It is an interesting project.  I would say that the battens look like they may be set up for Aerojunk already.  Their shape and configuration is similar to those on Blossom, a previous BOTM.  If that is the case, the sail becomes relatively simple to sew, as it is all flat panels, although it does need careful reinforcement.  The battens themselves will give you some idea of the dimensions of the sail, as a starting point, but a really clear side-on picture would give Arne and others a chance to look at balance, and the height of the mast and number of battens will give some clues to panel height.  It will be a fun puzzle!

Good luck,

Mark

Ailsa.
I look forward to learning about the position and the LAP of your mast.
The simplest rig for the existing mast in that position is probably the Split Junk Rig, SJR.
That only requires straight, simple battens, and the production of the sail seems to be doable, although I have never tried...

Arne

Ailsa wrote:

I recently purchased 'Obelix', a Westerly Centaur junk rig project boat, here in Cork, S W Ireland. The hull and engine are sound, there is a solid-looking freestanding mast, and some wishbone battens. The internal fit out needs to be done, but as a graduate of IBTC I don't have any worries there. The sail plan will be a bit more of a challenge, I'm currently thinking Aero Junk, but open to other ideas.

I really enjoyed single-handing a 30 foot Freedom ketch in the North Sea, but I was a bit younger then and I would find those big wishbones a bit heavy these days. The wraparound sails gave a good aero foil shape, so I would like to get close to that with a junk rig if possible. All advice and suggestions gratefully received!

I'd say that my wing sail is a good match to that requirement, with the lightest, simplest junk-rig-based battens that I have been able to devise in a good airfoil shape that surrounds the mast:

https://junkrigassociation.org/Sys/PublicProfile/
2757889/PhotoAlbums/97381300

https://junkrigassociation.org/Sys/PublicProfile/
2757889/PhotoAlbums/101152027

Except that the mast in Obelix appears to be quite well aft, and the existing wishbones seem to be assembled onto the mast by opening their after ends, then the after of the two crossbars, indicating a lot of balance area; and my wing sail has the absolute minimum of balance area.

Anyway, I think more detailed analysis will have to wait until you're able to investigate the original rig more fully, establishing the position and height of the mast.