Why the cat? You have expressed concern about cost. For the same price as a newer cat you can get an older monohull that has just as much interior volume.

How much sailing experience do you have?
How many kids have you got?
How old are they?
Do you mostly intend to liveaboard with occasional cruises, or do you want to cruise a lot?
Where do you want to visit?

Well cost is of course one of the factors for anyone who is not a billionair.
I understand that monohulls are cheaper, but there are several reasons why I prefer a cat:
1) as guessed by Delmarrey my wife doesn't take well the monohull motion
2) space both inside, cockpit and trampolines
3) I just like them better

To answer your questions:
- not a lot of sailing experience. I like sailing, but the main point is to be able to live wherever I want anytime I want and of course visit wonderful places
- I have 2 kids, 12 and 1 yo, so for a few years it will be liveaboard 9 months out of 12 somewhere they can go to school (probably a different place every year) and cruising the remaining 3 months. After the kids are out I would spend more time cruising.


Thanks to every one for the great suggestions and info!

[Sand crab]

These production cats seem to have less core issues.
Outremer because they are solid glass so no core
Manta
Seawind and they probably have the best factory backup.
Catana except for around the year 2000. They had some issues back then but still less than most.
The Lagoon 35, 37, and 42 were built in the US by TPI with a patented infusion process and are known to be some of their best boats and have yacht grade interiors. And affordable.

There are lots of customs built with epoxy/foam or epoxy/wood. Give these a good look because no-name boats are almost always more affordable and as I said before epoxy is a good thing.

Good luck BOB

[Wellington]

Originally Posted by lorenzoSF

I would like to know what is the best construction material for the long long term and ideally what specific cat you would suggest (keeping in mind 1. durability/safety, 2. living space, 3. performance).
Thanks
Lorenzo

We had the same criteria. We bought a Lagoon 440 and love it. I read here on CF and on other forums that the Lagoon 440 was a great boat, solidly built, safe and very spacious, with 2 drawbacks:
1. it is slow
This is just not true. In our experience we are faster on all points of sail (but close hauled) than 90% of 30-50ft monohulls. We've already hit 14.6 knots, feeling totally safe.
2. it has a flybridge
Again, I assume that those who criticized the flybridge never tried it. It is fabulous. 6-7 persons can fit there. The view is great, including for young kids who can steer (as the wheel is at their height). It is a great place to do night shifts (you can lie while keeping watch). If need be (45+ kts of wind, cold climates, pouring rain...) you can steer from the navigation table as well