Carbon masts

Rondal built its first carbon mast in 1996 – a 60-metre one-piece construction that defied industry conventions, not only because a one-piece mast of that size had never before been attempted but because Rondal also chose to invent its own design and construction process.

Working closely with the Dutch aerospace industry and Gurit/SP, Rondal set aside existing industry methods in favour of:

  • An 810m2 composite building hall, itself an oven capable of curing at up to 90°C
  • A prepreg and resin system jointly developed between Rondal and Gurit/SP - now the industry standard for vacuum-bagged curing
  • Full-length fore and aft inner mast shells to carry halyard systems, cabling and vents, in addition to local reinforcements for high-loaded areas
  • A vacuum-bagged mast lamination system incorporating two or three curing stages (depending on size) at increasing temperatures to ensure even resin flows, as well as 100% vacuum efficiency.
  • Mast shells and laminates constructed, vacuum-bagged and cured within the same frames, without any need to move them.

The benefits include the integrity of a one-piece mast with no interruption to longitudinal fibres, minimal void content and no constraints on achieving optimum bend characteristics; assured mast straightness; mast taper options; no limitations on section shape; reliable weight prediction; and very high quality assurance supported by fully independent testing.

Rondal’s experience-and-information-rich relationships with leading sail makers and rigging suppliers ensure the perfect optimisation for every project.

Two major new developments from Rondal Spars:

Style-to-order service

Rondal spars can now be individually styled – in overall shape, section, fairings and finish – to suit the design preferences of the owner, architect and stylist. Every Rondal mast is built on a new mould, so the flexibility to meet styling as well as performance objectives is inherent in the process.

Unlimited length

While 73m is the maximum length for one-piece Rondal seamless masts, Rondal technology is now applying the same seamless construction process to masts of any specified length, without restriction. Consult our experts about your large projects and the advantages that Rondal composite mast technology can bring.

Exceptional service levels are delivered by Rondal experts during the design and build, just as owners and crew can be sure of full after-sales support whenever and wherever required in the future.


Constructed from composite, Rondal spreaders are designed and manufactured in all shapes and sizes and can incorporate mountings for all types of equipment as well as connection systems appropriate to the mast and rigging specifications.