Sailcloth Weight

[ilikeraresteak]

How do I determine the sailcloth weight that i need. i.e. 4.5oz, 5.4oz, ect.

[Solitude]

What sail is it for? Main, Light?

[ilikeraresteak]

main on a 40' foot ketch

[Solitude]

I would think that you would be looking more around 8oz

[svTOTEM]

If your repairing an existing sail, than Solitude is on with 7 oz to 8 oz range. If this is for a new sail, than there is more to consider than material weight. I left sail design behind about 15 years ago so I'm a little rusty on the current cloth options, but for your boat you also need to look at yarn size and warp vs fill count. The choice differs for high aspect (which ketch mains tend to be) vs low aspect sails, whether there will be full battens, etc. For Dacron material, I'm partial to Challenge Sailcloth www.challengesailcloth.com.

[barnakiel]

Nej, nej, nej - you ask the sailmaker. The weight depends on sail area / sail type / wind range / cloth choice. If your area is predominantly light you may go with a lighter cloth.

8 oz. is somewhere there but do not jump - ask your loft they will recommend.

b.

[DaveOnCudjoe]

Gotta go with the sailmaker. I just put a new main on the F-31, a very powerful sail. It was made of 8.3 oz modulus dacron( whatever that is ) and it goes like a scalded cat. Dave

[svTOTEM]

Ha! How rude of me to suggest that a sailor learn a little bit about his sails. Far be it from me to suggest that the naïve consumer may get a crappy product, but I’ve seen and repaired too many crappy sails made by sailmakers that choose cloth based on price rather then appropriatness.

[DaveOnCudjoe]

I'm a cabinet maker by trade. I keep up on the latest trends and developements in the industry. If a new product or application comes along I know it first. My sailmaker is the same. I didn't let my fingers do the walking when I choose him and likewise my customers come to me based on my expertise. I listen to them and provide a product best suited to their needs and sometimes budget. They could go to Home Depot but they come to me instead. I could have bought sails made overseas for half the price but can guarantee no one there sailed around the world on Playstation. Trends in industry change too quickly for the layman to keep up, it's important to do your research but I put my trust in the experts. Having said that, the one's at Smith Barney sure saw me coming. Dave

[Christian Van H]

Originally Posted by svTOTEM

Ha! How rude of me to suggest that a sailor learn a little bit about his sails.

Dont have the slightest idea of where you are coming from, but I learned a TON from speaking to several sailmakers at the Annapolis show. There is alot more than LOA and sq. footage to selecting a cloth weight and type. High aspect? Low Aspect? High modulus? What cut? Believe me, a good sailmaker from a modern loft knows more tech stuff than we can learn reading a website...

[Solitude]

Originally Posted by barnakiel

Nej, nej, nej -

Ar du Svensk?

[bewitched]

what is an oz?

is it a country down under? a place where a wizard lives? or some ancient unit of measure perhaps?

Are we talking oz per sq. yard?? or oz per square foot???

Or are we talking sailmakers oz? you know - the weight in oz of a piece of cloth measuring 36 inches by 28.5 inches (whatever point 5 of an inch is - I thought it had to be the decimal system before it could be point something).

but surely it's gramms per m2 these days?.......

Hold on, I need a new spinnaker - three quarter oz I think, which actually weighs something around 0.8 to 0.9 of an oz (whatever that means). sailmakers oz that is, not the other one

...I think I might tell my sailmaker what I want to do with the thing and let him sort it out.....

[svTOTEM]

It’s funny how the information in these threads can go. The message about sailcloth here seems to be bring it to any sailmaker and they will tell you what you need. That’s seems especially odd when I think about the numerous disparaging remarks about sailmakers on this forum over the past few years. In a recent thread “Sail material to stay away from” people were more interested in learning about material on their own so they could be better informed when going to the sailmaker.
I see cruising as a process by which cruisers must learn about so many different things, whether out of interest or necessity. In my experience having only a single source of information on a subject ends in disappointment to often. For example, a thread I read the other day someone suggested that a mom intending to take her young kids cruising should first go see a child psychologist in order to raise a “balanced but lonely child”. Being a full time cruiser and with three young kid onboard, the message in that is so wrong; and unfortunately, it looks like the woman that posted that hasn’t been back to this site.
If you totally trust your sailmaker or rigger or diesel mechanic then you’re lucky. Learn from them and other sources. It can be confusing enough to spec out a new sail when the sail loft is just down the road. When you go cruising stuff breaks or requires maintenance all the time. If you’re cruising far from home your sailmaker won’t do you much good, but the things you learn along the way will.
Lastly, and not to be pedantic, there is no such thing as a “sailmakers oz”. The dimensions 28-1/2” x 36” are a “sailmakers yard”, and the weight of a sailmakers yard, in ounces, is the listed weight of sailcloth. I can’t fathom –ah no wait, a fathom is 6’on my charts (surely they must be using meters by now) – imagine though that the definition of sailmakers yard is useful to anyone – I know for a fact that many sailmakers couldn’t list off the dimensions of a sailmakers yard.

[Christian Van H]

Sv Totem, I'm sure you know your stuff. I agree completely with you on both the posting about kids and the sail info. If the original poster would like to speak with a very knowledgeable sailmaker that really knows his stuff, I would like to recommend Will Keyworth at North Sails Annapolis Md. I seriously believe he wont steer you wrong. As for SV Totem, nice boat! I've always loved the Stevens. I also looked up your blog, and turned green with envy once I saw you are cruising Mexico.

[bewitched]

Originally Posted by svTOTEM

Lastly, and not to be pedantic, there is no such thing as a “sailmakers oz”. .

I probably am being pedantic here - but there is:

http://www.challengesailcloth.com/pdf/measure.pdf


But does it really matter what the weight is? Today many sail manufacturers will have their own proprietary materials from which they build sails and will be much more knowlegable on the properties of those materials than even a well informed individual.

The weight of one sailmakers material is likely to vary from another's. There are therefore significant design characteristics other than weight that come into the equation.

I would argue that the pressure "window" (force per m2) that the sail is designed to operate in, is a far more relevant criteria than how heavy the material that the sail was made out of is.