Single-Piece Monolithic Carbon Masts
Maxspar manufactures carbon fibre masts as monolithic structures — in a single piece both in section and along the full length — up to 70 metres, for offshore racing yachts and superyachts. Our autoclave, among the largest in Europe dedicated to the production of nautical spars, operates at 6 bar and 120°C on sections up to 1,200×600 mm, enabling the production of masts exceeding 6,000 kg — a scale that very few manufacturers in the world are able to reach.
Working at this scale means confronting one of the most demanding engineering challenges in the industry: extracting the aluminium mandrel from profiles of such extraordinary size at the end of the curing cycle. With more than thirty years of production behind us, we have developed proprietary techniques that solve this problem with precision and repeatability, delivering truly monolithic structures without any compromise on dimensional tolerance or structural integrity.
The lamination uses pre-impregnated carbon from leading suppliers — Gurit, Deltapreg and CIT — wrapped manually around the male mould to obtain a single-piece, jointless, hand-tapered mast, with maximum fibre compaction, cured at constant and controlled temperature and pressure.
Superior Performance
The autoclave process guarantees optimal fibre compaction and eliminates voids and porosity in the laminate. The result is a lighter, stiffer and more reliable mast — engineered to withstand the most extreme conditions of offshore racing and ocean passages.
Why Autoclave Curing?
Our product is laminated on a male mould, compacted and cured in a pressure chamber at 6 bar plus the depression of the vacuum bag. This technology — derived from the aerospace industry — guarantees a finished product of maximum lightness and elevated mechanical characteristics, fully exploiting the properties of the carbon fibre.
The construction of carbon components in an autoclave is considered superior to any other manufacturing technique: laminates remain more compact, the possibility of air bubbles within the laminate is drastically reduced, and the Tg (glass transition temperature) reached during the curing cycle is maximised.
One-Piece Technology
A mast without lateral joins eliminates any risk of delamination at bonded interfaces under load — a decisive advantage in offshore racing and ocean passages. The unidirectional 0° layer runs continuously along the full length of the mandrel, allowing the fibres to work in complete homogeneity. The bending profile follows a smooth, uninterrupted arc: no stiffness steps, no weak points, no geometric discontinuities.
The rigidity of our masts is not only measurable on a data sheet — it is immediately visible in the yard. When the mast is lifted horizontally by crane before stepping, the difference compared to other manufacturers is apparent to the naked eye: our mast barely deflects under its own weight. For any experienced owner or rigger, this is the most direct and convincing proof of what our construction delivers.
Throughout the lamination process we record the weight of the piece at every step of the layup sequence. This is not a routine quality check: it is the method by which we guarantee that the finished mast corresponds precisely to the theoretical design, gram by gram and millimetre by millimetre. When we deliver a mast, the owner receives exactly what was calculated and promised. No surprises, no approximations.
Materials
Depending on the required performance and the vessel's intended programme, we work with three types of pre-impregnated carbon:
SE 84LV — T300
Unidirectional pre-preg in T300 fibre (240 GPa) — an excellent stiffness-to-weight ratio for cruiser-racers, circuit regatta and high-performance cruising yachts.
SE 84HT — T700
Diagonal pre-preg in T700 fibre — our benchmark material for the most demanding applications: offshore racing, ORC, IRC and superyacht racing. The optimal balance between performance and durability.
High Modulus — up to 380 GPa
Ultra high-modulus fibres — the same class of material used in Formula 1 and the aerospace industry. For those who demand the absolute maximum: maxi-yacht racing, Volvo Ocean Race, IMOCA 60, A-class superyachts. Every project is bespoke around the owner's specific requirements.
Standard Profiles
Standard available profiles (section in mm) with moment of inertia values where measured. Maximum section achievable: 1200×600 mm.
| Dimensions (mm) | Notes | kg/m | Iyy | Ixx |
|---|---|---|---|---|
| 106 × 72 | — | — | — | — |
| 116 × 78 | — | — | — | — |
| 126 × 80 | — | — | — | — |
| 140 × 90 | — | 2.1 | 220 | 82 |
| 148 × 93 | — | — | — | — |
| 160 × 100 | — | 2.8 | 360 | 130 |
| 164 × 101 | — | — | — | — |
| 170 × 105 | — | — | — | — |
| 180 × 102 | — | — | — | — |
| 180 × 110 | — | 3.4 | 540 | 190 |
| 190 × 112 | — | — | — | — |
| 200 × 110 | — | — | — | — |
| 205 × 98 | — | — | — | — |
| 210 × 120 | — | — | — | — |
| 210 × 130 | — | 4.5 | 870 | 310 |
| 215 × 130 | — | — | — | — |
| 240 × 120 | — | — | — | — |
| 240 × 150 | — | 5.8 | 1380 | 490 |
| 250 × 136 | — | — | — | — |
| 280 × 170 | — | 7.9 | 2410 | 820 |
| 281 × 136 | — | — | — | — |
| 293 × 157 | — | — | — | — |
| 298 × 138 | Wing | — | — | — |
| 320 × 157 | — | — | — | — |
| 330 × 200 | — | 11.0 | 4210 | 1440 |
| 350 × 157 | — | — | — | — |
| 380 × 157 | — | — | — | — |
| 400 × 200 | — | — | — | — |
| 400 × 250 | — | 16.5 | 9560 | 3100 |
| 440 × 180/220 | — | — | — | — |
| 470 × 215 | — | — | — | — |
| 490 × 195 | Wing | — | — | — |
| 500 × 250 | — | — | — | — |
| 625 × 312 | — | — | — | — |
| 740 × 355 | With crossbar | — | — | — |
| 770 × 392 | — | — | — | — |
