by GreenLake » Wed Sep 28, 2016 5:06 pm
I have that setup on another (non-DS) boat.
The halyard should be something that is rather less stretchy. There's quite a choice in rope that you can use. If you want to stay with New England Rope, then have a look at their Endura Braid, for example. Sta-set is rated as "medium stretch" whereas Endura Braid is low stretch. (The ratings are from the APS website and should allow a quick comparison).
The boat I have uses a wire halyard, but some of the modern ropes can mimic wire.
The halyard ends in a block, to allow it to be tightened using a 2:1 purchase, which is powerful enough to allow setting of the tension. Importantly, there's a "catch" mounted on the mast that prevents the halyard from moving up the mast beyond the distance needed for adjustment. This is very important, as the mast will be unsupported, should the halyard come loose entirely. (The halyard fits the catch, but the eye at the end or the block would not, making sure that there is positive support for the mast. You tension the halyard manually and insert it in the catch, then later tension it more as described next).
At the bottom of the mast is a cleat, to which is knotted a secondary line. That one is run up through the block on the halyard and back down to the cleat on the mast, creating a 2:1 purchase.
The system works really well and is easy enough to operate that you can adjust tension on the water. Of course, you can simply set some tension appropriate for the expected wind conditions and leave it at that.
Putting a turnbuckle in line with the furler has two disadvantages. First, there would have to be room for it, without needing to shorten the luff of the sail. Second, it would increase the separation between foot of the jib and deck. Ideally, you want the jib to "sweep" the deck, so less power is lost from the pressure difference between front and back of the sail equalizing by air flowing around the foot of the sail.
The kind of mechanism I describe is not super tricky to set up or use. You should get used to it quickly and thereafter not notice it, unless you want to learn how to adjust it on the fly when the wind drops or increases.
~ green ~ lake ~ ~