Another Broken Lagoon

[goeasy123]

Another broken Lagoon... a 410 this time

Another Broken Lagoon

Does anybody else think the skinny shear web under variable compressive and tensile loads is a bad idea or is it just me?

 

[Yngmar]

Nothing a couple barrels of resin and rolls of glassfibre can't fix! ?

 

[SlowlyButSurely]

No, not just you. I saw one blown onto rocks in Spain a few years ago. It literally disintegrated. Studying the wreckage I could see that it appeared to be built from old scraps of balsa covered with a paper thin layer of grp. The only part that was solid grp was the cockpit which had many areas where the fibres had not been properly impregnated with resin. The interior furniture appeared to be made from some inferior plywood held together with self tapping screws.

I'm sure they are great if nothing ever goes wrong but not for me.

 

[goeasy123]

A fishing boat hit my Najad last night. It's gonna cost me a least a fiver in T Cut.

 

[BurnitBlue]

I'm sure they are great if nothing ever goes wrong but not for me.

I look at this from a different angle. I sailed a Prout Catamaran on both sides of the Atlantic and Med for 5 or six years consecutive. Very few "happenings" are the cause of something going wrong. There is nothing wrong with a gale, a Squall, or the anchor dragging etc. They are perfectly normal and are happening somewhere else right now. The chance of an anchor dragging are quite high and it is not as if an underwater digger buried the anchor then filled the hole with rocks and cement. It is perfectly normal for an anchor to drag. Nothing actually went wrong. Anchoring is always a lottery.

Also, nothing is wrong when an ocean going yacht meets a storm.

What did go wrong happened on the architects drawing board long before the catamaran (for instance) met the water. Lack of supervision of the boat yard and the materials used contributes as well.

Prouts were built with both hulls intergral from stem to stern. I shudder when I see a catamaran with a trampoline. A catamaran is basically two hulls although close together, are actually in a differen part of the ocean. One hull goes up on a rising wave, the other hull drops on a falling wave. The twisting and torsion are constant hour on hour day by day. A trimaran sailor once told me that one hull was always doing something different from the other two. He wore musical ear defenders to block out the constant creaks when on passage.

To build a three story boat out of kitchen materials to a concept based solely on comfort is an insult to the sea and a gamblers optimism that the house rules do not apply to them.

I am not exlaining myself very well. To cut to the chase, i believe a boat should be designed and built for the sea and whatever normal situation that boat could find itself in. If the conditions exceed the design brief based on costs then a well designed and built boat will still give the crew a fighting chance.

Anyway, I am being a bit daft trying to summarise a complex subject that would need a whole book to explore properly.

 

[Just_sayin']

Support

Lagoon Catamaran: sale, rental, catamaran and luxurious yacht construction

 

[greeny]

Reading through the links it looks as though they are supporting the owners who can show "normal" use of their boats. Whatever that is.
Then they will support the repair process. After the repair they will issue the owner with a warrantee it seems. FOR ONE YEAR! Wow they've got a lot of faith in their repair process. Just my thoughts.

 

[geem]

I look at this from a different angle. I sailed a Prout Catamaran on both sides of the Atlantic and Med for 5 or six years consecutive. Very few "happenings" are the cause of something going wrong. There is nothing wrong with a gale, a Squall, or the anchor dragging etc. They are perfectly normal and are happening somewhere else right now. The chance of an anchor dragging are quite high and it is not as if an underwater digger buried the anchor then filled the hole with rocks and cement. It is perfectly normal for an anchor to drag. Nothing actually went wrong. Anchoring is always a lottery.

Also, nothing is wrong when an ocean going yacht meets a storm.

What did go wrong happened on the architects drawing board long before the catamaran (for instance) met the water. Lack of supervision of the boat yard and the materials used contributes as well.

Prouts were built with both hulls intergral from stem to stern. I shudder when I see a catamaran with a trampoline. A catamaran is basically two hulls although close together, are actually in a differen part of the ocean. One hull goes up on a rising wave, the other hull drops on a falling wave. The twisting and torsion are constant hour on hour day by day. A trimaran sailor once told me that one hull was always doing something different from the other two. He wore musical ear defenders to block out the constant creaks when on passage.

To build a three story boat out of kitchen materials to a concept based solely on comfort is an insult to the sea and a gamblers optimism that the house rules do not apply to them.

I am not exlaining myself very well. To cut to the chase, i believe a boat should be designed and built for the sea and whatever normal situation that boat could find itself in. If the conditions exceed the design brief based on costs then a well designed and built boat will still give the crew a fighting chance.

Anyway, I am being a bit daft trying to summarise a complex subject that would need a whole book to explore properly.

You could have just said they are a pile of junk?

 

[Rappey]

Parley revival first highlighted the lagoon problem. The worrying part was when he squeezed under the cockpit sole and discovered a full width bulkhead was not even sat in the line of adhesive.

 

[BurnitBlue]

You could have just said they are a pile of junk?

I was feeling chatty. I realised after a while that I had run ahead of my knowledge about yacht design and an architects brief. So I bailed out.

 

[stephen_h]

I look at this from a different angle. I sailed a Prout Catamaran on both sides of the Atlantic and Med for 5 or six years consecutive. Very few "happenings" are the cause of something going wrong. There is nothing wrong with a gale, a Squall, or the anchor dragging etc. They are perfectly normal and are happening somewhere else right now. The chance of an anchor dragging are quite high and it is not as if an underwater digger buried the anchor then filled the hole with rocks and cement. It is perfectly normal for an anchor to drag. Nothing actually went wrong. Anchoring is always a lottery.

Also, nothing is wrong when an ocean going yacht meets a storm.

What did go wrong happened on the architects drawing board long before the catamaran (for instance) met the water. Lack of supervision of the boat yard and the materials used contributes as well.

Prouts were built with both hulls intergral from stem to stern. I shudder when I see a catamaran with a trampoline. A catamaran is basically two hulls although close together, are actually in a differen part of the ocean. One hull goes up on a rising wave, the other hull drops on a falling wave. The twisting and torsion are constant hour on hour day by day. A trimaran sailor once told me that one hull was always doing something different from the other two. He wore musical ear defenders to block out the constant creaks when on passage.

To build a three story boat out of kitchen materials to a concept based solely on comfort is an insult to the sea and a gamblers optimism that the house rules do not apply to them.

I am not exlaining myself very well. To cut to the chase, i believe a boat should be designed and built for the sea and whatever normal situation that boat could find itself in. If the conditions exceed the design brief based on costs then a well designed and built boat will still give the crew a fighting chance.

Anyway, I am being a bit daft trying to summarise a complex subject that would need a whole book to explore properly.

I shudder when I see a catamaran withOUT a trampoline

 

[geem]

I shudder when I see a catamaran withOUT a trampoline

I think a trampoline is an extremely poor indicator of build quality. Having owned a Product Snowgoose 37 pre Elite model my take on this is different. Our Prout was light by normal standards and we kept it light. We carried very little in the way of gear. The central nacelle wasn't in the water. It had 2inch clearance. Lots of foam core used where normally they use plywood.
We always see them way over loaded. Weight is the killer of catamarans. It kills performance and an overloaded one will increase the risk of structural failure. The Prout slammed like crazy going to weather. It was disconcerting but they are strong so they can take the punishment. Modern charter cats that resemble a wedding cake with all those layers are built out of solid glass and ply. Hardly exotic materials. Our Prout was also built like that in 1980. If you want high performance in a cat it takes a lot of money. Cored hulls, vacuum infusion, carbon mast, carbon daggerboards. It all adds up but you get a high performance stiff and strong boat. Not something remotely like a Lagoon.

 

[BurnitBlue]

I think a trampoline is an extremely poor indicator of build quality. Having owned a Product Snowgoose 37 pre Elite model my take on this is different. Our Prout was light by normal standards and we kept it light. We carried very little in the way of gear. The central nacelle wasn't in the water. It had 2inch clearance. Lots of foam core used where normally they use plywood.
We always see them way over loaded. Weight is the killer of catamarans. It kills performance and an overloaded one will increase the risk of structural failure. The Prout slammed like crazy going to weather. It was disconcerting but they are strong so they can take the punishment. Modern charter cats that resemble a wedding cake with all those layers are built out of solid glass and ply. Hardly exotic materials. Our Prout was also built like that in 1980. If you want high performance in a cat it takes a lot of money. Cored hulls, vacuum infusion, carbon mast, carbon daggerboards. It all adds up but you get a high performance stiff and strong boat. Not something remotely like a Lagoon.

Popcorn time. To effectively strengthen the bows of a catamaran with a trampoline the force of the waves trying to seperate the hulls are in competition with the foresail trying to bring them together. Using a straight tube is weak and bendy. I believe the catamaran designer must borrow from the suspension bridge. I don't pretend to know the engineering but a quick look at some bow structures with complex inverted VEE's is their attempt to keep the bows the same distance apart. Prout got it right IMO.

Also, the idea of being bounced in the air on a squishy trampoline while the whole boat zooms underneath me at speed really does make me shudder. I have never sailed a Catamaran with a trampoline but my imagination would make me want to install a safety net across the transom to catch me. OK, my imagination can run wild so a joke with some truth perhaps.

 

[geem]

Popcorn time. To effectively strengthen the bows of a catamaran with a trampoline the force of the waves trying to seperate the hulls are in competition with the foresail trying to bring them together. Using a straight tube is weak and bendy. I believe the catamaran designer must borrow from the suspension bridge. I don't pretend to know the engineering but a quick look at some bow structures with complex inverted VEE's is their attempt to keep the bows the same distance apart. Prout got it right IMO.

Also, the idea of being bounced in the air on a squishy trampoline while the whole boat zooms underneath me at speed really does make me shudder. I have never sailed a Catamaran with a trampoline but my imagination would make me want to install a safety net across the transom to catch me. OK, my imagination can run wild so a joke with some truth perhaps.

A well designed cat will go to windward fast and efficiently. The trampoline allows a breaking sea to go through the trampoline with no structural impact. The same cannot be said of the solid bridge deck on a Prout.
Are you assuming that the beam design is insufficient on trampoline cats or just Lagoons? Maybe you could show us evidence of this causing structural failure?
My understanding of catamaran structural failure is that they break bulkheads. Nothing to do with front beam failure.
Prouts structural resilience comes from the fact that they are small and heavily built. They are not a great example of how to build as they simply do not scale up. A 50ft scaled up Snowgoose would be a hideous tank of a thing pretty much like a Lagoon since they use the same basic materials of construction

 

[BurnitBlue]

A well designed cat will go to windward fast and efficiently. The trampoline allows a breaking sea to go through the trampoline with no structural impact. The same cannot be said of the solid bridge deck on a Prout.
Are you assuming that the beam design is insufficient on trampoline cats or just Lagoons? Maybe you could show us evidence of this causing structural failure?
My understanding of catamaran structural failure is that they break bulkheads. Nothing to do with front beam failure.
Prouts structural resilience comes from the fact that they are small and heavily built. They are not a great example of how to build as they simply do not scale up. A 50ft scaled up Snowgoose would be a hideous tank of a thing pretty much like a Lagoon since they use the same basic materials of construction

Read the thread by T21 when his bow structure suspension bridge thingy on one of his catamarans fractured. It does happen. Your opening words say it all. "A well designed cat will .... No argument from me about a well desgned cat. How many people can identify a well designed cat. Why do bulkheads break on a cat yet rarely on a monohull? Could it be the twisting and bending that a trampoline does nothing to mitigate. A Prout gets away with it because they have quite a narrow beam.

Your argument that a solid bow structure does not scale well because it will look ugly is not serious. Who the heck cares as long as the structure will last more than two years. If they are unable to achieve that then buy a monohull like (maybe) 99% of the maritime vessels, including commercial and military. The real problem with solid bows is windage not waves. Get hurricane winds under the bridge deck and over she goes. Saw that happen to a Snowgoose 37 in Vlicho bay while at anchor.

IMO catamarans have very severe design limitations with very narrow windows of safe usage. Go outside those limitations and watch out.

Anyway this discussion is fun but ultimately will descend into a nit-picking argument about safety, speed, load carrying, ascetics etc. Nit-pick away and take all the disadvantages of a catamaran out of the design and guess what you end up with? A monohull.

 

[EugeneR]

Reading through the links it looks as though they are supporting the owners who can show "normal" use of their boats. Whatever that is.
Then they will support the repair process. After the repair they will issue the owner with a warrantee it seems. FOR ONE YEAR! Wow they've got a lot of faith in their repair process. Just my thoughts.

We are looking for a catamaran to go world cruising in, and we have looked at the new Lagoons and have been told the 450 problems are fixed, but if Lagoon in any way suggests this 410's use is not "normal"... well they are off the list...

 

[Blueboatman]

I am suffering buyers remorse without even buying one .
Burn it blue
Quote: “To build a three story boat out of kitchen materials to a concept based solely on comfort is an insult to the sea and a gamblers optimism that the house rules do not apply to them.”

If you did decide to write a book on the subject, this would be a fantastic opening .

 

[Supertramp]

Boats come in many shapes and sizes designed for a very wide range of conditions such as lakes vs sea and charter vs ocean voyaging. The design brief and construction in modern times will differ a lot between intended uses. Older designs had less sophisticated construction often in heavier materials. Hence you can see tidy, solid, old Prouts that have circumnavigated, and the same with monohulls. While many of us will recognize ocean worthiness in a design, few models come with that label, they tend to earn it.

For catamarans especially, the forces involved make it hard to have a totally rigid structure and the designing in of flex to take out shock loadings is important. Same applies to monohulls - look at all the stiffening and transmitting systems used today. Lagoon appear to me to have designed a boat that doesn't deal with the continuous and shock loads met in ocean cruising (or even hard chartering?). No doubt you can cruise one long term but it would need careful judgement, restraint and probably luck to keep it safe. OK as long as you are aware of the limitations.

I'm not sure I would want that restriction even on my routine coastal sailing!

 

[BurnitBlue]

I am suffering buyers remorse without even buying one .

I think yours is better.

 

[geem]

Read the thread by T21 when his bow structure suspension bridge thingy on one of his catamarans fractured. It does happen. Your opening words say it all. "A well designed cat will .... No argument from me about a well desgned cat. How many people can identify a well designed cat. Why do bulkheads break on a cat yet rarely on a monohull? Could it be the twisting and bending that a trampoline does nothing to mitigate. A Prout gets away with it because they have quite a narrow beam.

Your argument that a solid bow structure does not scale well because it will look ugly is not serious. Who the heck cares as long as the structure will last more than two years. If they are unable to achieve that then buy a monohull like (maybe) 99% of the maritime vessels, including commercial and military. The real problem with solid bows is windage not waves. Get hurricane winds under the bridge deck and over she goes. Saw that happen to a Snowgoose 37 in Vlicho bay while at anchor.

IMO catamarans have very severe design limitations with very narrow windows of safe usage. Go outside those limitations and watch out.

Anyway this discussion is fun but ultimately will descend into a nit-picking argument about safety, speed, load carrying, ascetics etc. Nit-pick away and take all the disadvantages of a catamaran out of the design and guess what you end up with? A monohull.

Since you think that all catamarans have severe design limitations and a narrow window of usage, would you care to elaborate?
It would be interesting to take your view on how a 26t Lagoon 52 compares to a full Carbon Gunboat or maybe a Balance cat. Especially since all three are radically different. Lumping all catamarans together is like saying An Imoca 60 is just like a Hurley 22