Making My Own Sail

[osirissail]

As barnakiel says, just go look at sails either in lofts or on boats and examine the stitching - zig-zag is how seams are put together. If you use straight stitching you are setting up a "paper perforations" situation where the sail will easily rip down the line of stitching.

[Jim Cate]

FWIW,

In a dinghy sail, the likelihood of a seam failure because of straight vs zigzag stitching is not a factor. If you have a machine that will do a reasonably long straight stitch there will be more than adequate strength in the seam and the cloth, and there will not be noticeable adverse affects from "puckering" if the machine is adjusted well. The use of transfer tape (a sort of double sided tape used to assemble seams before stitching) makes it pretty easy to get things aligned before stitching with either type of stitch.

For the beginner sailmaker, the real advantage of zig sag stitching is that it is easy to rip out when you make the inevitable mistake. On my early attempts I did a LOT of ripping out! The extra needle holes were never a factor in those sails. Getting the shape right was!

Finally, Sailright used to sell a series of pamphlets on the design (from scratch) of various sails -- mains, jibs, kites, storm sails, etc -- and on the use of home machines to accomplish the sewing. Not cutting edge even then, but I was able to design and build useful sails for rather low investments. I don't know if they are still available to buy... mine ain't for sale!

Cheers,

Jim

[Entlie]

Having recently undertaken a repair, I learned from a helpful sailmaker not to zigzag unless absolutely necessary because it leaves too much thread exposed to UV deterioration.
Have fun!

Entlie
Sailing Catamaran Sunspot Baby

[senormechanico]

Sail thread will eventually rot from UV.
IMHO, zigzag stitching in sail fabric is the best way to go, but tension settings are more critical than straight stitching.
I no longer use sail thread for my trampolines or sails.

After having to resew my trampolines every couple of years, I finally bit the bullet and bought a big spool of Tenara thread, otherwise known as GoreTex.
It is guaranteed for life against UV damage, and it's really strong stuff.
Two years later, and it looks like the day I sewed them. Best $129 I ever spent.
BTW, I sewed them on my Bernina 180, (rotary hook 9mm zigzag) home type machine.
(I service sewing machines for a living)

sjsewing

[Daddydion]

Was just looking at the machines and one does straight but the other spears to do zig zag ( based on the foot). They are stored and am in the process of getting them out. The singer is a foot trundle and only does the straight but my cousin swears it will do zig zag. After more research I am leaning toward zz. I just ordered a book on sail making dimensions and math that my engineer friend suggested (he got me into sailing) and have just ordered the plans for my "boat". My ultimate goal is to be living aboard a boat with my wife in ten years and kiss the civilized world behind. Between sewing and mechanical ability I might even be able to prevent going broke in the process:0)

[osirissail]

I have had small sailmaker sewing machines and now a large Brother sailmaker machine which cost me over $2K plus all the spare parts for it. However, it had "paid for itself" a dozen times over by allowing me to repair my sails and make all my canvas for the boat over the last decade.
- - But sewing on your own machine sailcloth or even canvas (Sunbrella, etc.) has been and I believe it, called a love/hate relationship. The process involves some serious "pounding" and stress on the machines. They get out of alignment frequently and you need to know how to realign your machine. I can go sometimes through a whole project for a week with only one broken needle and then on the last day go through a half dozen needles. So don't expect the process to be as simple as sewing clothing.

[Jim Cate]

Originally Posted by osirissail

I have had small sailmaker sewing machines and now a large Brother sailmaker machine which cost me over $2K plus all the spare parts for it. However, it had "paid for itself" a dozen times over by allowing me to repair my sails and make all my canvas for the boat over the last decade.
- - But sewing on your own machine sailcloth or even canvas (Sunbrella, etc.) has been and I believe it, called a love/hate relationship. The process involves some serious "pounding" and stress on the machines. They get out of alignment frequently and you need to know how to realign your machine. I can go sometimes through a whole project for a week with only one broken needle and then on the last day go through a half dozen needles. So don't expect the process to be as simple as sewing clothing.

Look, this chap is talking abut a sail for a dinghy. Something like 4-5 oz cloth and skimpy corner patches. Any decent (non-plastic) home machine will happily sew this material. I used an old Singer that I bought very second hand, gave it a "tune-up" as described in the Sailrite manual, and it did all that I asked of it. Patches I hand stitched... no big deal, even on the storm jib I made for my Yankee 30.

Cheers

[Daddydion]

Ok, have the dimensions, now I just read in a boat building book that small sails such as mine can be made of "tyvek" and seams "sewn" with a strip of tyvek double backed tape used for outdoor carpet. Any thoughts?
Catch the wind

[osirissail]

For a dinghy sail, weight is a major factor so the use of "Tyvek" or other very thin, very strong, very light sail cloth makes a difference. And yes, because of the thinness of the material normally a double sided tape is used to first put the panels together and then you sew them together through all three layers. Be sure to use sail thread which is usually polyester UV thread or if you can afford it the Tenara super long life thread.

[GorillaToast]

First, get a copy of "The Sailmaker's Apprentice" by Emiliano Marino, then down load this free sail design program.

Sailcut CAD - Sailcut

I haven't made a complete sail yet, but I did add 14 reef patches, and 2 sets of patches for reefing clews to my mainsail, using an older (one with metal gears) Singer sewing machine I got at the thrift store for $25. Plus I made a Sunbrella sail pack and various other canvas projects.

Don't be fooled into thinking you have to have a "walking foot" machine, or attachment for your old Singer. Just pull the material thru with your left hand at an even pace as you sew.

And yes, sails are made with zig-zag stitches, at least the Doyle Sails that came with my boat have predominately zig-zags.

[Pete R]

Originally Posted by Daddydion

Ok, have the dimensions, now I just read in a boat building book that small sails such as mine can be made of "tyvek" and seams "sewn" with a strip of tyvek double backed tape used for outdoor carpet. Any thoughts?
Catch the wind

I made a Tyvek/carpet tape sail for an Escape Rhumba dinghy. The plastic hull failed before the sail did. It was noisy, though.

[Shanaly]

daft question: how do i reach the middle of a big sail to machine sew a burst seam?

[forsailbyowner]

I made sails for my dinghy by cutting down old throwaways. I set mine up as a gaff rigged sloop and it goes to windward quite well.

A couple of people mentioned nylon thread. Not a good thread for life in the sun.

I wouldn't pay the big bucks for sail cloth. Something like topodessey which is an acrylic coated polyester would seem a cost effective alternative.

I've always wondered about the necessity of zig zag stitching for sails. Once a seam is taped with permanent fusing tape and triple stitched is there really any seam stretch? I've been repairing my sails for years and have never had a seam rip along the seam line. I use multiple rows of long stitches to minimize "perforated paper" effect which is inherent in both sewing methods.

I've read several books on sailmaking and design. I remember a beginners book mentioning, on your first attempts make the body of the sail flat and build the shape in on the luff and foot. There's a lot of room for error trying to place the CE by building the shape into the panels and without a lot of practice, or cad help it often ends up badly.

I will be building my next suit of sails out of topgun. Its cheap, strong and I've seen sails built from it before. 11oz polyester with acrylic uv coating.

[osirissail]

Originally Posted by Shanaly

daft question: how do i reach the middle of a big sail to machine sew a burst seam?

It isn't easy - you have to fold and roll and bunch up the sail material being careful to keep the area being sewed smooth and not under any tension from the rolled/bunched/crunched up part of the sail. You may spend several minutes wrestling the whole sail into position in order to get that one little 3 inch or so section of stitching into the proper position.

This is where the "arm length" or depth of the sewing machine makes a big difference. The machines where the arm length is short are less desirable than the machines with really deep arm length. However, the longer/deeper the arm length the more the machine is vulnerable to having the needle and base flex out of alignment. Which is why the "old" cast iron and heavy machines are worth finding versus the new lighter machines.

[daddle]

You can certainly build a reasonable sail yourself. Sounds like you have a suitable background. Sailrite is the best source of info. Like most engineered things, sails are not designed from scratch, each is based on earlier sails. It's an incremental thing. Like aircraft parts there is nothing simple about them.