Annie Hill wrote:I have been unhappy with the way my boom was positioned and a crease that kept appearing in panel 5 (from the top).  I am still experimenting here and feel that I am going to be shot down in flames, but I have reverted to hauling the forward end of the boom into the mast with a standing boom parrel.  In addition, I have added a standing luff parrel from boom to batten 7 and between battens 5 and 6.  These are now hauling the luff back to where I want it to be whether the sail is set fully or reefed and also seem to be reducing the loading on the luff hauling parrel. 

Very interesting, Annie.  Blondie used a standing luff parrel on Pilmer, first setting up a temporary standing boom parrel to haul the boom into the desired position then setting up the luff parrel.  He then dispensed with the boom parrel.  When he dropped the first panel the boom moved a little forward until the now horizontal luff parrel took up the role of a boom parrel.  He felt that moving the sail a bit forward when reefed was beneficial to balance but of course his sail was flat and our cambered sails are different beasts and it may be that you need both to control your creases.

I did fit a couple of standing luff parrels to Arion last year, from the boom to the lowest batten and then another one from that batten to the batten above.  I found, with the way my battens want to go forward so aggressively, that it caused a lot of friction when lowering the sail but they worked well otherwise.  It is always fascinating to hear of the various experiments going on in the hunt for the perfect arrangement.  My set up is still far from perfect and I am looking closely at Arne's ideas at the moment as he seems to have got his HM sail working well.  I might try a Fantail sail one day when I have money and energy to spare.

David Tyler wrote:

Arne Kverneland wrote:  My experience with this is that the throat and yard parrels definitely offload the HK parrels with 90%+, but the HK parrels are still useful in stabilising the luff as the boats (Johanna or Edmond D) are pitching against a headsea. From the photo of that F7 testsail of Ti Gitu it appears that they were sailing on flat water and I fear that the battens 4-5 may well start sliding back and forth in a seaway, but I could well be wrong here as the sheets may keep the panels steady.

Arne

Arne, 

This could be a significant point of difference between the behaviour of a long-luff, parallel-batten sail, and a short-luff, fanned batten sail. I notice no tendency for the lower battens to slide fore and aft in a seaway.

I agree. Ti Gitu's tall sails are quite different animals from Tystie's low AR sail. Even the two sails of my boats; Broremann's with AR=2.15 and Johanna's with AR=1.87 behave differently.

Arne

                                                        Stavanger, still Friday, just

                                 Paul Fay about Ti Gitu

Paul Fay’s article was very interesting. His finding that it paid to shorten the boom (and in his case also the lowest batten as well) and also his conclusion that the correct use of a throat hauling parrel and yard hauling parrel is Step Number One to get the sail to set right, confirms my own findings here. I also notice that he now has tested the sail successfully without HK parrels thanks to the use of the two "top" parrels. My experience with this is that the throat and yard parrels definitely offload the HK parrels with 90%+, but the HK parrels are still useful in stabilising the luff as the boats (Johanna or Edmond D) are pitching against a headsea. From the photo of that F7 testsail of Ti Gitu it appears that they were sailing on flat water and I fear that the battens 4-5 may well start sliding back and forth in a seaway, but I could well be wrong here as the sheets may keep the panels steady.

Arne