The Sailboat Rig

The sailboat rig comprises of single handed (one-person) boats usually having a single sail, fitted onto an unstayed mast housed in a large tube or mast support at the front of the boat. Two-person boats, have two or more sails, and a mast which is supported or stayed by three wires.

The mast foot can be either housed on the deck (deck-stepped) or inside the boat (keel-stepped). A fixed mast foot has a tenon which fits tightly into a mortice whereas an adjustable mast foot fits into a track with adjustable pins. A U-shaped adjustable track has holes at regular intervals that accept the two pins that are put in at a chosen position and fix the mast foot to prevent the foot slipping forward or backwards. The inverted T-bar is another type which accepts a grooved mast foot using a single pin to locate the positioned mast.

Unstayed Sailboat Masts

Boats that have the unstayed masts are stored without their mast. This sailboat rig has the mainsail attached to the mast via a sleeve which slides down the mast with the sail being removed or attached only when the mast is unstepped.

Often, unstayed masts are made in two sections that slot together. The sail is then fitted to the mast and lifted vertically and lowered into the mast step. A locking arrangement is fitted in the

step, which secures the mast in place or alternatively a rope downhaul or cunningham line secures the sail and mast to the boat.

Stayed Sailboat Masts

Stayed masts are either stepped on deck or on the keel where a mast step is attached to the boat to accept the mast's heel fitting. Keel-stepped masts sometimes have an adjustable fore-and-aft position of the step with adjustments to allow alterations to the mast position and rake.

With both systems, the mast is braced by wires called standing rigging, being attached to the mast by strip shackles or clevis pins at a fitting called the hounds, being three quarters up the mast. Some wires may be swaged onto T-bar fittings that slot into openings in the mast. Mast supporting wires on catamarans are taken to a single large shackle attached to the front edge of the mast. This allows the mast to rotate so the aerofoil mast is able to align with the wind.

The wires bracing the mast to port and starboard are called shrouds and run through the ends of the spreaders, which are located midway on the mast. Adjusting shroud tension is done with a lanyard, rigging link or bottlescrew which fit between the chainplate and shroud.

The wire running from from the hounds to the bow-fitting is called the forestay and prevents the mast falling backwards and is adjusted with a rigging link. The forestay, keeps the mast in

position when the jib is not rigged. On some boat’s rigging, the jib and forestay are integrated into one and the jib is furled around the forestay.

Sailboat Mast Stepping

For the ease of sailboat rigging and identification, always lash the halyards to the mast before unstepping ensuring they do not foul the operation of unstepping and stepping the mast. Check that the boat is stable when rigging a deck-stepped mast, preferably cradled in its trolley, trailer or stand. The front of the boat should always be pointed into the wind when rigging, as the sail when hoisted, catches the wind and causes the whole structure to fall on its side.

Prior to sailboat mast stepping, check that you are well clear of any overhead power lines and ensure that the boat can be wheeled to the water without the mast coming in contact with power lines or tree branches.

Sailboat mast stepping on small dinghies on can be accomplished by one person, but is easier, and safer, with two people. Most sailing dinghy masts are light in weight but their length and wind resistance makes them unwieldy to lift and therefore hard to step. The sailing dinghy on its trolley in a bow-down position causes the mast to lean forward against the support of the shrouds when placed in its step stabilizing the mast. When lifting the mast, raise it vertically and position the hands quite wide apart giving better leverage.

Mast Rake

Tightening the shrouds beyond their supporting tension causes a bend in the middle of the mast known as 'mast bend', while adjusting the forestay varies the amount of forward or backward slope known as 'mast rake'. Different wind conditions dictate the different settings of the mast.

Once the mast has been stepped, adjust the shrouds and forestay to get the correct rake of the mast. Most boats sail efficiently with masts raked aft slightly with the mast head typically about 6cm/2in aft of the gooseneck with the mast upright in a sideways direction. Mast rake with general-purpose dinghies is not critical, however with racing dinghies it needs to be set precisely to the correct measurement for top performance sailing.

Use the end of the main halyard as a measure at each shroud chain plate to gauge and adjust the shrouds ensuring that the mast isn’t leaning to one side. Apply tension to the shrouds to produce an equal ‘twang’ when plucked.

Keel Stepping

Keel-stepped masts are easy to step, where the mast heel is positioned into its step prior to it being pulled into the upright position with the mast being held securely in the mast gate.

• Lay the mast and rigging on the boat with the masthead to the stern of the boat.
• Rest the mast heel on the mast step with the front side of the mast uppermost.
• Attach the two shrouds to the chainplates on the sidedecks.
• One person lifts the mast and positions the heel into the mast step.
• The other person pulls on the forestay.
• The person supporting the mast guides it into the mast gate.
• The other person attaches the forestay to the bow fitting
• Close the deck level mast gate.
• Tension the shrouds.
• Adjust the shrouds and forestay to get the desired rake and mast bend
• Make sure that the halyards are not twisted around the rigging

Deck Stepping

Deck-stepped masts are not supported by a mast gate and therefore must be lifted vertically, before being located into the mast step therefore less stable until the rigging is secured.

• Lay the mast on the ground next to the boat with the aft side uppermost and the mast head towards the bow.
• Attach the shrouds to the chainplates.
• Stand the mast vertically alongside the boat.
• Lift the mast in the vertical position until it can be stepped.
• Slot the mast into the recessed fitting in the foredeck.
• Held by the shrouds, allow the mast to lean forwards.
• Attach the forestay to the bow-fitting.
• Tension the shrouds.
• Adjust the shrouds and forestay to get the desired rake and mast bend.
• Ensure the halyards are not twisted around the rigging.

Sail Boom

The foot of the mainsail may fit into a groove along the top of the main boom or be only attached by the outhaul device at the end of the boom . The boom is a horizontal spar, comprising of aluminium or wood, attached by a gooseneck fitting to the aft side of the mast. On some rigs this may be fixed in a position, or or have a sliding fitting which allows the boom to be adjusted up or down.

The tack of the mainsail is held in position close to the mast by a fitting on the gooseneck and the clew is secured to the clew outhaul device by either rope or shackle. The clew outhaul enables the foot of the sail to be tensioned and is used to alter the shape of the sail.

The sail foot is tensioned overall with a kicking strap, kicker or boom vang fitting, which attaches to the underside of the boom, a quarter distance from the mast, and to the base of the mast. It comprises of a block and tackle which tensions the sail and cleated at the right tension.

Halyards

In addition, the mast is fitted with wire or rope halyards that are used to raise and lower the sails. Designed to run inside the mast, they run through pulley block sheaves at the top of the mast and exit in a sheave box, being an alloy casting, that is incorporated the mast foot.

The jib halyard sheave is positioned at the front of the mast below the forestay fitting, with the spinnaker halyard sheave above the forestay. The halyards are led down to small small swivel blocks or fixed rings. The mainsail halyard sheave is often incorporated into the mast head fitting at the back of the mast inside the sail track. Older rigs have external halyards that run through pulley blocks at the appropriate position for main, jib and spinnaker.