Well after 5 weeks of sewing & cutting in every available free moment La Chica's new sails are finally made. Can't wait to splash her and get to try them. Not to long now :-)
I have posted a few photos and a .png of the sail plan in the album under my profile. Here's an easy link to them
Sail Photos
A few points may be of interest. Unlike most western junk rig schooners (but like many traditional Chinese junks) the geometry of the two sails is slightly different. This occurs because the sails have differing amounts of balance. Playing around with stick models (and experience gained from Aphrodite) has shown me that balance and yard angle are related. That is, less balance - steeper yard angle, more balance - shallower yard angle.
If you workout your sail geometry bearing the above in mind, your sail will essentially fall into position without to much trouble.
The head of the foresail has two panels because three were to small and simply did not look right while two panels on the main gave panel sizes that were just to large. The resulting look while slightly unusual does not look to bad to my eye.
The sails are made from Marchem "Mustang" (used to be know as "Topyssey") which is around 8oz to the yard. I have now made sails from Odyssey, Mustang and Top Gun.with Mustang proving to be by far the most pleasant to work with. It is better behaved than Odyssey as it is a great deal less stretchy and being lighter than Top Gun makes it physically easier to handle. The sewing machine also seemed to like it and it did not pucker in the same way that Odyssey tends to (you can minimize that by using lots of foot pressure).
The sails were built using the "shelf foot" method simply because I now have a lot of experience with it and because it suits my work space. The method also gives good control over the shape. Of all the methods that we currently use, the "shelf-foot" probably comes closes to WYSIWYG which is a plus in my eyes.
The camber profile is pretty much that shown in Slieve's write up on his split rig. Entry angle is around 8 deg with maximum camber at 35%. The sail would have been easier to make with a shallower angle of entry but one of the advantages of getting the camber far forward is that it also moves the CE forward and I want that. La Chica has a full keel along with a deep forefoot and that has made getting the CE as far forward as possible a necessity.
To avoid having to pass the whole bundle through the sewing machine I made the panels up individually and then joined them up and put the batten pockets on as per Arne's method 2. However the leach and the luff where built up using classical sail making methods. Simply because I need these sails to go 40 000 odd miles with hopefully the minimum of attention.