what size spinnaker :(

[sand sailor]

hey robert

can you recommend a good book on sail making my wife wants to give it a go compaired to the things she does now this should be a good project for her

 

[RichH]

LP ... more.

Sand Sailor -  "Sailmakers Apprentice" is a good place to start. Most sails today are desigtned by CAD/CAM programs; but, if you want to totally hand-make your sails do a websearch for 'broadseaming'. Jim Grant of Sailrite used to publish such a book using the on-the-floor-sail lofting-methods. There are shareware computer programs that will give you the individual offsets ... the easiest is to have someone with such a high-end program and VERY large scale printer/laser cutter do the cutting and marking for you ... then all you're left with is the 'drudgery' of putting it all together. I started our many years ago with kit sails from sailrite.com (before the days of computers) and worked my way up from there.... although for a complicated (radial, etc.) cut its best timewise to have someone plot and cut it all for you. With CAD/CAM youll hardly ever make a mistake in the shape. Robert: http://www.phrfchesbay.com/esspec2.pdfhttp://www.cruisingdirect.com/LP_Measure.htmhttp://rorcrating.com/ir2000/irc/interpret/headspi.htmhttp://www.wb-sails.fi/news/SailPowerCalc/SailPowerCalc.htmhttp://dan.pfeiffer.net/boat/ratios.htmhttp://www.ukhalsey.com/LearningCenter/encyclopedia/encyclopedia4b.asphttp://en.wikipedia.org/wiki/Genoa_(sail)http://www.usedsails.com/measuring.htmhttp://www.secondwindsails.com/measurement.phphttp://www.ukhalsey.com/sails/howtobuysail/buyasail5.asphttp://www.profurl.com/us/choix/tambour.htmhttp://www.porpoisesailing.com/measure.asp... this will get you started. just google LP + sail been a PHRF admeasurer? .... thats the probable reason why PHRF is dwindling, the PHRF measurers still dont understand the difference between J and LP

 

[Robert Gainer]

A good book

RichH has recommended Sailmakers Apprentice and he’s picked a good one. It’s worth reading even if you don’t want to make a sail.Good luck and all the best,Robert Gainer

 

[Robert Gainer]

RichH, did you read the links you suggested?

RichH,Did you read the links you suggested? The very first one uses the IOR formula I suggested and defines everything the way I said it was defined. Nowhere does it say spinnaker and LP in the same paragraph. Am I missing something in that reference?The second link defines LP in headsails and it’s exactly what I said. It all starts with J and this time spinnakers and LP don’t appear on the same page.The third link is the first thing that has LP and spinnaker in the same sentence. It’s a part of the British racing rules defining which is which. And it doesn’t say a spinnaker has an LP it says if it has an LP it’s a headsail.The fourth link, well it’s late and I am getting tired. What am I supposed to see on this page? It’s a cute java script to calculate sailarea.Do I need to look at any more links? Do any of the other links describe a spinnaker using the LP as a dimension? Look, you can do things anyway you want but it won’t change how the industry works. I didn’t write the rules and I certainly can’t change them just because you want to have it your way. I don’t see any reason to continue this. I think its one way and you disagree. Fine, my world will keep spinning and the sun will rise in the morning. I am sure things will be fine for you also. Good night,Robert Gainer

 

[NewportVic]

Sandy ... Before you set your wifie up ...

think about how hard it is to cut fabric with a three dimensional built in curve to it. I was told a couple of days ago that a major maker of sails has his sails sewed in Asia ... but makes sure to cut the pieces on computerized equipment here in the states. Apparently the sewing isn't the hard job ... trying to match the curves is.The real test is to get a three quotes on a Spin ... and compare the specs ... 10 to 1 all three will be different luff vs foot. Unless of course they are OEMing them from the same source.Now boat cushions ... that's a do-able thing.In any case, if you don't really want to race competively ... old spins are fine. And when set adequately ... you can have lunch while they fly.Vic "Seven"

 

[sand sailor]

my wifee wanted to try

until she read this thread you guys scared her half to death she said the interior is hers the rest is mine!!!

 

[r.w.landau]

Sand sailor, Just do it!

Heck all you do is some broad seams and if they don't work, you cut them out and resew.This is the fun part! If you are not racing who cares. If you just want to sail, design it your self. These guys can be pretty hard.If you can locate or measure spnnaker that some you know has, Look it over and just go to it. The plus about a spinnaker is that it is light and will capture air that your heavy genny doesn't.Heck, copy your 150 genny in nylon and fly it as a light air drifter.r.w.landau

 

[Alan]

I agree with r.w.

If you're not racing, go for it and just do it. If the shape isn't perfect, who will ever know??...and you'll have fun flying it knowing that YOU made it!! ;D

 

[Robert Gainer]

Go for it

Let me start out by saying I am not a sailmaker I am a sailor, designer and boatbuilder. I don’t enjoy sewing and find the hand work tedious and boring. I do have a singer 107W1 industrial machine and some sewing tables. I have setting dies, nicopress tools, swaggers and rigging vices. And I have well over thirty years experience with them. I have worked with sails but most of what I have done is repair work on replica sails and very old sails. I do a lot of handwork because it needs to be done and I am the only one on staff who can do it. After a lot of years owning a shop that designed, built or repaired lots of sailboats I now work for a museum and teach boatbuilding while building replicas.Now having said that, I want to add that sailmaking is simple and if you can sew and follow directions you can make a sail. A lot of terms get thrown around like broadseam when people get together and talk about sails but commonly the terms are misused and just make people nervous and force them to think it’s complicated.A broadseam is just a technique to put some shape into a sail. It works by changing the amount of overlap the panels have when you sew them. If you are making a mainsail you can also cut a curve into the luff and foot to add extra fabric which adds shape when you put the curved edges on a straight spar. The headsails are also shaped the same way. A spinnaker has too much shape to be made with broadseaming. In a spinnaker the individual panels are shaped and the overlap for sewing is constant. All the shape comes from the shaping of the panels. It’s not hard to make the shape. There are well known rules for designing the layout of a spinnaker. All of this is covered by books on sailmaking. There are also some software packages that help with laying out the panels. If this is something you think you would enjoy go for it and try to make a sail. It’s a popular hobby for some.Just because this is a contentious group of people I need to add a disclaimer. Sailmaking has changed over the years and some sails are now molded or shaped as one homogenous layer on forms. As far as I know no spinnakers are made this way but a lot of sails are now made this way. I also know fabrics have changed and cotton and flax have fallen out of favor and even Dacron is being replaced by other materials. But again we are talking about spinnakers not a high tech something else.All the best,Robert Gainer