Sails - Draft Stripe and Battens - what and how many?

[Roach1948]

I am about to order a sail online, and really wanted to fully understand a couple of things before I order:

What is a draft stripe and what does it do? I notice some new sails have a thin blue stripe around 5/8th of the way up the sail – is this it?

My old sail has three battens, but the sailmaker recommends 4 battens (sail same size as a folkboat’s) – I would like to know the pro’s and cons of going with four instead of three – is this a real “improvement”? Bear in mind my previous sail is from the early 1950’s….

Many thanks!

 

[Helina]

If I understand "draft stripe" correctly it's or they are ( in my sail there is three) horizontal lines to make it easier to see the shape of the sail, that the foil shape is perfect not twisted.
A fully battened mainsail is more stable and keeps it's shape better then not fully battened. When reefing the sail flutters less and and it's easier to take the sail down with lazy jacks or - bag.
Minus side is that the sail is heavier and it's heavier to lift it but in my opinnion these are minor things.

 

[Twister_Ken]

As Helina says, a draft stripe lets you see the shape of the aerofoil you've created in the sail, and where the draft in it is. If you don't tweak your sail shape, don't bother.

Four vs three battens. The role of conventional battens is to support the luff of the sail, and stop it curling, and to allow the luff and roach of the sail to project beyond a straight line from boom end to masthead, for extra sail area. Four battens (usually long, short, short, long going from bottom to top) is the accepted way of doing this.

A long batten is about 30% longer than a short batten. Neither is a full length batten, although very occasionally you'll see a sail with three conventional battens and a full length top batten. I'm sure there's a sailmaker's www somewhere that explains this better than I can.

 

[Lakesailor]

Look on the other thread on here

 

[gardenshed]

Draft stripes will help you visualise the shape of the sail. One in the top 1/3rd and one low down would be ideal.
The number and length of the battens depends on the roach that the sailmaker intends to have in the sail. Roach is the area that is behind the straight line from the masthead to the end of the boom. As said by Twister Ken, this is supported by the battens, however this is the leach of the sail, not the luff. Tapered battens are best with the thinner end on the inside. This helps give a good transition from the soft unsupported sail and avoids setting up a nasty crease that follows the inner end of the batten pockets.
Take you sailmakers advice, it doesn't sound like he is suggesting anything odd or unusual.

 

[Lakesailor]

In fact the class rules for the main show 4 battens (from the Nordic Folkboat International Class Rules 2005-2008) Doesn't matter if you are not racing, but maybe if you are selling.

 

[Salty John]

"The shape of the headboard may variate". How quaint!

 

[Twister_Ken]

>however this is the leach of the sail, not the luff.<

Quite right, I plead temporary insanity, m'lud.

 

[Roach1948]

Many thanks for your quick replies. My yacht is not actually a folkboat - juts the mainsail is the same. The draft stripe comes as standard, so I guess I will go with that. As for the battens, Roach has a small Roach so lucky I questioned it. A larger Roach could have hit the backstay and now I am down to three battens again.

 

[gandy]

I prefer battens parallel to the boom if possible - makes the sail stow neater when reefed or packed away.