Hi, Jami, 

Slieve McGalliard had done a good write-up here on the website on the broadseam method he used to construct his sail.  

On the left hand side column on the "Home" page, select "Junk Information, Public Domain Files, Slieve McGalliard"  

There you'll find a good writeup with illustrations on the logic, construction and sailing of a Split Junk Rig boat.  

Using this information, I've built a small split junk rig (10.5sqM) for a Wayfarer dinghy.  I also used Slieve's method to build camber into the main panel.  But used a sheeting angle of 0 degrees and a camber of 8%.  

I've sailed it 3 times so far and Slieve's broadseam method has worked very well.  Both the main and jib panels have set well when filled with wind, but I haven't finished setting up the sail properly to get the best out of it. No wrinkling along the battens.  Also discovered some boat problems on the hull (which hadn't been sailed for many years) which I need to rectify over the winter and start again next spring.  

There's no reason though, why Slieve's method wouldn't work very effectively for an regular balance junk sail like you had on your Joe 17.  

When you get your head around it, it is probably no more work than Arne's method and no wrinkling along the battens.  

Also, I asked a few questions on the forum along the way under "Split Junk Rig, constructions details" on the details of construction, which Slieve very kindly gave comprehensive answers to.  

Regards, Dave D.

Davd,

Is the lens method explained somewhere in detail, preferably with illustrations? I don’t seem to find a proper tutorial of any sort.

I have noticed that there have been numerous comments on darts and wrinkles having to be included/dealt with on cambered sails that are sewn with the cambered edge sewn to the batten pocket.

I wondered if anyone has considered/tried sewing the batten pocket into the middle of the cambered panel and then sew the cambered edges together midway between the battens?

As I see it this would mean that the panel distance along the batten would be shorter than the distance where the cambered edges were sewn together. This would give a natural fullness to the sail with no darts needed or wrinkling along the batten, and the batten pocket would be very easy to sew if the panel was folded and it was sewn at an appropriate distance from the folded edge. A half panel would be needed at the head and foot in order to complete the sail.

Has anyone any thoughts on this suggestion??