Volvo Ocean Race- Southern Spars rise to the Volvo Challenge

by Richard Gladwell/Sail-World.com NZL on 14 Mar 2015 With a quarter of a century of involvement in Round the World racing, it was an obvious move for Volvo Ocean Race organisers to go to Southern Spars for the one design, supplied Volvo 65 class.

The Auckland based, UK owned spar manufacturer’s involvement in the Round the World Race extends back to 1989 with Sir Peter Blake’s Steinlager II, which won all six legs of the race – a feat which has never been repeated.

Ten rigs were required for the seven Volvo 65’s to be sailed in the next two editions of the Round the World classic.

The new style Volvo Ocean Race involved the construction of one design hulls, rigs and sails for the supplied yachts. The Volvo 65 rigs run a full ECsix package – backstays as well as side rigging.

That move is geared towards cost reduction and making the fleet more robust. It is a change which has so far paid a big dividend, with all boats finishing each leg, except for the grounding of Team Vestas Wind.

The new Volvo Ocean Race has also been marked by close racing, with all six of the six boat fleet finishing within six hours in Auckland.

Contrast that with the last race, where competitors were responsible for providing their own boats, only three of the fleet finished Leg 1 on their own bottoms. There were two dismastings and boat damage became the hallmark of that race.

But significantly in the last Volvo the only two boats equipped with Southern Spars and ECsix rigging were the only two competitors that did not suffer mast or rigging failure.

Against that backdrop it was an ambitious call to require a boat and rig that would not break, and would be raced in this race, as well as the next edition.

As well as being kings of the world of custom build spars, Southern also have the one-design carbon spar experience to draw on from the Olympic classes, where they are the sole supplier of carbon rigs in three classes.

'This is the first time that any one manufacturer has supplied a full one design carbon rig package for a fleet of boats to race around the world' says Marketing Manager, Josh Impey.

To create the new Volvo65 rig, Southern Spars designers get the sail plan and the boats righting moment from the Farr office, who were commissioned to design the new class.

Rig load calculations are not just done by Southern Spars. The three parties involved in the Volvo 65, Southern, Norths and the Farr Yacht Design office.

From there a mix of technology, history and experience is combined to produce the design and specifications for the rig.

Working closely with the sail designer the mast bend is matched to sail shape and sail loads are cross-checked with the locks and fittings.

Southern’s designers review their historical data to see if current design components such as locks can be used to meet the loads or if new fittings are required.

A feature of the masts and booms is to have locks for the mainsail at full hoist and reef points, as well as locks in the boom at each reef.

Once these are fitted, the locks cannot be easily be moved and Southern work closely with North Sails to ensure the reef heights and girth measurements are carried over into the spar design.

Southern Spars and North Sails are owned by the same parent company, North Technology.

'With Norths and Southern Spars the two computer design programs (Membrane and RigCalc) talk directly to each other' explains Impey. 'The Norths sail design coordinator talks directly with our construction engineer, even though they may be located in different countries'

The two rig and design packages have been developed over the years and are now so accurately aligned that the masts can be set up and tuned from the first day. Very little rig adjustment is required after the initial rig tune.

One of the criticisms of any attempt at one design race manufacture is that there will always be small differences in manufacturing which will give an advantage in strength or performance.

Southern Spars have gone to extreme lengths to ensure the complete uniformity.

For the Volvo 65 project Southern established a production process to ensure one design uniformity. Drilling jigs are used for the masts booms and spreaders and each is identical to others in the batch.

New moulds were made for the Volvo 65 masts, booms and spreaders. The moulds all have incorporated datum marks to further ensure that all spars are identical and assembly variances are eliminated completely.

When the masts booms or spreaders are removed from the moulds, the datum marks are visible on the section. The spar sections are placed in jigs, the datum marks are aligned and checked before any drilling starts.

Using this method, each mast is identical to its predecessor.

Every mast is subject to a bend test before leaving Southern Spars Avondale factory – the variance is a couple of millimeters

As a further check all components in the mast are also weighed, and logged in the computer to ensure the specified weight targets are being met.

The Volvo 65 masts are built in two pieces which allows Southern to laminate internal tangs, spreader compression tubes as well as install carbon boxes for the lock cassettes and headstay tangs, making sure these parts are correctly supported and attached to the mast wall.

Before the mast section is joined Southern also run mouse lines for all the trip lines, halyards and wiring and make sure there is no chafe points inside the mast.

Southern have simplified the rig by including deflectors in the mast – the end result is that only two sets of after stays are needed to support the mast. One stay does two functions.

One of the challenges with the VO65 mast was the fact that it is deck stepped and the vertical tongue on which the mast sits had to be carefully designed and engineered to allow deflector lines, hydraulics and all the electrical cables to run through the tongue and mast base.

Booms on the Volvo 65 will be similar to what the Volvo 70’s used in the last edition of the Volvo Ocean Race. Rotating goosenecks are used again, which helps reefing.

Reaching struts are being used for the first time in the Volvo Ocean Race, requiring Southern to draw on their experience in the Open 60 class, which also use the struts.

All the standing rigging on the Volvo 65 is an ECsix package.

Another innovation is to use low stroke turnbuckles which are shorter than standard turnbuckles used to connect the stays to the hull. Low strokes rely on getting the rigging length perfect and are a weight-saving measure.

The ECsix rigging was made in Sri Lanka and the metal fittings are made at PML (a Southern Spars company) on Auckland’s North Shore.

The Volvo 65 hulls were built at three facilities in Europe, and assembled at a fourth, Green marine in Southampton.

The masts were freighted from New Zealand to Green Marine where the rigging was attached and the masts stepped and tuned as each completed boat was accepted by a Volvo Ocean Race team.

Now with four legs completed and almost at the halfway point of the race, the rigs have been pulled from the boats for a major service and check.

Only one rig has been returned to the factory for repairs to the sail track, with the other five requiring expected maintenance. The new rig for Team Vestas Wind has been built and is ready to leave the Southern Spars facility in Rosebank Road, West Auckland.

The return to factory for a proper repair was caused by the crew of Dongfeng just pushing the loads to the absolute limit, carrying a big Code Zero sail further up the wind range and creating issues with the mainsail track.

Now all are back on the water, and along with the boats, are good for another one and a half laps of the planet.



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