By Jon Paige, Rigging Manager, Crowley's Yacht Yard
Email: jon@crowleys.com
As a Yacht Rigger, one of the most common questions I get asked is “When should I replace my standing rigging?”. There is actually a simple answer which is: “It depends”. Navtec, makers of rigging and hydraulics recommend that 316-grade stainless steel wire standing rigging has a lifespan of between 15 and 20 years in freshwater sailing environments, less in saltwater, and even less in warm saltwater, year around locations such as the Caribbean. But that doesn’t mean your standing rigging is going to explode in a fireball exactly 20 years to the day after it was made. Indeed, here at Crowley’s and in many other boatyards in the Great Lakes region, you will find sailboats with standing rigging that is approaching 30, and even 40 years of age, with no visible signs of imminent failure. Why is this? Because it turns out that the life of the rigging has a lot to do with the safety factor with which it was originally designed.
But that still doesn’t answer the question about your rigging. What type of sailing do you do? Racing, cruising, or a mixture of both? How often do you sail? In what wind strengths? How do you store your rig over the winter? Was your boat built for performance or comfort and safety? Was your boat designed and built for offshore waters? Coastal waters? Inland waters?
All of the these factors will affect the lifespan of your rigging. Boats that are raced will experience more loading on the standing rigging, due to the fact that the boat will probably be used more often and in conditions where the cruising sailor may decide not to venture out of their slip. Winter storage is also a determining factor; if the mast is unstepped and tucked away for five months of the year, the rigging is effectively unloaded. If the mast is stepped over the winter the rigging is tensioned and being loaded and unloaded (known as cycling) continuously as the wind causes the mast to oscillate while the boat sits in the cradle. This continues to fatigue the rigging even in the off season.
The type of boat you are sailing is also an important consideration. A custom designed and built, carbon fiber, Grand Prix racing yacht is going to have rigging with a lower factor of safety built into the rigging specifications. It was probably also expected that the rigging would be replaced more often due to the higher loads (and therefore higher percentage of the breaking load) that would be placed on the rig. In contrast, a blue-water cruising yacht will have a much higher safety factor so the rigging tension will be at a smaller percentage of the breaking load. Due to this, it will last longer.
A thorough mast and rigging inspection is a good idea and should be performed once a year by a professional rigger after the rigging reaches the 15 to 20 year mark. The obvious things to look for are broken wire strands, cracked swages and anywhere there is a lot of rust staining.
Broken strands (pic 1) are normally found where the wire enters the swaged terminal. The strand may be obvious and pop out of the terminal or you may have check each strand with a small flat-blade screwdriver (be careful not to damage the strands!).
Clean and polish the swaged part of the terminal to make it easier to spot any cracks (picture 2). Terminals which have a lot of rust staining pouring out should be checked very closely. If the rigging is over 15 years old, this can indicate problems occurring inside the swaged part and replacement should be considered.
As always, give us a call if you have any questions or send an email to lakesidestory@crowleys.com
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