In response to Graham’s post below, here is a sailplan with the mast through the front half of the hatch. The resulting mast balance of about 24%, and with only 5m battens, should ensure easier steering downwind, without having to shift the sail back and forth.
Note how much closer the CE sits to the mast on this sailplan.

Arne

( Full size sailplan under Arnes's sketches, section 7-43 )

Arne wrote:

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Graham, a quick look at that salplan makes me wonder.
Isn't that sailplan (CE) sitting a bit too far forward?
I guess I would aim for a plumb mast and then choose a sail with less mast balance, possibly with a yard angle of 65 or 70 degrees.

Arne

Thanks for your feedback, Arne.  I intend to have a vertical mast, if I proceed with this project (I am also looking at other boats with a view to selling this one, but the choices, within my budget, seem dismal), but I did not get it quite right in this concept image, which is just what Phil Bolger called a 'cartoon'.  No mathematics were involved.  However, the CE of the Cavalier 32's bermudan rig is well forward; it is forward of the aftermost small window, I think, though I have not been able to find a drawing of the bermudan sailplan that shows the CE.  The bermudan rig's mast is in line with the front half of that small window, and the rig has a small mainsail and a huge jib, like so many IOR boats of that era (it had a half-ton rating in its racing days).  People who have sailed these boats in fresh winds all say the boat drives on the jib, with the main doing little more than acting as a trim vane.  Having made a coastal passage on a Cavalier 26, I can believe this.  It became very hard-mouthed when driving to windward in an 18-knot sea-breeze.

Nonetheless, I think the CE of my drawing might need to move aft by about 300mm.  Given that this sail has a balance of 23.5%, I could easily achieve that by going back to 10% balance, even if the sail has to be redrawn slightly.  I could also use long batten parrels, and pull the tack aft to the mast in light winds, letting it go forward again in fresh winds, when these boats develop weather helm.  Arion's junk rigged sistership, Minke, did this, to ease the helm, but I chose to put Arion's CE 300mm further forward, which gave me a balanced helm on all points of sail.  The advantages of having someone else try things first!

I do like the 23.5% balance, though, and another option might be to put the mast at the front end of the coachroof, where the forehatch is now, and move the hatch further aft.  This would actually make installation a lot easier, as there are already two structural bulkheads fore and aft of this position, and I would not need to do contortions  working in the forepeak!  In fact, the more I think about it, the more I like it!  I will do another cartoon tonight and post it here soon.  My approach is to put the CE in the same place as it was in the bermudan rig, especially with cambered sails (PJR recommended a little further forward with flat-cut sails). 

It's wet and cool here (it seldom gets really cold in Mooloolaba), so I've been playing with ideas for junk rigs. If I go cruising again, it has to be under junk rig, so the options are to find another boat project, or convert Mehitabel. I was leaning towards another, smaller boat, but am now playing around with the idea of converting Mehitabel. I'd have to replace the backing plates on the keel bolts, and get the bolts surveyed first, but if they are sound, it might be the best way forward. Anyway, I am very comfortable living aboard. I don't particularly like balsa-cored hulls, but it seems solid, and the Cavalier 32s have a reputation as well-proven and capable sea boats. Here's my initial sketch for a 38 sq m sail, based on a drawing by Arne Kverneland. If I went ahead, I'd get the final drawings and sail developed by Paul Thompson, the excellent junk rig sailmaker who built my last junk sail for Blue Moon.

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