How to Identify Sailboat Stays
Sailboat stays connected to the top of the mast to the deck of the sailboat. Stays stabilize the mast in the forward and aft directions. Stays are typically mounted to the very front of the bow and the rearmost part of the stern.
Sailboat Forestay
The forestay connects the top of the mast to the bow of the boat. The forestay also serves an additional purpose—the jib sail luff mounts to the forestay. In fact, the jib is hoisted up and down the forestay as if it were a mast.
Boats equipped with roller furlings utilize spindles at the top and base of the forestay. The spindles rotate to furl and unfurl the jib. Roller furlings maintain the structural integrity of a standard forestay.
Sailboat Backstay
Backstays aren't as multifunctional as forestays. The backstay runs from the top of the mast (opposite the forestay) to the stern of the sailing vessel, and it balances the force exerted by the forestay. Together, the forestay and the backstay keep the mast upright under load.
Sailboat Stay vs. Shroud
Stays and shrouds are often confused, as they essentially do the same thing (just in different places). Stays are only located on the bow and stern of the vessel—that's fore and aft. Shrouds run from the port and starboard side of the hull or deck to the top of the mast.
Best Sailboat Stay Materials
Traditional sailboat stays were made of rope and organic line. These materials worked fine for thousands of years, and they still do today. However, rope has limitations that modern sailboat stays don't.
For one, traditional rope is organic and prone to decay. It also stretches, which can throw off the balance of the mast and cause serious problems. Other materials, such as stainless steel, are more ideal for the modern world.
Most modern fiberglass sailboats use stainless steel stays. Stainless stays are made of strong woven stainless steel cable, which resists corrosion and stress. Stainless cables are also easy to adjust.
Why are Stays Important?
Stays keep the mast from collapsing. Typical sailboats have lightweight hollow aluminum masts. Alone, these thin towering poles could never hope to withstand the stress of a fully-deployed sail plan. More often than not, unstayed masts of any material fail rapidly under sail.
When properly adjusted, stays transfer the force of the wind from the thin and fragile mast to the deck or the hull. They distribute the power of the wind over a wider area and onto materials that can handle it. The mast alone simply provides a tall place to attach the head of the sail, along with a bit of structural support.
Sailboat Chain Plates
Sailboat stays need a strong mounting point to handle the immense forces they endure. Stays mount to the deck on chainplates, which further distribute force to support the load.
Chainplates are heavy steel mounting brackets that typically come with two pieces. One plate mounts on top of the deck and connects to the stay. The other plate mounts on the underside of the deck directly beneath the top plate, and the two-bolt together.
Mast Stay Mounting
Stays mount to the mast in several ways depending on the vessel and the mast material. On aluminum masts, stays often mount to a type of chain plate called a "tang." A tang consists of a bracket and a hole for a connecting link. Aluminum masts also use simple U-bolts for mounting stays.
Wooden masts don't hold up to traditional brackets as well as aluminum. A simple u-bolt or flat bolt-on bracket might tear right out. As a result, wooden masts often use special collars with mounting rings on each side. These collars are typically made of brass or stainless steel.
Sailboat Stays on Common Rigs
Stays on a Bermuda-rigged sailboat are critical. Bermuda rigs use a triangular mainsail. Triangular sails spread their sail area vertically, which necessitates a tall mast.
Bermuda rig masts are often thin, hollow, and made of lightweight material like aluminum to avoid making the boat top-heavy. As a result, stays, and shrouds are of critical importance on a Bermuda rig.
Traditional gaff-rigged sail plans don't suffer as much from this issue. Gaff rigs use a four-pointed mainsail. This sail has a peak that's taller than the head and sometimes taller than the mast.
Gaff-rigged cutters, sloops, schooners, and other vessels use comparatively shorter and heavier masts, which are less likely to collapse under stress. These vessels still need stays and shrouds, but their stronger masts tend to be more forgiving in unlucky situations.
How to Adjust Sailboat Stays
Sailboat stays and shrouds must be checked and adjusted from time to time, as even the strongest stainless steel cable stretches out of spec. Sailboats must be in the water when adjusting stays. Here's the best way to keep the proper tension on your stays.
Loosen the Stays
Start by loosening the forestay and backstay. Try to do this evenly, as it'll reduce the stress on the mast. Locate the turnbuckles and loosen them carefully.
Match the Turnbuckle Threads
Before tightening the turnbuckle again, make sure the top and bottom threads protrude the same amount. This reduces the chance of failure and allows you to equally adjust the stay in both directions.
Center the Mast
Make sure the mast is centered on its own. If it's not, carefully take up the slack in the direction you want it to go. Once the mast is lined up properly, it's time to tighten both turnbuckles again.
Tighten the Turnbuckles
Tighten the turnbuckles as evenly as possible. Periodically monitor the direction of the mast and make sure you aren't pulling it too far in a single direction.
Determine the Proper Stay Pressure
This step is particularly important, as stays must be tightened within a specific pressure range to work properly. The tension on a sailboat stay ranges from a few hundred pounds to several tons, so it's essential to determine the correct number ahead of time. Use an adjuster to monitor the tension.
What to Do if you Lose a Stay
Thankfully, catastrophic stay and shroud failures are relatively rare at sea. Losing a mast stay is among the worst things that can happen on a sailboat, especially when far from shore.
The stay itself can snap with tremendous force and cause injury or damage. If it doesn't hurt anyone, it'll certainly put the mast at risk of collapsing. In fact, if you lose a stay, your mast will probably collapse if stressed.
However, many sailors who lost a forestay or backstay managed to keep their mast in one piece using a halyard. In the absence of a replacement stay, any strong rope can offer some level of protection against dismasting.
How to Prevent a Stay Failure
Maintenance and prevention is the best way to avoid a catastrophic stay failure. Generally speaking, the complete failure of a stay usually happens in hazardous weather conditions or when there's something seriously wrong with the boat.
Stays sometimes fail because of manufacturing defects, but it's often due to improper tension, stripped threads, or aging cable that hasn't been replaced. Regular maintenance can prevent most of these issues.
Check the chainplates regularly, as they can corrode quietly with little warning. The deck below the chainplates should also be inspected for signs of rot or water leakage.
When to Replace Standing Rigging
Replace your stays and shrouds at least once every ten years, and don't hesitate to do it sooner if you see any signs of corrosion or fraying. Having reliable standing rigging is always worth the added expense.
Choosing a high-quality stay cable is essential, as installing substandard stays is akin to playing with fire. Your boat will thank you for it, and it'll be easier to tune your stays for maximum performance.
