Lipari 41: Hull

[CaptRehab]

Depending on the review I read I get slightly different information. I have read that the deck is fabricated using a Resin Transfer Moulding (RTM) Technique, and that the hull is fabricated using a Vacuum Infusion Technique. In both cases it would appear that they are not using hand layup for major components. Since I have also read that isophthalic polyester resin is used, I would have to assume these techniques require 100% isophthalic resins are used.

Often you hear of hand layup hulls having an outer isophthalic resin to act as an osmotic barrier with orthophthalic resins used on inner layers.
This would seem to be done for cost because not only does the isophthalic resin have better resistance to osmosis, but tensile strength 11 ksi vs. 8 ksi and flexural strength 19ksi vs 12 ksi is superior to orthophthalic resisns. Tensile and flexural modulus for both are close to the same.

I guess a trip to the factory to talk to the engineers may be the best way to get an anwser before putting money down.

I would love to hear opinions and facts about FP construction methods both older and current.

[CDunc]

Im going to have to agree that the use of orthophthalic resins is a cost issue. Lots of reasons for saying this, mostly having to do with labor and materials. Given the choice and money, ill take the vacuum infusion or pre preg due to the higher glass to resin ratio thank you.

[CaptRehab]

Properly done these methods should be superior to hand layup, and the iso resin should make the hull stronger but not stiffer.

I would love to see what process controls they employ.
Do they test for voids?
How do they fix one if they get a void?
How do they insure the proper laminates are where they should be.
Do they do any QC tests when it comes out of the plug?

I heard that someone once asked Olin Hunt if he were to take a boat out to the open ocean, who would he want the boat to be designed by. The response was he would be more concerned by who built it.

[GordMay]

Originally Posted by CaptRehab

... I heard that someone once asked Olin Hun ...

I heard that someone once asked Sam Gunch the same question. He replied "GordMay".
Who is Olin Hunt.
Who is Sam Gunch?

[CDunc]

The resins arent contributing as much to the strength or stiffnes as the Laminate design of the panels. I would be more concerned as to the direction, type and weight of the roving in relation to the stresses.

[muskoka]

The best bet would be to go directly to FP for this information. Gregor Trajan of Aeroyachts in Long Island may be a good source of info if you can't visit the factory or negotiate French technical documents. He's an FP dealer who also wrote a reference book titled Catamarans. The web site is: Aeroyacht Catamaran News

I can't imagine most owners have such detailed knowledge pertaining to resin types, etc. I know our hull was resin infusion "vacuum bagged" and the layup appears to be remarkably consistent and free of voids - which I suppose is the objective. Well, that and saving costs by not squandering resin.

[CaptRehab]

Originally Posted by muskoka

The best bet would be to go directly to FP for this information. Gregor Trajan of Aeroyachts in Long Island may be a good source of info if you can't visit the factory or negotiate French technical documents. He's an FP dealer who also wrote a reference book titled Catamarans. The web site is: Aeroyacht Catamaran News

I can't imagine most owners have such detailed knowledge pertaining to resin types, etc. I know our hull was resin infusion "vacuum bagged" and the layup appears to be remarkably consistent and free of voids - which I suppose is the objective. Well, that and saving costs by not squandering resin.

I have Gregor's book and have talked to him. He does not have this info, but I probably will arrange a factory visit through him. Chris White's book is another good book with probably more technical details than Gregor's

[CaptRehab]

Originally Posted by CDunc

The resins arent contributing as much to the strength or stiffnes as the Laminate design of the panels. I would be more concerned as to the direction, type and weight of the roving in relation to the stresses.

Absolutely correct. But I am assuming the hulls of all the catamarans from the major manufacturers are properly engineered. What I am concerned with is how well the engineered design is executed.

There are many engineering and design considerations. On the drawing board, I think the Leopard use of balsa core (higher sheer strength) throughout the hull is a great design with great use of materials for maximum strength to weight ratio in this price range, but in the long run I would not feel comfortable with this construction because of fears of water intrusion in the core. The Gunboat engineering is great but you pay for it. Best of all is the Boeing's epoxy carbon fiber composites built by RTM and cured in an autoclave which are used for the F-22 Raptor, but look at the cost of one of those!

[muskoka]

Originally Posted by CaptRehab

Absolutely correct. But I am assuming the hulls of all the catamarans from the major manufacturers are properly engineered. What I am concerned with is how well the engineered design is executed.

I think the actual design and manufacture of the hulls is a pretty consistent product. The weak points in virtually all production boats seems to be flaws in how well third party systems are installed and integrated. I think those areas are where the lowest bidder becomes the supplier. And where poor installation practices can become aggravating even if they're not necessarily dangerous.

A good example is our aircon system: There was an installation goof in that they were mounted slightly off level such that the condensate tray didn't properly drain which leaked water into the bilges. On top of which the aircon tray is galvanized steel and these trays tend to rot out. We replaced our tray with a fiberglass unit - but the question remains as to why something as expensive as a marine aircon can't be built in a more idiot proof manner?

Or sea strainers which are quite well made but so bloody obscure that you can't find a replacement mesh easily? (We did, but have to ask ourselves WTF as to why the boat didn't come with a list of vendors for all this stuff.) I've had the same conversation with owners of virtually every major brand of yacht.

There are many engineering and design considerations. On the drawing board, I think the Leopard use of balsa core (higher sheer strength) throughout the hull is a great design with great use of materials for maximum strength to weight ratio in this price range, but in the long run I would not feel comfortable with this construction because of fears of water intrusion in the core.

I have the same reservations. One acquaintance with a very well made boat had problems with the foam core because through hulls were installed without sealing the cored areas around them. If it had been balsa the moisture would've wicked further and perhaps been more difficult to resolve.

Another friend had water leaking from the light fixtures of his balsa cored bimini because the fasteners weren't gooped in. That's been fixed and it will dry out, albeit slowly. Nonetheless, it's a stupid 5 minute job that some installer forgot, or couldn't be bothered to do. In the meantime, he's dragging around a hundred pounds of unwanted rainwater in his bimini.

The Gunboat engineering is great but you pay for it. Best of all is the Boeing's epoxy carbon fiber composites built by RTM and cured in an autoclave which are used for the F-22 Raptor, but look at the cost of one of those!

F-22's are great going to weather, reaching and they tack beautifully. But the anchor locker is rubbish and there's no room to park an Eskie with cold beers.

[Dragon Lady]

Don't forget the problem with the wings trying to fall off the new Boeing 787!
All jokes aside most manufactures, especially French ones are going to be very tight with their technical data.They are trade secrets and take a lot of time and money to develop, the last thing they want is to give any of that away to a competitor.
As a buyer you need to look at the finished product, how it performs and the track record of the manufacturer and how they deal with problems.
Forget the sales spiel BS, look at what you are really going to use the boat for and talk to owners to see how happy they are living with the boat you think you want.
Also remember the very best engineers are right about 60 to70% with their theoretical development ideas and it takes time to evolve and perfect a design.
That's where I believe FP has the advantage over most of it's competitors.

[CaptRehab]

Originally Posted by Dragon Lady

Don't forget the problem with the wings trying to fall off the new Boeing 787!
All jokes aside most manufactures, especially French ones are going to be very tight with their technical data.They are trade secrets and take a lot of time and money to develop, the last thing they want is to give any of that away to a competitor.
As a buyer you need to look at the finished product, how it performs and the track record of the manufacturer and how they deal with problems.
Forget the sales spiel BS, look at what you are really going to use the boat for and talk to owners to see how happy they are living with the boat you think you want.
Also remember the very best engineers are right about 60 to70% with their theoretical development ideas and it takes time to evolve and perfect a design.
That's where I believe FP has the advantage over most of it's competitors.

I think you are right that they will share more information on the tour of the factory after I have given them a deposit. I have chartered a few Cats already and plan to charter more, including the Lipari. I find that a week aboard and sailing it in a variety of conditions reveals a lot. Also talking to the local captains working for the various charter companies over drinks at the bar has been an education. For example none of them seemed to like the rigging on the Leopards, and Lagoons perform best dockside. I don't recall them having anything to say one way or the other about Voyage catamarans.

[CaptRehab]

Originally Posted by muskoka

I think the actual design and manufacture of the hulls is a pretty consistent product. The weak points in virtually all production boats seems to be flaws in how well third party systems are installed and integrated. I think those areas are where the lowest bidder becomes the supplier. And where poor installation practices can become aggravating even if they're not necessarily dangerous.

I assume you are happy with the Lavezzi's performance. The Lipari seems to be a fair bit heavier for the same waterline which makes me wonder if I will still be happy with it. I appreciated the performance of a 10 year old Athena I chartered. I do like the ergonomics of the Lipari however. Thinking about when I'm a bit older it might be easier to navigate the cockpit and deck if I don't have to step up, down, over and under to move about the boat.

Loved the comment about the F-22 going to weather. LOL At Mach 2+ I would bet it would go to weather well. I wonder where you would put a radar reflector on it. I hear they are hard to see on radar.

[Cotemar]

Moderator's place keeper for Lipari 41 thread

[Dod42]

Anyone know how wide the rear beam is on a Lipari particually where the rear winch is mounted? We ordered ours without the bowsprit and Spri kit so there is no winch on the rear beam. I think what is fitted is a Harken 40.2ST for 42? I have been given a Harken 48.2ST but not sure if it is too big to fit. At this stage looking to use it to help lifting the dingy maybe an Asymetrical later. Otherwise I will have to look around for someone wanting to swap a 48 for a 42 in OZ?

[Takamoana]

Originally Posted by Dod42

Anyone know how wide the rear beam is on a Lipari particually where the rear winch is mounted? We ordered ours without the bowsprit and Spri kit so there is no winch on the rear beam. I think what is fitted is a Harken 40.2ST for 42? I have been given a Harken 48.2ST but not sure if it is too big to fit. At this stage looking to use it to help lifting the dingy maybe an Asymetrical later. Otherwise I will have to look around for someone wanting to swap a 48 for a 42 in OZ?

Hi Dod42
The beam is 180mm wide and our, factory fitted, winch is a 40st 2 speed. We have not needed the winch for the dinghy but the position is not ideal for the spi sheet as you cannot see the sail when using the winch. We use one of the genoa winches for the stbd sheet and only reluctantly use the aft winch. I have considered relocating the winch to the side deck but must admit it is way down my priority list - the spi hasn't had that much use lately. I also saw a Lipari that had fitted extra blocks and rub rail to lead the port sheet to the helm but not sure how effective this has been.
Cheers
Gary