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A stubborn and resistant headsail furler that jams, or releases and jams alternatively when furling




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What is the issue?
The headsail furler jams or is highly resistant to furling. Or, the furling system will partially furl then stops, and then furl again, and then stops etc. A complete furl may be achieved but it is a battle and the furler rotation is far from smooth or consistent.

These are the symptoms of 'halyard wrap', the number one issue that causes furling systems to jam or be rotation resistant. What is happening is that the halyard is starting to wrap at the top, locking up the furling system, and then unwrapping when you ease the pressure on the furling line.

Why address this?
The last thing you want from your furling gear is for it to jam up, and certainly not in a rising breeze. Worse, even slight damage from minor episodes of halyard wrap can ruin the halyard, the foil and the headstay connection into the terminal fitting. As the headstay supports the mast you cannot risk any damage to it. Even minor damage will necessitate a replacement and this is a seriously expensive proposition.

How to address this?
If you ever experience resistance when furling the headsail it is most likely to be halyard wrap. A glance aloft and you can expect to see the halyard is bound around the headstay and foil.

Sheave to prevent halyard wrap
Photo: Tony Gibson
Halyard wrap occurs around the forestay and foil in the gap between the sheave exit and upper halyard swivel. It occurs when the angle between the genoa halyard and the headstay is too shallow or as a rule of thumb... the bigger the gap, or the shorter the sail, the more likely it is to occur. As the halyard is running parallel to the forestay and foil the upper half of the swivel tends to rotate with the rest of the sail causing the halyard to wrap around it - hence the term 'halyard wrap'. This can also happen if the halyard is slack and the lead is too close to the foil. It can get caught up on the rotating foil during sail furling. Either way, as it wraps around it slowly binds uptight loading up the furling system and grinding it to a halt so that it is prevented from rotating.

The immediate remedy is to release it by alternately pulling on the sheets and furling line. If it is badly bound up someone may have to go aloft to unwrap the halyard. Although you may be frustrated enough to resort to force, and believe me I know that feeling, don't use a winch to operate the furling system. The force of the winch could break the furling system and worse, cause the headstay itself to fail.

The solution to halyard wrap is to rearrange the upper halyard swivel position. Adjust the height and angle by adding a pennant to the head of the sail which allows the upper halyard swivel to get closer to the sheave box. The closer the swivel goes to the sheave box, the less parallel the halyard is to the foil and headstay, the less likely it is to wrap. This is the basic formula to be observed for halyard wrap solutions, the more this angle is opened up the less likely the halyard is to wrap. Be certain to add the pennant to of the head of sail as opposed to the foot where it may blow out the luff. If you cannot make this work a halyard restrainer or diverter can be mounted on the mast to increase the angle of the halyard.

Another entirely different approach is to bulk out the headstay or furler with a "Wrapstop" attachment to make the area too big for the halyard to get around it. Profurl has a bolt on Darth-Vader-Helmet like device and there are many others. I discovered my halyard wrap in the deepest Pacific with little equipment to resolve the issue. By chance, I addressed it by simply attaching a second and spare halyard from the back of the mast that pulled a 45° angle upon the top swivel, which prevented it from rotating.

Most modern mast manufactures are positioning jib halyard sheaves to provide an optimal furler lead so this problem will go away. If you are still having furling problems and you have eliminated halyard wrap you may have too much halyard tension or a loose forestay.

The former is caused by a tendency to grind in the halyard and place too much tension on the swivels so they slightly twist and bind up. This is a common mistake and there should be just enough tension applied on the halyard to get the wrinkles out of the luff. A loose forestay will allow the furler to work, but the sail will be lumpy and bumpy as it has not got a straight axle to rotate around. If you see this happening you need to immediately address the vessels rig tension.

With thanks to:
Michael Harpur, Yacht Obsession.

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