Flat, hinged or cambered?

  • 28 Aug 2018 10:14
    Reply # 6642182 on 6642110
    Annie wrote:
    David Tyler wrote:Short pockets can claim the same slight advantage when replacing a batten, and I think they're a little quicker to add than webbing tabs (but slower than full length pockets). Also, they can use up more of the scraps and short ends left after cutting out the panels.
    Much easier to fit webbing tabs than pockets? I can't see why. 
    Personally, I'd claim it as a huge advantage.  I said they were easier in sails with vertical seams, where you have to send the whole sail through the throat of the machine, when sewing the battens pockets on.
    A flat sail that is made by sewing all the cloths together, and then adding the pockets, certainly does require half of the sail, to be passed through the throat of the machine, rolled up, (working from the middle towards the top and then from the middle towards the bottom). But I can't understand how adding your webbing tabs is any different? How did you do it?

    Personally, I'm glad that we've moved on from that scenario, which was hard work with a big sail. Our more recent methods, which have the common factor of adding a panel, adding whatever batten arrangements we prefer, then adding the next panel, makes a lot more sense.

  • 28 Aug 2018 09:30
    Reply # 6642132 on 461931
    Anonymous member (Administrator)

    Over the years, I have noticed that many who have made camber in their sails, this way or the other, have taken great care of progressively reducing the camber from the lowest one and upwards. Frankly, I think that is waste of time. Only my three top panels have been made flatter. This lets me use the same pattern on all the 3-5 lowest panels, and thus save time during production. This goes whether the sail is constructed with the barrel-only, the barrel plus broadseam, or with any kind of shelf-foot method. Re-using the same pattern(s) 3-4 times saves time.

    Mind you, although I only sail inshore these days, I certainly reef quite often, partly since I generally rig my boats generously, and partly because the west coast of Norway can be a windy place. Still, I have never felt ” oh, dear, I wish I had cut panel four and five flatter”  -  not for a single time. The 8% camber that I have standardized on in panels 4-7 on my small boats, is just about right for my use. It gives a good compromise between brute force and pointing angle.

    It’s a free world, so do it how you like. I just say that standardizing on one camber between 6 and 10% on the four lowest panels works well.

    Construction time.
    The sail of my Ingeborg was started 29.12.2014 and was finished 11.1.2015. Malena’s blue, cambered sail was made in exactly 40 hours (May 1994). There I used the super-quick-and-dirty amateur method A. Even the roping of it; hand-stitching on a rope-type boltrope (including a lot of splicing), took only eight hours. When that sail fell apart after 16 seasons, it was the cloth that gave up. Both the machine seams and the hand-stitching had held well.

    Arne

    PS:
    The lovely thing is that any of the known methods of building camber in the panels can be combines with Jami’s improved hinges for joining the panels at the battens. Jim C is sooo right about the internet  -  back in the nineties this info would have taken years to spread.


    Last modified: 28 Aug 2018 09:58 | Anonymous member (Administrator)
  • 28 Aug 2018 08:45
    Reply # 6642110 on 6640056
    David Tyler wrote:Short pockets can claim the same slight advantage when replacing a batten, and I think they're a little quicker to add than webbing tabs (but slower than full length pockets). Also, they can use up more of the scraps and short ends left after cutting out the panels.
    Much easier to fit webbing tabs than pockets? I can't see why. 
    Personally, I'd claim it as a huge advantage.  I said they were easier in sails with vertical seams, where you have to send the whole sail through the throat of the machine, when sewing the battens pockets on.
  • 28 Aug 2018 08:05
    Reply # 6642095 on 461931

    Credit to Roger for being the first to think of this system (unless anyone knows differently?), and to use it in a sail that is fit for purpose and satisfies his requirement.

    And then credit to Jami for taking it on a step, and reducing some of the air leakage paths, particularly in way of the mast. Whether the air leakage matters very much is an unanswerable question, without a test programme, but for offshore cruising usage, Roger has shown that it can be lived with.

    A bit of armchair sailmaking: I think I'd try making shelf foot panels, then working the straight edges of those shelves into the alternate hinge/gap format. That way, the hinges don't have to be made as separate pieces. Still time consuming, though. 

  • 28 Aug 2018 06:49
    Reply # 6642020 on 6641513
    Arne wrote:

    Howevere, here the panels have not been cut with round in them. Instead, Roger has  created the camber by making hinges of raising size towards the middle (or max camber) point of the battens. This must have been quite time-consuming, as one cannot just mass-produce hinges of one size.

    I guess I would prefer the way Jami solved it  -  quicker to do and with the same benefits as the sail on Ming-Ming 2.

    I wouldn't say quicker - one just uses the time differently. In my system the hinges can be mass-produced, but the camber must be done with a barrel-shape and/or broadseaming, whereas Roger's panels are simple and straight.


  • 27 Aug 2018 22:51
    Reply # 6641581 on 461931

    I was just reflecting on how wonderful it is to have the Internet, so we can discuss what we love, in real time, as apposed to letters and magazines which toke months to do what we can do now in a day or two.

    I attach a screenshot of Jami's new sail.

    1 file
  • 27 Aug 2018 21:40
    Reply # 6641513 on 461931
    Anonymous member (Administrator)

    Now I have been struggling my way through six YouTube clips about the reconstruction of Roger Taylor's Ming-Ming 2

    There, in Part 6, I learned to know how Roger constructed his sail. The upper three panels are quite conventional, lightly cambered panels with batten pockets. Only the lower panels are made as independent panels with these 'hinges'. However, here the panels have not been cut with round in them. Instead, Roger has  created the camber by making hinges of raising size towards the middle (or max camber) point of the battens. This must have been quite time-consuming, as one cannot just mass-produce hinges of one size.

    I guess I would prefer the way Jami solved it  -  quicker to do and with the same benefits as the sail on Ming-Ming 2.

    Arne

    PS: One can only speculate if the much bigger gaps around MM2's hinges do any good or harm to the airflow around the sail...

    Last modified: 27 Jun 2021 10:08 | Anonymous member (Administrator)
  • 27 Aug 2018 17:13
    Reply # 6640788 on 461931

    My little junk sail has split battens screwed together through the sail with two sided carpet tape on both batten halves, I can't recommend it as it's pretty obvious that the sailcloth needs to be able to shift at least a bit on the batten to set properly.

    Even not working properly it's not a bad sail.


    Bill

  • 27 Aug 2018 13:50
    Reply # 6640434 on 461931
    Well,

    fortunately I have nothing to compare to regarding the amount of work needed. As of yet I have only made two junk sails and used hinges in both of them...

    But I guess one needs maybe twice the amount of work and time (spent on batten pockets versus hinges, not the whole sail) to make the sail using this method. Let's not forget that there are some benefits too, especially with handling of the sail while sewing.

    Rigging the sail needs more work (again a guess), than a one-part sail. 

    One of the benefits is also the possibility of taking apart only one panel - for repairs, for example. Or in my Galion 22's case, probably taking off one panel for good (and save it as a spare). Of course one could sew a spare panel or two in purpose before an ocean crossing, too, and change them at sea, if need be. 

    I didn't measure the time I spent with the newer sail, and I have no good guess, either. And we have to remember, that I was also learning to understand the broadseaming at the same time. This cost time, too.

    Comparing the two sails (Joe 17 and Galion 22) is quite difficult, because the cloth is/was very different. The first was 90 g/sqm and quite stretchy, the latter 190 g and doesn not stretch (almost) at all. This was also the reason to use broadseaming.

    EDIT: I added a brief video of the Galion's sail. Lets's not discuss the still undone topping lifts and other inferior, unfinished details...

    (Off topic: what doesn't stop amazing me with these two different boats is the balance of the 500kg stud-keel/centerbord Joe 17 with my JR. I was able to sail even dead downwind with a simple sheet-to tiller steering for hours and hours. And now I struggle with the unstable steering of the Galion 22, which has a longish keel... go figure.)

    Last modified: 27 Aug 2018 16:45 | Anonymous member
  • 27 Aug 2018 10:00
    Reply # 6640154 on 461931
    Anonymous member (Administrator)

    Jami,

    Like David, I too think this 'hinge' connection between batten panels, which Roger Taylor introduced, is a strong and dependable method. Although it surely will take more time than batten pockets, both to construct and to rig first time, the work is straightforward with no particularly difficult steps. Even I could do this. The method later gives one easy access to the battens anywhere, so two battens could easily be lashed together to ‘reef out‘ any damage at sea. For a serious long-distance sail, this may well be my method of choice (..except that I am a daysailor...).

    Now I had a look at the Youtube clips of your first boat and then of the photo of your new one. I notice that you have added broadseams to the new sail. Have you any comments to the difference in the two sails’ setting or behaviour?

    Arne

    PS: About how long did it take you to construct your sails?


    Last modified: 27 Aug 2018 10:04 | Anonymous member (Administrator)
       " ...there is nothing - absolutely nothing - half so much worth doing as simply messing about in junk-rigged boats" 
                                                               - the Chinese Water Rat

                                                              Site contents © the Junk Rig Association and/or individual authors

Powered by Wild Apricot Membership Software