Magic Merlin

The Daily Sail examines Fibrefusion's new Merlin Rocket featuring a canting, rotating rig and exotic construction

A must-see at London Boat Show is a radical new Merlin Rocket, centrepiece on the Harken stand, upstairs at 291E.

Scantily Clad, as the Merlin as has been dubbed, is unique in several way. She has carbon spars with a mast that both cants and is rotating, similar to that of a 60ft trimaran. Part of her is also built using a novel filament laminate technique.

The boat is the brainchild of Steve Neal, whose company Fibrefusion manufacturers composite bits and pieces in Penryn just outside Falmouth in Cornwall. These include carbon fibre panels with Nomex or foam core for yacht interiors and other custom products - currently they moulding some recumbent push bike seats. Aside from laminating they also make hitech PBO cordage.

The advantage of the filament build technique is obviously that it pars down weight to the absolute minimum. The structure is specified and then calculated using a finite element analysis programme that plots the path of the fibres. Software can then be used to test the resulting panel. The fibres can then be 'printed out' in an array of unidirectional tapes, bonded to a core - in the case of the Merlin, Corecell was used.



Scantily Clad has a wooden hull, centreplate case and transom as required under the Merlin Rocket class rules built by Lawrie Smart, but her main bulkhead and foredeck are made using the filament technique. Neal says that the wooden hull weighed 41.5kg while the deck, centreplate and mast support bulkhead came in at just 9kg.

While such a build technique is perhaps overkill in the Merlin class, Neal admits that he has no intention of sailing the boat, but has undertaken the project as a test bed. During the show he has been looking to sell the boat for £10,500.

Equally interesting is her Superspar rotating carbon fibre mast and rig which can be canted by up to 20degs each side simply by hauling in on the shrouds. Neal believes that this will alleviate the need for a spinnaker when reaching although there is the facility to launch a kite from either side when running. As on 60ft trimarans, canting the rig to weather should allow the boat to be sailed upright and present more of the sail plan to the wind. Rotating the mast should create a better airflow over the mainsail, improving pointing ability.

Showing the mast step and the mast rotation control lines. Harken muscle blocks are fitted to the forward and aft sides of the mast for mast pre-bend and jib halyard tension.



Another novel feature of the boat is her centreplate which has an elliptical trailing edge that Neal created from copying the tail fin of a whale.



The four lines led to port and starboard control - cunningham, rake, kicker and spinnaker uphaul/downhaul. With the canting rig Neal expects that the roles of the mainsheet and kicker will have to be reappraised.

Significant weight savings - Neal estimates around 30% - have also been made by the use of rigging and some control lines being made in the aramid PBO - made by Fibrefusion - while the main and jib sheets are in Spectra.

Neal is also proud of the beautifully crafted carbon fibre spreaders the boat has. These they made in pre-preg carbon and are structurally tapered with eight layers of carbon in one end and six in the outboard end. The spreaders are made from a combination of unidirectional and woven fibres and cooked at 120degC at 90psi. He estimates their weight to be 25% that of conventional aluminium spreaders. These can be bought separately with end caps for £80 inc VAT.

At present Scantily Clad still needs a rudder and it will be interesting to see if her developments work out on the water as well as in they do in theory.

For more information go to the Harken stand or contact: Fibrefusion tel: +44 1326 378787 Email: enquiries@fibrefusion.com