I build this Spinnaker from plans I drew up using a formula from a book Spinnakers - Their Design and Construction (http://www.sailrite.com/Spinnakers-Design-Construction ) I purchased from www.sailrite.com. This spinnaker is 20ft tall and 10ft wide. It's made from ripstop nylon I purchased from Joanne Fabrics www.joannefabrics.com. Click the link, Adventures, to find out how flying the spinnaker actually worked out.
The drawing at the left shows the layout of the panels. I used Windows Visio 2003 to create scale patterns.
Shown are the final assembly sizes. Remember each part must be built slightly bigger to allow for seaming.
I find using MicroSoft's Visio 2003 Professional is invaluble in doing most of my Project layouts. www.microsoft.com
Here I am lofting the first two sections of the upper panel.