Please select your home edition
Edition
upffront 2018 Generic 728x90

Lengths of Sheets and Halyards

by Diego Sosa, Upffront 8 Aug 2018 01:00 PDT
Why is it imperative to have the correct lengths for sheets and halyards? © upffront.com

We have previously discussed taking care of ropes, but, how long should these ropes even be? As previously mentioned, ropes are an essential element of your rigging system, and optimising your running rigging lengths is important.

Why is it imperative to have the correct lengths for sheets and halyards?

Obviously, too short a sheet or halyard does not get you anywhere. A rope that is too long increases the chances of getting tangled, adds to the overall weight of the boat and it's just a waste of money!

Length Calculations and Formulas

You have chafed through a sheet / halyard, on your holiday, and need an emergency replacement shipped to you. How long should your new line be?

Standard sail-maker I.J.P.E. dimensions are usually the most commonly available data to work from. The following diagrams and formulas will then help calculate the most appropriate length for your ropes.

Don't worry, this isn't complicated maths, or rocket science. However, please do bear in mind that these are measured in metres, thus all rope lengths (results) are defined as such.

P: Mainsail hoist length
E: Mainsail foot length [Image 1]
I: Height of the forestay above deck
J: Length from mast to forestay

Y: Distance from halyard winch to mast
X: Distance from genoa winch to mast
Z: Height of boom above deck
L: Boat length
Ig: Height of Inner Forestay above deck
Py: Mizzen hoist length
Ey: Mizzen foot length

© North Sails


Example

IJPE Formula applied to Beneteau First 40 (source: Sailboatdata.com)

L= 12.24m
I= 16.05m
P= 15.57m
J= 4.60m
E= 5.39m

Main Halyard 1:1 (winch on mast) = 2.1 × P + 2
Therefore = 2.1 x 15.57 + 2
Main Halyard Rope Length = 34.70m

Gennaker Sheet = 2.5 x L
Therefore = 2.5 x 12.24
Gennaker Sheet Rope Length = 30.6m


© Sailboatdata.com

Safety Margin

Most of these formulae add an extra one or two metres, which translates to a little more 'extra rope' as a 'safety margin'.

Conclusion

Rigging systems must have accurately measured and cut ropes to function properly. This then enables sheets to control and halyards to hoist sails efficiently. A general rule of thumb to calculating the length of halyards is to use the 'vertical' P / I measurements (height of the mast), while calculating the length of sheets then uses the 'horizontal' E / J, plus overall boat length.

To learn more about running rigging, check out our free guide at upffront.com

Related Articles

Cousin Trestec Constrictor - A Textile Rope Clutch
Based on the 'Chinese finger trap' so is kinder to your ropes At some point in our lives, we have all experienced the vice-like grip of the 'Chinese finger trap'; when pulled, the cylindrical, woven braid is designed to contract and constrain the finger. Posted on 18 Feb
Choosing the Right Winch
An educated choice will save you from unnecessary spend Choosing a winch can be daunting. The main decision criteria may be size or power ratio, but style, speeds, material and grip are also of a consideration. That's without going into powered options (electric/hydraulic). Posted on 13 Feb
Basic Running Rigging Terminology
Dekanewtons explained If you are looking at upgrading your running rigging, before you delve into the manufacturers catalogues there are a few key terms you need to understand: Single Braid, Double Braid, Rope Strength measured in daN (Dekanewtons). Posted on 8 Feb
Would you trust Dyneema with your lifelines?
80% lighter and 4 times stronger than traditional wire Lifelines are typically made of wire, however, as the sailing industry modernises, more and more people have been converted to the use of synthetic composite lifelines, such as Dyneema®. Posted on 4 Feb
A Guide to Mooring Lines
Arguably, one of the most important pieces of kit? Arguably, one of the most important pieces of kit onboard your boat is a mooring line; it's all well and good having a great boat, but if you can't safely secure it at the quay, harbour or pier then you're in real trouble. Posted on 30 Jan
Facnor FlatDeck Genoa Furling System
Fresh in at upffront.com with a unique webbing feature It's no surprise that the Facnor FlatDeck is the newest addition to the Upffront website: it's the latest in genoa furling innovation. We are excited to launch Facnor's revolutionary furling system on our website: the Facnor FlatDeck Furling System. Posted on 28 Jan
Why and When You Need a Code Zero
Andy Rice interviews Bjarne Lorenzen of sailmaker Doyle O'leu In a previous blog, Bjarne Lorenzen talked about the exciting new performance cruiser, the 39BEN built by Bente in Germany. While the sail plan will develop over time, the code zero was one of the first sails to go into the inventory. Posted on 25 Jan
What is a sailing dogbone?
They have been around for centuries, now re-engineered A dogbone is a small, light, dual tapered rod, which can simply and efficiently connect lines together. As the name suggests, its shape is comparable to that of a 'dog bone', where the middle section is tapered, and the two ends proportionally wider. Posted on 21 Jan
Nick Black Talks Main Halyard Locks
Final discussion in the series on lock systems for yachts The final in our series on lock systems for sailing yachts, Andy Rice talks to Nick Black of Rigging Projects about mainsail locks. Reef locks have taken off in a big way in recent years, mostly because clew loads have become higher and higher, Posted on 14 Jan
Introduction to Winches
With recent innovative features and performance improvements Although the fundamental mechanics of winches have not really changed over the years, there are some innovative features and performance improvements which have appeared in the industry in more recent years. Posted on 11 Jan
YY.com app (top)