Anonymous wrote:

Anonymous wrote:

What about having a closed pocket at the luff and just tensioning at the leech, or vice versa?  Is it better to make plugs for the batten ends or just use ring bolts or similar to tie into?

I have these closed pockets at the leech of my sail, to prevent the battens to catch the sheetlets. They are closed  with webbing, and I have used wooden plugs at each end of the aluminium battens. At the luff I have webbings with velcro to tension the sail. So far I'm pleased with that system.

With the mast ordered I have started to look at yard, battens and boom. I am planning to use aluminium tube, From PJR there is an example of batten size of 22mm x 3,2mm used for Pilmer which I have used as a guide. I have chosen a bigger dia tube for the yard in view of the weight it carries, and a slightly bigger dia tube for the boom so that it doesn't bend with the pull of the tackline.   I am thinking of:

Yard      40mm x 5 or 3mm wall thickness

Battens  22mm x  3.25mm wall thickness

Boom     28.5 x 3.25mm wall thickness

Do these sizes seem about right?

I am interested to understand how the battens are tied into the sail. It seems they are often tied/tensioned at both ends. What about having a closed pocket at the luff and just tensioning at the leech, or vice versa?  Is it better to make plugs for the batten ends or just use ring bolts or similar to tie into?

Thanks for any comments/suggestions, Jes

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Anonymous wrote:

I've found this...looks like it could work.  It's 7m tall in total, 3mm wall thickness, tapered starting 2.8 m from the bottom, from 145 to 76mm dia, so would need a small extension according to Arne's sketch, which I think is 7.7m in total. I don't know how the access door would affect strength.  I could weld it to seal it and strengthen that area.

- Jes

Jes, it would be a pitty to buy a mast weakened by any holes. Even if welded shut, those areas will be where fatigue appears first.

It might work for you to directly contact that supplier, and ask them if they would sell you the raw mast - of a production stage, where they did not cut any holes yet. At least, that worked out when I bought the mast for Ilvy. It was cheaper, too.

Cheers,

Paul

Anonymous wrote:

The Corribee has a smallish rudder. This hi-balance JR brings its CE quite close to the JR mast, which again means that the CE will sit close to the boat’s centreline when sailing downwind. This should help the rudder to cope.

Just an idea.

Arne

PS:
It looks to me that the superstructure of the Mk 2 and 3 are very similar, so I used a Mk 3 version here.

(Hi-res diagram in Arne's sketches, section 8, photo11)

Bonjour

Mingming has bildge keels and a skeg in front of a small rudder rather forward. It has a natural tendency to sail strait....

There is not a great weather helm, the helm is very light but sailing headwind, the helm has to be pushed windward about 30°, which is enormous and I suppose that the ruddder must be almost stalled !

It could be interesting to suppress the skeg and to move the rudder to the transom.

It is diffucult to tack.

Eric

NOTE FROM WEBMASTER:  This active and useful thread was moved from Buy/Sell forum to Technical forum at the suggestion of a the original poster and another participant.  See separate new thread on Buy/Sell forum re acquiring a mast. Cheers.