Sailboat boom

epoxy resincarbon fiber

Overview
Just like the carbon masts, the carbon booms are also created in our production facility in southern Germany - design and production from a single source. The main features are: Low weight, fittings with attention to detail and exclusive design.

Laminate structure and reinforcements
Our manufacturing technology enables a special structure of the laminate. The fiber course can be implemented exactly according to the calculations. The material used - high-quality fibers from renowned manufacturers - guarantees the qualitatively convincing result. CUL-Masten attaches particular importance to high tensile strength and elongation at break. The combination of different fibers is possible and can even further improve the result. CUL-Masten uses a high quality epoxy resin, which is also used in aviation, with GL certified hardener, which has a temperature resistance of well over 100° C. The carbon fiber main boom is reinforced in the area of the downhaul and the mainsheet, as well as at the reefing points, in order to absorb the corresponding forces.

Luff flying or guided in the groove
A particular advantage of the CUL Carbon large beams is the possibility of supplying them with an integrated lower luff groove. This is incorporated directly into the laminate, saves weight and increases the strength in the bending axis. Alternatively, the booms can also be supplied without or with a closed luff groove in order to use a flying luff.

Details from the Lümmel fitting to the roller box
Boom neck fitting

• with up to 4 halyards for foot luff and reefs
• easy running and resilient drop discs
• easy to dismantle and therefore easy maintenance of the lines
• stable and maximum load bearing
• stainless steel
• different variations possible depending on customer requirements

Kicker / Downhaul fitting

• stainless steel or carbon
• suitable for CUL-Power-Kicker or other pusher systems
• different variations possible depending on customer requirements

Strap for mainsheet

• simply
• light
• durable
• different variations possible depending on customer requirements

Velcro strap for clew

• simply
• light

Roller box with up to 3 halyards

• completely made of carbon fiber therefore very light
• with 3 halyards for foot and 2 reefs
• easy running and resilient drop discs
• easy to dismantle and therefore easy maintenance of the lines
• eye for dirkleine
• perfect load distribution
• pulleys can be integrated in the boom

Gallery / Applications (selected)
CUL Carbon Boom variants and applications shown for: Nissen 42 (silver matt lacquered, with lazy jacks, single line reef systems), dinghy Korsar, Streamline 2021, international 5.5 (with spinnaker pole holder and stainless steel fitting), dinghies and small keelboats (e.g. Korsar, 505er, FD, Contender).

Profile sizes
Profile size | Dimensions | Groove | Weight | Ixx | Iyy
44er Profil | Ø44 mm | without groove | 0,4 kg/m | 5,8 cm⁴ | 5,8 cm⁴
46er Profil | Ø46 mm | without groove | 0,6 kg/m | 9,4 cm⁴ | 9,4 cm⁴
65er Profil | Ø65 mm | without groove | 0,7 kg/m | 24 cm⁴ | 24 cm⁴
99er Profil | 99 x 67 mm | without groove | 0,9 kg/m | 39 cm⁴ | 73 cm⁴
101er Profil | 101 x 67 mm | without groove | 1,1 kg/m | 40 cm⁴ | 86 cm⁴
104er Profil | 104 x 67 mm | with groove | 1,1 kg/m | 39 cm⁴ | 85 cm⁴
106er Profil | 106 x 67 mm | with groove | 1,2 kg/m | 40 cm⁴ | 100 cm⁴
117er Profil | 117 x 78 mm | without groove | 1,0 kg/m | 61 cm⁴ | 113 cm⁴
117er Profil | 117 x 78 mm | with groove | 1,2 kg/m | 62 cm⁴ | 132 cm⁴
118er Profil | 118 x 79 mm | without groove | 1,3 kg/m | 74 cm⁴ | 138 cm⁴
118er Profil | 118 x 79 mm | with groove | 1,5 kg/m | 76 cm⁴ | 157 cm⁴
139er Profil | 139 x 88 mm | without groove | 1,6 kg/m | 127 cm⁴ | 262 cm⁴
140er Profil | 140 x 88 mm | with groove | 1,7 kg/m | 130 cm⁴ | 312 cm⁴
141er Profil | 141 x 88 mm | without groove | 1,9 kg/m | 129 cm⁴ | 316 cm⁴
142er Profil | 142 x 88 mm | with groove | 2,0 kg/m | 132 cm⁴ | 366 cm⁴
163er Profil | 163 x 108 mm | without groove | 1,8 kg/m | 216 cm⁴ | 406 cm⁴
167er Profil | 167 x 108 mm | without groove | 1,9 kg/m | 219 cm⁴ | 490 cm⁴
168er Profil | 168 x 108 mm | with groove | 2,1 kg/m | 226 cm⁴ | 603 cm⁴
170er Profil | 170 x 108 mm | with groove | 2,5 kg/m | 266 cm⁴ | 738 cm⁴
195er Profil | 195 x 110 mm | without groove | 2,7 kg/m | 362 cm⁴ | 886 cm⁴
197er Profil | 197 x 110 mm | without groove | 2,9 kg/m | 367 cm⁴ | 1007 cm⁴
197er Profil | 197 x 110 mm | with groove | 3,0 kg/m | 370 cm⁴ | 1069 cm⁴
199er Profil | 199 x 110 mm | with groove | 3,2 kg/m | 375 cm⁴ | 1220 cm⁴
217er Profil | 217 x 113 mm | without groove | 3,0 kg/m | 414 cm⁴ | 1045 cm⁴
218er Profil | 218 x 113 mm | with groove | 3,3 kg/m | 421 cm⁴ | 1354 cm⁴
219er Profil | 219 x 115 mm | without groove | 3,8 kg/m | 528 cm⁴ | 1400 cm⁴
220er Profil | 220 x 115 mm | with groove | 4,1 kg/m | 536 cm⁴ | 1684 cm⁴

Characteristics / technical specifications

• Manufacturer: CUL-Masten (Carbon Ultra Light)
• Material: carbon fiber laminates with combinations of high-quality fibers possible
• Resin system: high-quality epoxy resin (aviation grade) with GL certified hardener; temperature resistance well over 100° C
• Reinforcements: reinforced at downhaul area, mainsheet area and reefing points
• Luff options: integrated lower luff groove incorporated into laminate (weight saving, increased bending strength) or supplied without/closed groove for flying luff
• Boom neck fitting: up to 4 halyards, drop discs, service-friendly, stainless steel options
• Kicker/downhaul fitting: stainless steel or carbon, compatible with power kicker systems
• Mainsheet attachments: lightweight, durable strap solutions; variations per customer request
• Clew fastening: Velcro strap options (simple, light)
• Roller box: fully carbon, very light, up to 3 halyards, pulleys can be integrated, designed for perfect load distribution
• Available lengths/profiles: carbon booms up to 8 m in length; wide range of profile sizes (44er–220er) with detailed dimensions, weights and section properties listed above
• Typical applications: sport boats, dinghies, dinghy cruisers and yachts up to ~50 ft depending on profile