The first test sail done, and I couldn't be happier!

The wind didn't favor me, though - on the other hand I had easy time getting to know the sail, the ropes and the light wind performance of the rig. A lot better than the BR, I would say, thanks to the enlarged sail area and light fabric.

Here is a short video of ghosting in an almost non-existing night wind at about three a.m.

I have no HK parrels and a very simple THP, but I think the sail sets nicely. It seemed to do so also in the daytime, when I had more wind for a short time. 

You can see here my experimental construction of the sail. It's Arne's Johanna-type sail with AR of 2.15. I have cut the barrel-shaped panels the usual (Arne's) way, but instead of batten pockets and sewing the panels together, I made webbing hinges. They are very short, just enough for the battens to slide in and the hinges to turn around them. 

Edit: To be clear: all of the hinges are the same size/length. The camber is formed by the cloth form, not the hinges (as opposed to Roger Taylor's hinged sail).

I chose this experimental method because it seemed to fit to my workflow better and because I had a wild guess that it might make it easier for the sail to set nicely and with less wrinkles. Part one worked fine, but I'm not the one to say if the hinges have something to do with the setting or not.

Somehow I seem to have hit the balance spot on. The tiller is very light and the directional stability is excellent compared to the BR at least in light wind. Beginner's luck!

I hope to get a grip on stronger wind next time.

(Note: This was my first sail ever in a JR boat. I don't have tho words to describe the overwhelming feeling I had, experiencing the silence and unstressed feeling of the rig - not to mention seeing that a sail that I have sewn myself actually works.)

So far so good - I'm very happy for this!

I would also like to thank everyone here for your tips and support, especially Arne and David. I would never have succeeded without you.

I would not worry too much about that, at least not before the boat has been tried. Of course, if one makes a drum skin from this cloth and it gets wet, the result will look very slack. However, if you already have a sail with baggy panels, I think  it will make much less difference between wet and dry. Go sailing and see for yourself.

Arne

PS:
I base my reasoning above on my fiddling with my chain calculator to produce cambered panels:
It takes very little round to achieve the equivalent of 1 or 2% camber. On the other hand one must add a lot of round to increase the camber from 8 to 10 % (about 50% more round). Frankly, I think you will hardly notice the difference.

Jami, I've been finding that the red cloth stretches quite a lot. I made my wind vane sleeve from it, and it's taut when dry, goes quite slack and cambered when the rain pours down (as it's doing right now),  and then goes taut again when dry. I hope this isn't going to produce any ill effects in your sail.

Sneak peek of a test hoist here:

http://www.junkrigassociation.org/resources/MemberAlbums/36745719/Joe%2017%20junk%20rig/Julle_junk1.JPG

No THP yet, only YHP lead through the tip of the yard to let it stand high enough for the test. A measurement error on panel two, but looks like sail to me!

Thank you, both. I can't really tell you how much your help is appreciated (and needed, for that matter).