Dennis, Ash

I already have Otto, my homemade wind vane of Bill Belcher’s OGT MkII design lying around. This worked well on an earlier boat, but will be a number too small on the unbalanced rudder of the IF. My preferred adaption of that wind vane would be via a separate (retractable) auxiliary rudder.

However, as I have no serious deep-water sailing in mind, a wind vane is not high on my to-do list. I must be happy enough when the new rig is operational. Next step then is to do small additions to the interior (galley, table, w.c. and maybe a heater, some day).

But one thing at the time  -  many projects have run aground because of too many plans..

Cheers, Arne

Arne,

I was wondering if you were going to implement a wind vane steering system on your IF.

If so, will you be considering Jan Alkema's Rudder Head Mount idea?  The IF would seem to an appropriate hull for that very interesting design.

If this has already been discussed to death, please just point me to the thread.

Dennis

Dennis,

I guess the view about what is a sensible or “appropriate” sail area, differs a bit among JRA members. I have tended to make my sails a bit bigger than average by aiming for a SA/Disp of 20 – 25.

My point is that we need a big sail area to get enough power downwind without a spinnaker (my first reason for going JR was in fact to do away with the sp.). Besides, in strong winds we can reef the JR quickly, and then it is only the weight and windage of the mast that counts. Now I just measured the mast of an original Bm-rigged IF to be 10.75m above the wl. That mast will reach just below the tip of the yard of my planned JR. Ingeborg’s mast is only 9.5m above the wl. In other words, although the JR’s 35.2sqm gives a SA/disp. of 21.1, I claim that it will be a perfectly sound rig  -  or if anything, a bit on the modest side  -  I must be getting old...

So, you are right, the lower aspect ratio JR I have chosen here will require a lower mast and I can thus safely pile on a bigger sail area than the Bm rig.

Cheers,
Arne

When boats grow above 5-6 tons, there will be other problems, like restricted deck space or restricted muscle power to hoist the sails, so one must accept lower SA/disp, down to 17, 15 or even 13.

Arne,

We are coming to a consensus.  The manufacturer comes back with 130 lbs for 33' x 3/16" x 6" tapering to 3" (FYI $1050 USD)

This would compute to 2.7% of IF displacement

The same manufacturer comes back with 200 lbs for 1/4" wall as opposed to our calculated 175 lbs.  Either way too heavy for the IF, but it may work if I get the Frances. Even if we buy the higher weight, it would only be 2.9% and considerably stronger.

My immediate focus is to see if this Frances can be gotten at a low enough price.  I will keep my eyes open for an IF also.  As I said, they are rare on this side of the pond.  Rarer still is the slightly larger Marieholm 26.  I will also be looking at a couple of nearby Contessas to evaluate the complexity of dropping a mast through the forward hatch.

I look forward to reading your article about the hybrid mast

Hi Antoine,

No, the making of of my Ingeborg’s sail will follow the same lines as that of making the sail of Broremann, Edmond Dantes , Frøken Sørensen and Chapter 5 of TCPJR. On the other hand, I am midway in a write-up about the hybrid mast. I guess I will just add it to Chapter 6 about the (wooden) mast.

As for batten dimension, I haven’t decided yet, but must do so pretty soon since I use batten pockets in my sails.

Checking the lists of available tubes here, I guess I must choose between 35 x 2mm (0.59kg/m, Mb=243Nm) and 50 x 1.5mm (0.64kg/m, Mb=404Nm). The alloy used is 6060-T6 (150MPa).

Arne