Please select your home edition
Edition
upffront 2018 Generic 728x90

What Information Do I Need to Provide for a Complete Genoa Reefing System Specification?

by Kerri Robson 8 Jul 01:00 PDT
Facnor FlatDeck Furling System © Facnor

So, you're in the market for a new genoa reefing system... either your existing furling unit is extremely old - and spare parts aren't available any more - or you're choosing to switch from a forestay with hanks for more comfortable cruising.

If you belong to the latter, you might be a bit confused about what information you need to relay to the supplier (upffront.com!) in order to be matched with your perfect furling system.

Although some manufacturers can provide a ball park furler suggestion based on boat size, the following pieces of information are the primary requirements to find your ideal furling solution.

Forestay Wire Diameter

  • The most important of them all! To choose the correct furler, your supplier needs to know the diameter of your forestay and the material it is made from - for example, wire, rod or Dyform.
  • This is important as a rod (commonly used for racing) or Dyform forestay (high-performance wire!) may have a smaller diameter, but greater strength than a wire forestay.
  • You also need to decide whether you want to keep the old forestay or not. In a lot of cases it can be possible to have your existing forestay modified or shortened to fit the new system - although some (for example, Seldén's Furlex) include a new wire as standard.
  • Before you decided to re-use, you should have a professional rigger perform a safety check on the existing forestay, as fatigue can be hard to spot.

Forestay Length

  • The length of your forestay will impact the number of foil sections required in your furling system.
  • Make sure to double check the length included in the price of your furler - most manufacturers provide a standard number, but additional foil sections may need to be bought to achieve your desired length.

Drum Height

  • When choosing your new furling system, it is important to consider the position of the drum - high, or low?
  • The performance option, a lower drum will allow the sail to have a longer luff length = more sail area.
  • In comparison, a higher drum will raise the foot of the sail and provide better visibility under the genoa. This option is often chosen by cruising sailors due to safety considerations.
  • Drum heights can be varied by choosing either short or long link plates which connect the drum to the deck chainplate.

Turnbuckle Width

  • Not normally an issue, but it is important to check the width of your turnbuckle, to ensure it will fit inside the furling drum.
  • If your turnbuckle is too wide, changing the turnbuckle for one with a narrower body might be required.

Clevis Pin Diameters

  • When specifying a furling system, it is generally assumed that the forestay diameter will match industry standard clevis pin diameters in the boat chainplate and the mast tang.
  • Whilst in most cases they are fine, rigging and masts get changed over time and these can sometimes be mismatched, which can lead to complications.
  • Although not required to obtain the right price or specification of the drum, it is important to double check the pin diameters before placing the final order.
  • This is also a reason why it is NOT advised to 'size up' your furling system with the hope of increased power, strength or durability: it can result in significant, hidden cost increases due to fitting incompatibility.

Deck Chain Plate & Mast Tang Style

  • Again, not necessary for the initial specification and budget stage, but prior to final order, it is important to provide information on the configuration of your bow chainplate and mast tang.
  • Chainplates come in all different shapes and sizes however, the configuration will generally be one of two options:
    • Nose (most common) - Single plate and requires a fork toggle interface
    • Fork - Double plate & requires an eye toggle interface
  • Hole diameter, orientation (fore & aft or lateral) and plate thickness / fork width are important dimensions to consider
  • Remember: Pictures are worth a thousand words - take a couple of photos, they are invaluable! Luft Tape Groove Dimensions
  • Finally, different foil sections have different groove sizes to fit the genoa luff tape.
  • Therefore you should also check/measure the diameter of your luff tape.
  • This measurement shouldn't drive the specification choice for your furler - it is just something to have in mind in terms of comparing the overall costs.
  • In most cases luff tapes will not be an issue, but if the correct furling system requires a luff tape change, this is a relatively quick / simple alteration for your sailmaker.
  • If you are changing from a hanked headsail to a furling system, you should also discuss with your sailmaker the pro's and con's of re-using or replacing your existing sail.

Armed with your measurements, and now want to explore your furling system options? Browse our genoa reefing, or get in contact with us via our genoa reefing enquiry form for a tailored recommendation.

Related Articles

Karver KJ Jammer
Releasable under (low) load combined with the reliability of a high load jammer French hardware manufacturer, Karver has been active in the French offshore sailing scene (IMOCA and offshore multihull) since its inception in 2004. Their reputation is based on developing a range of innovative products. Posted on 18 Sep
What is a top down adapter?
A tack swivel is a popular evolution of the top-down furling system The top-down adapter, also known as a tack swivel, is an increasingly popular evolution of the top-down furling system. This technique provides cruisers and racers alike, simplicity, safety and speed for the handling of loose luff sails. Posted on 12 Sep
Reefing Your Mainsail
Are you onboard with reef hooks? An ingenious addition to their portfolio, Karver's KHR Reef Hook offers an unconventional way to reef your mainsail. Originally designed for ocean racing multihulls, reef hooks are now being adopted by more and more cruising sailors. Posted on 4 Sep
Transform your sailing with a Velocitek Speedpuck
Lightweight, compact speedometer with high accuracy Speedpuck is a responsive, digital speedometer which utilises the same GPS technology as the America's Cup-endorsed Prostart. Although suitable for boats of all sizes, the Speedpuck is known to particularly flourish on dinghies and one-design keelboats. Posted on 29 Aug
Karver's new 3:1 Friction Sheave
An increase in quality with a reduction in both weight and price It's not often that developments in fitting design deliver a significant increase in quality and a reduction in both weight and price - all at the same time. But Karver Systems appears to have achieved the impossible with the new 3:1 Friction Sheave. Posted on 21 Aug
Bjarne Lorenzen interviewed: Furling Your Mainsail
Andy Rice looks at 'in boom' and 'in mast' furling Most of the time we think of furling headsails but as Bjarne Lorenzen of sailmaker Doyle O'leu explains, there are options for mainsails too. In the fifth and final post from this series, Bjarne considers the pros and cons of 'in boom' or 'in mast'. Posted on 7 Aug
Ino-Rope update
The latest in textile block performance In light of the newly updated Ino-Rope product range, we ask you to cast your mind back to 2013: a French duo - experienced offshore Mini Transat 650 sailor Thibault Reinhart and professional rigger Julien Barnet - burst onto the sailing scene. Posted on 3 Aug
New Electric Bowsprit Furler from Bamar
An option for 40-60 footers Whilst performance enhancing marine electronics - such as nke - continue to thrive in popularity, more and more people are also choosing to turn their heads towards the automatism of various sailing systems. Posted on 29 Jul
Do I need the nke Man Overboard Module?
A small, portable transmitter that automatically detects M.O.B. As the trend for performance enhancing marine electronics continues to grow, here at upffront.com we have decided to make things simple for our customers: we've crafted six, turn-key, nke autopilot and navigation packages. Posted on 27 Jul
nke Marine Electronics packages
Introducing the 'Cruise' package from upffront.com Due to nke's impressive product range, we also introduced a number of marine electronics packages crafted by Upffront.com. We created these packages to simplify the tricky world of marine electronics, and the result was six turn-key packages. Posted on 19 Jul
MBW newsletters (top)