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The question of maintaining electrical sheathing in masts concerns many sailboat owners, whether they're sailing offshore or afloat in a marina. Bells ringing at anchor, sheaths flapping in the mast, inaccessible or damaged cables: the constraints are numerous. Today's yachtsmen use a number of methods to effectively stabilize internal circuits in the mast.
One duct per function for easy maintenance
Separating electrical functions makes maintenance easier. Some sailors recommend using one tube for each type of cable: VHF, windvane, navigation lights or deck lighting. This distribution provides better access to circuits when servicing. IRO tubes (rigid PVC tubes used by electricians in the building trade) are often used for their lightness and low cost. Glued together to prevent vibration-induced slippage, they offer a robust, modular structure.
The use of plastic collars to center sheaths
Plastic collars acting like shock-absorbing springs A technique often recommended is to connect the IRO tubes together with plastic collars (Rilsans or Colson) at 75 to 80 centimetre intervals, staggering them by 120 degrees to ensure symmetry. By not cutting the excess collars, the remaining tabs act like springs, keeping the whole assembly centered in the mast. This solution absorbs movement and limits noise, without completely immobilizing the structure so as not to impede the movement of the halyards. We recommend securing the clamps to the IRO tube with Scotch tape to prevent them from slipping over time.
Rivet at top and bottom to secure sections
Depending on the configuration, the sheaths can simply be riveted at the top and bottom of the mast, leaving the intermediate segments free but stabilized by the clamps. Some recommend that collars should not be positioned closer than 1.50 m from the riveting points, to avoid tension.
An alternative solution: insulating foam
Less technical, but effective, is the use of foam insulation for air-conditioning pipes in which the cables run, to reduce noise at lower cost. Some yachtsmen achieve sufficient damping by slipping sheaths over the cables and taping the sections together.
A project requiring the dismantling of the yacht
Dismasting, an essential operation for accessing the interior of the profile. In all cases, centering and sheathing operations require complete dismasting of the yacht. This is the ideal opportunity to check the entire rig, inspecting sheaves, fittings and hardware. It's a time-consuming operation, but one that will provide sound comfort on board, especially at anchor.
