A spreader is a spar on a sailing boat used to deflect the shrouds to allow them to better support the mast. The spreader or spreaders serve much the same purpose as the crosstrees and tops in a traditional sailing vessel. Spreader design and tuning can be quite complex.
What is the purpose of spreaders on a mast?
Spreaders are used on most Rigs to improve Mast support by increasing Upper (and Intermediate) Shroud angles. Spreaders are specific to particular Spreader Bases (or Spreader Bars), which, in turn are specific to individual Mast Sections.
How does mast rake affect performance?
When you add rake to the mast, you tilt the whole sail plan aft. This, in turn, shifts the power aft, pushing more load on the stern and forcing the bow up into the wind, creating weather helm.
How are spreaders attached to the mast?
They hold up the shrouds that hold up the mast
Spreaders are struts attached to the sides of a mast to hold the shrouds away from the mast and increase the angle at which they meet the mast.
What is a port spreader?
Port Spreader
This side is considered the personal flag side of the boat. It is recommended that you only fly one burgee on the halyard as opposed to flying every burgee you have on board.
What is a double spreader mast?
The usage of a double spreader rig allows the mast to be “less weight” or “less weigh aloft” a definite advantage over the usually heavier single spreader rig.
What are diamond stays?
The Diamond Stays:
The Diamond stays are the stainless steel rods, which attach just below the hounds and just above the gooseneck. The diamond stays play a critical role in the tuning of the Lido and unfortunately it is a role far too often neglected.
How tight should mast stays be?
The mast stays in aligment as the tension is increased. The forestay and backstay should be tightened to about the same tension as the upper shrouds, allowing for approximately 1° to 1.5° of aft rake. This rake will improve upwind performance and allow the rig to set in the correct position when the sails are set.
What is a mast jack?
The mast jack system consists of a hydraulic cylinder located inside the mast. The cylinder piston moves down vertically through the heel of the mast to a steel plate in the boat’s T-base, thereby lifting the mast and increasing the tension.
Why are masts raked?
Specifically, a raked mast lifts the end of the boom as it is eased out. This is good for offshore work, as it keeps the boom from dipping in the water and possibly breaking when the boat rolls deeply.
What is helm sailing?
Helm – A tiller or wheel and any associated equipment for steering a ship or boat. Ours is a wheel and we let our passengers take the helm at times during the cruise.
What is a starboard spreader?
The starboard spreaders are used for signalling. This is where both a courtesy flag and the Q flag, as signals, should be flown. These days it is becoming increasingly common for yachts to fly a burgee from the starboard spreaders because of instrumentation sited at the main masthead.
What is a crane spreader?
A spreader bar is a type of below-the-hook lifting device used to aid crane operators in picking up large and sometimes heavy loads. The idea behind a spreader bar is to simply distribute the load of a lift across more than one point, increasing stability and decreasing the loads applied during hoisting.
What is a glass spreader?
Glass spreaders are shaped glass rods used for spreading bacteria onto worm plates during the chunking worms protocol.
What does a boom vang do?
A boom vang (US) or kicking strap (UK) (often shortened to “vang” or “kicker”) is a line or piston system on a sailboat used to exert downward force on the boom and thus control the shape of the sail.
What is a jumper on a sailboat?
The jumper strut is located on the forward side of the mast jutting out horizontally forward, and combats the strain of the mainsail pulling aft on the mast.Diamond stays and jumper stays are not required on all boats; just on those masts which require additional support.
What is standing rigging on a sailboat?
Standing rigging comprises the fixed lines, wires, or rods, which support each mast or bowsprit on a sailing vessel and reinforce those spars against wind loads transferred from the sails.
How tight should shrouds be on sailboat?
They should be tight enough that when you push or pull on them, they don’t want to jiggle around too much. If they feel loose or floppy, you need to tighten them further. Once the cap shrouds are set, the rest of the shrouds simply follow in sequential order with none of them being tighter than the cap shrouds.
How much tension should a sailboat rig have?
The caps should be tighter than with a masthead rig, with no significant slack on the leeward side when the boat’s hard on the wind and heeling 15-20°. If the static tension is up to 25% but the leeward cap is always slack, the boat might be bending.
How do you stop weather helm?
Five Steps You Can Take to Reduce Weather Helm
- Increase weight to windward. Move your crew to windward to reduce heeling and flatten the boat.
- Ease the mainsheet and Genoa sheets.
- Slide the mainsheet car to leeward.
- Move Genoa sheet blocks aft.
- Reduce sail area (reefing; smaller headsail).
How much can a boat heel?
Let me offer a few simple suggestions to control helm and heel, but first, let’s look at the question of how much heel is appropriate. In quantitative terms, the answer is probably somewhere between 20 and 25 degrees maximum for a displacement monohull, depending on boat specific characteristics.
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