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Windsurf Sail Masts Buying Guide

A windsurf mast is an essential accessory that brings the difference between a typical paddle surfer and a serious windsurfer. Although early sailors and surfers gave little attention to sail masts, these accessories play a key role in completing your windsurfing gear. The sail mast you pick should match the sail you’re going to use. Using a wrong mast will not only deform your sail but also messes up with your windsurfing performance. When selecting the right sail mast, consider factors such as:

Mast length

Sail masts come in different lengths and sizes just like sails. As a rule of thumb, it is recommended that you choose a mast length that is slightly shorter than the sleeve of the mast. Manufacturers often produce masts in standard lengths such as 370 cm, 400 cm, 430 cm, and 460 cm just like sails. Selecting a long mast may not be ideal as it can affect your sailing performance. Find a mast length that is closer to the luff length of your sail.


Masts are made by combining carbon and glass fiber. The importance of carbon is that it is lightweight and retains the original form fast. High carbon content implies a high-quality mast although the higher the carbon content, the pricier the sail mast. Carbon composition varies ranging from 30-100%. A composition of 60-80% is ideal for most average surfers, but a 100% carbon is good in case of performance-oriented windsurfing. Glass fiber was used in old masts and can be dangerous in case it breaks.

Bend quality 

Masts may have uniform lengths but bending quality differ. Bending is classified into three categories i.e. hard top, flex top, and constant curve. Flex top masts have soft tops while hard tops have soft lower ends. Masts with constant curve often bend uniformly at both ends. Bending quality affects both your sailing power and stability in case of strong winds. Determining the right bend quality for your sail can prove to be a challenge especially for first-timers. To avoid this, pick a mast that is recommended by your sailmaker. 

Stiffness level

The extent by which the mast deflects from the center is called stiffness. The level of deflection can determine whether your sail will be enjoyable or not. Stiffness should match the one specified on your sail. Choosing a higher stiffness than recommended can imply limited deflection. Other effects of using stiffer masts include more power, fuller profile and tighter leech. Masts with high stiffness are good for heavier riders as it provides too much deflection. On the other hand, low stiffness implies less stable sails and more deflection. A low level of stiffness produces a flat profile and a soft feel. Masts with low stiffness are best-suited for lightweight riders.

Mast stiffness is often determined by supporting the mast at each end then applying a weight of about 30kg at the center. Taking into account the mast length, an IMCS number is obtained. A mast with a big IMCS number is considered stiff. The numbers can vary from 11 to 36.  


There are standard diameter mast and reduced diameter mast. SDMs come with tubes with a larger diameter in the lower parts and thinner walls. SDMs are low weight and deliver higher dynamic performance. If you’re planning to engage in racing sails, then SDMs would be appropriate. RDMs are flexible and guarantee soft and easy-to-control sails. They are great when sailing in strong winds. Reduced diameter masts are slightly heavier than standard diameter masts. They provide good grips and are easy to maneuver around. RDMs are mostly used in freestyle sailing, waves, and competitive rides.

Summary of key factors to consider when buying sail masts

• Your weight matters a lot. If you are heavyweight, then you might need a stiffer mast but lightweight individuals are advised to select soft ones. Always go with what your sail manufacturer recommends. 

• Winds speed is also critical. Flex top masts are good for use in gusty and strong winds while stiff tops are best-suited for light winds. Constant curves are standard masts that are suitable for use anywhere. In fact, they are the most recommended masts. 

• Regarding carbon composition, go for a high carbon percentage depending on your budget. Higher carbon content means more pleasure.

• Finally, thickness determines the maneuverability of your sail mast. SDMs are good for racing while RDMs are better when it comes to free rides.