The mast is the backbone of any windsurfing rig. Its flexibility, weight and compatibility with the sails largely determine the handling and responsiveness of the rig. RDMs and SDMs, while sharing the same role, differ in diameter, construction and specific advantages. So how do you choose the right one? Let's decipher their characteristics to help you make an informed choice.
Main features of SDM masts
SDM masts are the oldest, and are distinguished by their standard diameter, which is larger than that of RDMs.
- Diameter: 48 to 50 mm approx.
- Weight: generally heavier, although top-of-the-range models are lighter.
- Stiffness: better torsional stability, making them suitable for large sails and strong wind conditions.
- Compatibility: perfect for slalom, freeride and big race sails.
Benefits :
- Ideal for sails with a wide leech and stable profile.
- More economical in basic ranges.
Limits :
- Less maneuverable in transitions.
- More cumbersome, with a diameter requiring suitable extensions and cambers.
Main features of RDM masts
Introduced later, RDM masts are slimmer and often used in technical disciplines.
- Diameter: 32 to 34 mm approx.
- Weight: lighter than SDM, with better carbon distribution for optimized performance.
- Flexibility: a more progressive curvature for improved feel and handling.
- Compatibility: ideal for wave, freestyle and light freeride sails.
Benefits :
- Better grip thanks to their thinness.
- Increased impact resistance, useful in difficult conditions.
- Easy rig furling, even in camberless sails.
Limits :
- Less rigidity for racing sails or large sails.
- Sometimes requires adapters for extension leads.
Differences in real-life conditions
The performance of SDM and RDM masts varies according to the needs of the sailor. SDMs are distinguished by their greater power and stability in larger sails, making them a popular choice for practices requiring greater rigidity, such as slalom. RDMs, on the other hand, are more responsive in transitions, excelling particularly in rough conditions where their maneuverability is a major asset.
In terms of comfort, RDM provides a softer feel, ideal for sailing in waves or chop, as it absorbs shocks better, reducing arm fatigue. In terms of durability, RDM is more resistant to falls and impacts, making it a solid choice for demanding disciplines such as freestyle or wave sailing.
How to choose?
The choice between SDM and RDM depends essentially on the discipline practiced. For freeride and slalom riders, the SDM is the ideal choice, thanks to its performance in large sails and its structural rigidity. On the other hand, for wave or freestyle disciplines, the lighter, easier-to-handle RDM is the natural choice.
Personal preferences also play an important role. Beginners will find in the SDM an accessible and stable ally, favoring a serene learning curve. Regular riders, on the other hand, will appreciate the dynamic sensations and versatility offered by an RDM, perfect for pushing the limits in a variety of conditions.
Before making your choice, always check the sail manufacturer's recommendations to get the most out of your sessions on the water. Some sails are optimized for a specific type of mast, and the wrong choice can adversely affect the curvature and behavior of the rig.
