Trouble making a sail?

[sq_waver]

Dear DN'ers,

Has anyone ever tried making their sail? I tried this winter, but found it very difficult to put draft in the sail because the sail cloth has seems to have zero flexibility(in other words, it' very difficult to sew a straight edge to a curved edge with out a lot of wrinkling). I ended up with a very flat sail.
So I'd like to ask
1) Is there a trick to adding draft to the sail that I've missed?
2) Should all the seams be at the batten lines? Does that make a stronger sail? Or is that for looks only?
3) Is the luff of faster sails curved or straight?
4) How much draft does a typical sail have?

Regards,
sq_waver

[rnlivingston]

Most sailmakers use a basting tape to hold the edges together while stitching.  Sailrite.com sells it and it works well to hold a curve.

Roger Livingston
DN 4568

[Geoff Sobering]

Making a good sail from "first principles" is almost impossible.  Probably the best way to start is by getting an old sail (that's not too blown out) and making patterns for each panel from it.  The best way to do that is by ripping apart the seams, but you can probably do "OK" by tracing the panels.  Remember that the accuracy in the panels is probably on the order of 1mm, so you want to be very careful when you're making your patterns and cutting/stitching the duplicate.

Another excellent way to get started is with a kit from Sailrite.  I notice they list the DN on their website: http://quotesys2.sailrite.com/ShowAd.aspx?id=4323

Roger's advice about using double-sided tape to hold the panels together while you're stitching them is very good (I don't know of any sailmakers that don't use it).  It also allows you to more carefully align the panels together (remember that 1mm tolerance) than you could if you were just trying to feed the two pieces of cloth into the machine.

In general, Sailrite is a good resource for sail-making supplies.

Just out of curiosity - what kind of sewing machine are you using?

Cheers,

Geoff S.

[DN 805]

You will want to make sure a DN sail complies with the DN specifications, particularly with respect to the sail cloth being used.   The Class specs assure that appropriate quality cloth is used so that the sails are durable, as well as efficient.   You're fooling yourself if you use cloth that does not comply with DN specs, because your sail will not be as durable as one of approved cloth.  And don't forget windows, they are essential for safe sailing.

Seams integral with batten pockets are labor efficient.  The required spacing of pockets takes into consideration the width of the cloth and the efficiency of labor to build the sail.

After you buiild a sail you'll realize that  a sailmaker ekes out a small profit only if he is both extremely proficient and efficient.  He needs to know the characteristics of the cloth and other components of the sail,  the flexibility of the mast, the wind and ice conditions, as well as having the skill to assemble the sail.

It isn't a simple task. 

DN 805

[sq_waver]

Dear DN'ers,
Thanks for the answers. As for a few responses

"Most sailmakers use a basting tape to hold the edges together while stitching.  Sailrite.com sells it and it works well to hold a curve."

I bought my materials from Sailrite and did use a basting tape on the seams. (but, see below)

"Just out of curiosity - what kind of sewing machine are you using?"

I'm using a home sewing machine which with a little work extended the width of the zig zag.(It's a cam machine).

"It isn't a simple task."

I agree with that. I have some experience recutting sails for boats and doing repairs. This is my first attempt at a mainsail for a DN. But I was not expecting the 6.8 oz cloth for the DN to be so stiff. I found it very difficult to put any draft in the sail with out wrinkles. Try cutting a curved edge in a piece of paper and tapeing another piece of paper with a staight edge to it. You end up with a wrinkle and or a bowl shape (the draft) and that I found very difficult to sew.
Anyway I'm going take some some of your suggestions and see if I can measure an old sail. But I guess part of this class is making stuff so I think before next winter I'll make a new mast and try again at making a better sail. (and maybe better runners and a new plank and............)

Good sailing
Regards,
sq_waver

[Ken Smith]

You said>> But I guess part of this class is making stuff so I think before next winter I'll make a new mast and try again at making a better sail. (and maybe better runners and a new plank and............

Now you got both the right idea and the fever....