What is the difference between reefing furlers and non-reefing furlers?

Are you on the market for a furler and not sure what to look for or which way to go?

The very first question you will have to answer is whether you want to be able to reef your sails (in other words reduced the sail that will be used with your furler) or not. This will help you identify what type of furlers to look for:

  • If you want to reef your sail, you will be looking at a furling unit that will be permanently rigged around a fixed stay
  • If do not want to reef your sail, you will be looking at a furling unit that could be removable or integrating the forestay itself

Reefing furlers

Reefing furlers were designed to facilitate reducing the surface area of a foresail and are now commonly installed on production boats. They are typical equipment for the genoa or the staysail on cruising boats.

Reefing-furlers are permanently rigged and fit on or around a stay (forestay or babystay), being connected to a chainplate on the deck and a tang on the mast. It is composed of a drum, which integrates extrusions (also known as foils) and a top swivel. The extrusions are designed with a groove (single or double), where the luff tape of the sail will slide into to be hoisted. The top swivel is designed to enable the halyard to stay in line with the exit point on the mast when the sail is being furled.

When pulling on the furling line, the torque would be transferred through the extrusion from the drum along the luff, enabling the sail to be furled. When the sail is not used, it will be furled around the stay (rather than being lowered, removed and stowed away).

Extrusions can be of different shapes (rounded or oval) and manufactured in different material (aluminum or carbon), depending if you are cruising or racing.

The choice of a reefing furler will often depend on the length of the yacht and the forestay diameter. Often, the manufacturers offer different sizes of clevis pin for one model to fit the attachment point on deck.

Reefing furler - Profurl coastal range

Possible to reduce sailsShape of the sails when reduced
Easy to reduce the sailWeight of the system overall
Jib permanently riggedLongevity of the sail
Free-up storage spaceShortened luff sail due to the height of the drum
Increased safety on the foredeck
Easy maintenance
Easy to dry the sails

Non-reefing furlers

Non-reefing furlers were originally designed to facilitate handling of what is known as “free flying sails”. Free flying sails are all the sails that are not permanently rigged unlike a genoa (staysail, code 0, reaching sails, asymmetric spinnaker …) and which can be stowed in their bags when not used while furled on themselves.

These units are often referred to as “continuous line furlers”, but that would be quite restrictive as many manufacturers have also developed single line furlers within their range. The common factor is that they are composed of two parts (drum and top-swivel) connected together by a stay (usually in composite) that transfers the torque from the drum to the top swivel, making it possible to furl the sail. This stay is commonly known as the anti-torsion cable. This cable features lashing thimbles on each end that will connect into the fork of the drum and top swivel. The sail will be attached to these thimbles with a lashing.

When one wants to furl the sail, it will pull on the furling line, the drum will start to rotate, generating the stay to transfer the torque to the top swivel, making possible to furl the sail. There are two different ways to furl the sail: bottom-up or top-down. We will cover the different methods of furling a sail in a future blog post.

The choice of a continuous line furler will often depend on the length of the yacht, the type of sail and the surface area. Other factors like the program (racing/cruising, offshore/inshore), the crew (solo/shorthanded or full crew) should also be considered to select th right unit.

Non reefing furler - Ubi Maior FR125

KZ Racefurlers furling gear at the factory

Non-reefingfurler - KZ Racefurlers

Lightweight of the system overallSail either completely-in or completely-out
Easy to handle free-flying sailsRequires having space for storage
Longevity of sails
Sail area optimized due to compact drum and swivel
Increased safety on the foredeck
Easy maintenance
Facnor Flatdeck jib furler with Profurl Spinex Top down furler

Facnor Flatdeck jib furler (reefing furler) with a Profurl Spinex top down furler (non-reefing furler) onboard Dufour Yachts