Hi Slieve,

Thanks for your comments. I chose the Wanderer as something stable to take the kids out in that I could still move on the shore. So far I like it a lot.

Looking at the photos there are two thoughts which come to me. In an ideal world, with and infinity thin mast I would make the slot width zero. As the real mast gets thicker I feel the slot should get wider, to let the air flow past the mast, so I suppose I think of the slot width to be proportional to the mast diameter. Thin mast narrow slot, fat mast and wide slot. You have a fairly thin mast but to my eyes the slot looks very wide, which may (or may not) lose some of the benefit of accelerated air flow. (If I sound rather vague here it's because I'm not sure but it is a thought).

Yes - the wide gap is an accident :-) I made the jiblets from the wrong layer in QCAD, then had to figure out how to make a sail that would work without changing much.

I'm not sure of the effect, but something in me says that a wide exit from the jiblets might help a bit. However it wasn't intentional!

The other thought is that as you get the rig settled down it is more important to remove all diagonal creases from the jib panels than from the mains, as it is the airflow over the cambered jibs that does the majority of the useful work. Creases in the jibs distort the camber badly.

The yard angle for no creases in jiblets and mainlets is (unfortunately) slightly different, but I will play and see what happens.

I don't see telltales on your jibs, but they are a great help, and you'll probably find that with them streaming you'll get your 'best to windward' performance. Keeping the jibs pulling should be the key to best performance.

Yes - these are on the todo list but I haven't had time to fit them (and probably won't this year). It has all been a bit more rushed that I would have liked.

Cheers

Martin

Hi Scott,

Yes - I'm happy with the sail based on my limited (light wind) experience. I did spend some time playing with various ways to cut the panels and concluded that barrel cut using my spreadsheet and a few tweaks would work as well as anything else.

I'm not sure barrel cut would work well with a fabric that wasn't stretchy on the diagonal.

The panels are barrel cut. The fabric is stretchy on the diagonal so creases tend to disappear. I spent some time experimenting with fabric, sticks and sticky tape. There is a bit of extra fabric (1% of panel width) on the sides in front of the point of maximum camber plus an extra 5mm in the centre of each jiblet luff and this appears to do the trick.

The jiblets collapse when too close to the wind, although it is possible to pinch using the mainlets alone.

The colour scheme is (of course!) based on the JRA logo :-)

The design is actually a merger of the Johanna and Poppy sail plans. I was actually trying to build something more Johanna-like but started cutting out jiblet panels based on the wrong layer in QCAD. Oops. A hasty redesign followed to figure out a way to use the panels I had already made and this sail is the result.

First sail today in my converted Wanderer dinghy :-)

For those who don't know the Wanderer is a smaller Wayfarer - 14' instead of 16' - which makes it much lighter and easier to move around on land.

Pictures here: https://junkrigassociation.org/Sys/PublicProfile/29417059/PhotoAlbums/103651223

Very light winds today, but enough to fill the sail and get her moving nicely. Seems well-balanced and delightful to sail. A big relief - this sail has been put together against a deadline which means lots of corners were cut - so I wasn't certain everything was actually going to work.

I've now got a boat - a Wanderer. This is a smaller version of a Wayfarer - 14' instead of 16', much lighter and thus easier to handle onshore. Back to the calculations!

Currently a wooden mast looks optimal. I'd be making a wooden topmast anyway so I'll see what timber is available locally.