All things Class40

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huey 2

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AMHAS MOVES INTO THE LEAD IN A STORMY AZORES ARCHIPELAGO
The Anglo-American crew on AMHAS moved into the lead at the Azores gate to the west of the archipelago today at 19H19 UTC with a 51 milles lead over their closest rival, the Dutch team on SEC HAYAI. In this 8th and final leg of the GLOBE40, Craig Horsfield and Oliver Bond have covered nearly 2590 milles, with around 1270 milles to go to the finish in Lorient, Brittany. Like their fellow competitors, they’re having to contend with some particularly difficult conditions with a front rolling through generating 40 knots of SSW’ly wind, gusting to 55 and heavy seas with 6 to 7-metre waves. GRYPHON SOLO 2 posted up to 62 knots of wind last night. AMHAS is ahead of the latest forecasts and could well cross the final finish line in this round the world epic on Tuesday 14 March.
One final test before the finish

Having set sail from the southernmost island in the Antilles, Grenada, on 24 February, the fleet initially headed northwards, picking off all the islands of the Caribbean arc whose names conjure up a sense of gentle tranquillity: St Vincent and the Grenadines, Saint Lucia, Martinique and Dominica. WHISKEY JACK even extended her time there with an unscheduled stop in Guadeloupe on Sunday 26 February for a rapid repair to one of her rudders. Alas, the pit stop cost the crew dearly the following week, which was punctuated by a zone of high pressure that was impressive in scale and duration. Indeed, the extensive area of calms stretched from the Moroccan coast to the Bahamas, or up to 400-miles wide, and spanned a period of time reminiscent of a remake of the doldrums. Ensnared for days in zero or very light airs, the skippers had no other option than to sit tight and wait for the wind to kick back in. They were soon back with a vengeance though, because by hooking onto the southern edge of a low-pressure system located in the North Atlantic, they could finally climb up to the latitude of the Azores archipelago, albeit at the mercy of some meaty winter depressions. Conditions over the past 24 hours have really put the machines and the sailors to the test, with more of the same due to be served up over the next 24 hours. Having already clocked up over 30,000 miles since the start of the event last June, it’s all about striking a balance in the sprint for the finish.
A week to celebrate the string of arrivals in Lorient
Together with the teams from LORIENT GRAND LARGE and LORIENT AGGLOMERATION, the organisation is putting in place a comprehensive programme to round off the event in style with the focus on enabling the public to share what has been a truly unique round the world adventure, the prologue for which set sail from LORIENT LA BASE on 11 June 2022.
The programme step by step (local times):

  • On Saturday 11 March – 11:00 hrs: inauguration of ‘LE GRAND VOYAGE DE LA GLOBE40’ exhibition, 9 x 3.5 m high four-sided totems dockside in LORIENT LA BASE, which recount the great epic leg by leg
  • Tuesday 14 March – 10:00 hrs: press conference – Cité Eric Tabarly
  • Tuesday 14/ Wednesday 15 March: according to the ETA of the first competitor
  • Wednesday 15 March – Sunday 19 March: other arrivals
  • Sunday 19 March – screening of the 26’ film summarising the event – prize-giving – special evening – Cité Eric Tabarly
An overall ranking to be decided in Lorient
Though AMHAS seems to have a firm grip on the top spot in leg 8 with a lead of around 80 miles over Dutch rival SEC HAYAI (Frans Budel / Ysbrand Endt), the latter still has the potential to take the lead of the overall ranking as there were just 4 points separating the duos at the start of this coefficient 2 race. GRYPHON SOLO 2 meantime looks set to hang onto her 3rd place. After 9 months of racing and 8 legs, final victory will go right to the wire then. Meantime, penalised for stopping off in Guadeloupe, WHISKEY JACK is set back from the top 3, but she too could well make landfall in Lorient before the weekend of 18/19 March. Right now, whilst the main focus is on trying to avoid damage in the current gale, it’s still very much game on in this circumnavigation of the globe.


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huey 2

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The Globe40 sailboats return to Lorient after their world tour​

Lorient-La Base (Morbihan) is back in the colors of the Globe40, the race around the world whose prologue it hosted in June 2022. An exhibition is inaugurated this Saturday March 11, 2023 on the quays pending the return of the announced fleet by Thursday.

The Globe40 competitors left Lorient on June 11, 2022 for a double-handed loop around the world. They are expected from Thursday for the arrival. | JEAN-MARIE LIOT GLOBE40View full screen
West FranceOlivier CLERO .Published on03/10/2023 at 7:46 p.m.

OK
The Globe40 skippers are back in Lorient ( Morbihan ). Nine months after launching the prologue of this double-handed sailing race around the world , the offshore racing center will welcome the finish of the last leg.

The first are expected on Wednesday March 15, 2023 if the depression in the middle of the Atlantic does not cause them too much concern.

An exhibition on the quays​

In the meantime, on land, we are preparing to welcome them with an exhibition on the quays of the submarine base this Saturday, March 11.
The prize-giving is scheduled for Sunday March 19, if after more than eight months at sea and 30,000 miles covered, the five crews still in the race have returned safely.
 

huey 2

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pironiero

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Weight it's actually not an issue on class40s. There is a minimum weight and they could build them a lot lighter.
so hypothetically you could build a really light hull and stick additional weight to the keel? or keel weight is strictly determined as well?
 

Trocola

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so hypothetically you could build a really light hull and stick additional weight to the keel? or keel weight is strictly determined as well?
As RedFlag pointed out it's not longer easy to produce a below weight hull due to panel surface forward. Actually the first clak 40 sailed by Nicolas Destais was heavier than the minimum.

About adding weight to the keel. Class 40 limits righting moment, so d pending where you add weight to the keel RM could be increased over the limit. One class40 added small fishing sinkers to the top of the keel until they reached the minimum weight .
 

huey 2

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Infomercial from Seahorse Mag

Unstoppable forces​

Unstoppable forces

Visit Sicomin
While Class40 design moves forward apace parallel improvements in materials and build techniques are adding a further layer to the relentless improvements in sailing performance and reliability that we are seeing
When Aurélien Ducroz won the Class40 World Championships last summer, his victory against stiff competition in this intensely competitive fleet was a strong endorsement of his own skills and talent, but also a validation of Crosscall, his radical and remarkable new boat. Kudos is due to the Marc Lombard design office, whose new Lift V2 design exploits the class’s 2020 rule change to the full. Crosscall’s builder, Grand Largue Composites (GLC), also deserves credit for delivering a boat that didn’t just meet its design weight target but surpassed it, coming out of the moulds lighter than even the design team had expected. And that’s another feather in the cap for Sicomin, which supplied nearly all the materials.
The boat turned out to be faster than Lombard’s VPP had calculated, as GLC’s managing director Xavier Gosselin explains, and since Crosscall’s launch at the end of 2021 it has become clear that the CFD modelling for the Lift V2 design was run at less than its actual top speed. It has also proved to be an excellent performer in light airs, with Ducroz overtaking most of his rivals after poor starts in two of the World Championship races, staged on an often almost windless Bay of Biscay. But while the boat is showing itself to be a good all-rounder it is conceived and optimised for a specific purpose: winning the Route du Rhum. The Lift V2 is a development of Lombard’s Lift 40 design which Yoann Richomme sailed to victory in the last edition of the race in 2018, crossing the Atlantic from St-Malo to Guadeloupe in 16 days and three hours – eight hours ahead of his closest rival – and establishing a new class record. Crosscall is reckoned to be capable of shaving another day off that record, given similar weather. For context, that’s faster than most of the older generation of Imoca 60s.
Whilst the new Richomme boat was built by Lalou Multi, Ducroz’s was built by GLC in Caen, Normandy and Gosselin was involved in the composite manufacturing design loop for the Lift V2, working closely with Lombard’s team, before he started building it. A small, independent custom boatbuilder and manufacturer of high-end composite parts, GLC has built Ocean Fifty multihulls and a seaplane as well as five Class40s, high-performance dinghies and the XO range of small cruising and racing keelboats, plus a range of non-marine projects. Over the last 15 years GLC has earned an enviable reputation for the quality of its vacuum-infused epoxy composite hulls, parts and structures. Since the establishment of the company, Sicomin has been its sole supplier of epoxy resins for infusion, hand lamination and adhesion and has also supplied fibres, core materials and more. ‘We have been using their products since the beginning, we have never had a problem and I would not want to risk trying a different supplier,’ Gosselin says.
Main picture: the current world champion Class40 Crosscall is lighter than its design weight and faster than predicted by Marc Lombard’s VPP. Credit is due to the builder Grand Largue Composites and Sicomin who supplied nearly all the materials
Crosscall is also notable for being the first Class40 partially built with natural flax fibre. Ducroz was very keen to use the maximum of flax in the build, Gosselin says, but Lombard – who had to certify and warranty the structure of the boat in ocean racing use – was more cautious. A compromise was reached; the cockpit was designed to be effectively non-structural with the mainsheet loads supported separately. This allowed the cockpit to be built with a hybrid biaxial fibre that has 50 per cent flax content, which Sicomin had produced specifically for this project. Other elements that incorporate flax fibre include the tunnel, the engine cover, the ballast tanks and the cap. The rest of the boat is reinforced with 100 per cent glassfibre.
Given the enormous stress loads that a Class40 hull must withstand, the extreme danger of any structural failure in mid-ocean and the need to make these boats as lightweight as possible, using even that amount of a relatively unproven material like flax is quite a bold move. That said, the use of flax is an easier choice to make in Class40, where carbon fibre is banned in hull construction to stop costs from spiralling out of control, than in the full-carbon Imoca 60 class where even the most eco-conscious teams have found that using flax for anything more than peripherals like hatch covers and internal parts will have a negative impact on performance.
The fact that Crosscall came out of GLC’s shed weighing less than its design displacement is remarkable, given that flax can easily absorb a lot more resin than glassfibre does unless the infusion process is carefully and skillfully controlled. ‘If we compare the materials flax is twice as light as glass but only half as strong,’ Gosselin says. With the right infusion technique a flax fibre hull can be the same weight as a glassfibre hull and very nearly as stiff, he explains, but its lower strength limits its use in an ocean racing hull that needs to be fully optimised for light weight and high performance. ‘For a non-racing boat with lower performance flax is OK,’ he says. 'But it’s more expensive today and the cost can be a big problem.’ At this early stage of its adoption, flax is also more timeconsuming for boatbuilders because, like any new material, they don’t have the familiarity and long experience of using it.
Crosscall’s construction is exactly the same as any comparable boat built in all glassfibre, Gosselin says. Epoxy resin is used throughout as it’s stronger and lighter than polyester or vinylester, and all parts are made with a high-density closed cell PVC foam core. Four different types of glassfibre are used as well as the flax fibre. All of the fibres and foam, as well as the resins, are Sicomin products.
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Above and below: a hybrid biaxial fibre with a 50 per cent flax content was created for Crosscall’s cockpit, ballast tanks and other non-structural parts. Internal structures are laminated into the hull with Sicomin SR 8200 before the hull and deck are bonded with Sicomin’s Isobond SR 7100 which has a very high fatigue strength and excellent resistance against micro crack propagation
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The hull was moulded and infused in one piece and the deck – including the cockpit – was also infused as a single part. The internal structure was then laminated into the hull by hand before the hull and deck were finally bonded together. Epoxy bonding primer makes demoulding easier and also serves as an undercoat in the polyurethane exterior paint system, which is used instead of gelcoat to protect the epoxy hull from UV damage.
The main infusion resin selected for Crosscall’s construction is Sicomin’s SR 1710. This is a highmodulus structural epoxy system with extremely high performance. Designed specifically for infusion and injection, it has very low viscosity and its low-reactivity hardener makes it suitable for large part manufacturing. SR 1710 has excellent mechanical properties, especially its inter-laminar sheer strength and it retains those properties in a wet environment, so it’s ideal for the hull of a highperformance ocean racing yacht.
Sicomin’s SR 8200 was used to laminate the internal structures to the skin of the hull. Ideal for hand laminating, this system includes a choice of hardeners with a wide range of reactivity, which makes it equally suitable for making large or small parts. Its three main advantages for boatbuilding are low toxicity, extremely strong mechanical properties and relatively low cost. ‘During application the low level of odour and fumes is remarkable,’ says Tom Kerriou, Sicomin’s project manager for the Crosscall build. ‘Because the maximum temperature resistance is at least 90°C, the parts need to be post cured to enable them to work at a service temperature of 60 to 70°C.’
The hull and deck are joined together with Sicomin’s Isobond SR 7100. This high-performance adhesive epoxy is specifically designed for composite structural bonding and – crucially for the hull of an ocean racing yacht – it has very high fatigue strength and excellent resistance against the propagation of micro cracks. Thanks to its gel texture it is easy to apply even on vertical surfaces and three variable speed hardeners are available.
Another product that played a very useful role in this build is the epoxy bonding primer, Undercoat EP 215 HB+ supplied by Sicomin’s sister company, Map Yachting. ‘We have been using it for six years and we don’t make any parts without it,’ Gosselin says. ‘It is a good interface between the composite part and the hull paint, it’s easier to demould, it gives a surface with low porosity and it’s very easy to sand, much easier than resin.’ It’s normally used as a very thin film but a thicker coat can be applied if there is more porosity on the surface.
Since the launch of Crosscall GLC has started building a second Lift V2 Class40 and a third one is planned. ‘The hull and deck will be exactly the same but we are making some modifications to the internal structures,’ Gosselin says. ‘We have moved the mast step aft by 10cm and the keel is slightly modified.’ The weight distribution will be subtly changed to account for the Lift V2’s higher-than-expected boatspeed, with more weight carried further aft to keep the bow trimmed up when power reaching in big waves.
‘The second boat is all glassfibre because the sailor didn’t want the complication and expense of flax,’ Gosselin says. ‘But for the next one we’re talking about flax again.’
Click here for more information on Sicomin »


 
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