Forgot password

Multihull biplane vs schooner

<< First  < Prev   1   2   Next >  Last >> 
  • 21 May 2012 16:33
    Quote
    Reply # 926333 on 910824
    Anonymous member
       Theres an interesting piece by Phil Corridan about {Junking Alleda }  double masting on a Iroquois cat Newsletter56 .    
  • 10 May 2012 20:27
    Quote
    Reply # 916901 on 910824
    Anonymous member
    I've just checked, and you should be able to find your drawing in 'your files/drawings'.

    I have indeed played around with the idea of a non-hinged wingsail batten that flips around its long axis, and wrote about it in issue 53, pages 20 - 21. But I have never been able to satisfy myself that such a rig could be built light enough and strong enough, with simple low tech methods (aluminium tube and rivets), or that any small gain in performance would be worth putting in a huge investment in high tech methods. 
  • 10 May 2012 19:54
    Quote
    Reply # 916875 on 916427
    Anonymous member
    Mark Thomasson wrote:

    I have not managed to find the 'drawings' directory.


    Neither do I, now.  Last time, I found it in a few steps through the menu on the left, but I must be having a senior moment.  If you give me your email address, I can send you the file.  Or you can read it at http://proafile.com/forums/viewthread/94/ or download the pdfs from the Yahoo proafile group.  I've been fishing for comments there as well.

    Mark Thomasson wrote:

    PS do you have your wing sail design on line somehwere?  I am definately thinking on those lines.


    http://groups.yahoo.com/group/junkrig/files/Aerodynamic%20junk/

    If you want the red sail shown in figures 8, 9 and 10 of that file, I still have it, though without battens.  For lack of a suitable boat (if I remember correctly, you took mercy on the boat on which I tried that sail, and gave it a good home), the sail has been packed away, dark and dry, for 12 years.  I planned to give it away some years ago, but recently found that I never sent it off.  The man never got in touch to ask what happened, so I guess he wasn't desperate to have the sail, or else he was too polite for his own good.  I can put a new address on the box.

    I also had a related idea.  Make internal battens that are teardrops near the mast, then have a long rigid part (sort of a tadpole shape, or a sewing needle with a fat eye).  The sail attaches to the batten only at the forward part of the teardrop and the aft end.  In between, it is loose.  Put flexible battens into the loose part, with enough tension that they bend the sail one way or the other.  The idea is to get some asymmetry without any joints in the load-bearing battens.  Connect the two sides of the sail with a line or two.  If the leeward bendy batten pops, it will pull the windward batten after it.  If instead you use a small stick, then popping the windward batten pushes the leeward batten out.  It's much the same idea as the red sail, but having the battens all inside instead of mostly outside the sail.

    And I wonder whether David's idea of having flipping battens in the wing really needs the crossover of both parts near the mast.  Wouldn't it be enough to bend first a symmetrical wing profile, then bend in the horizontal plane, and let the whole thing flip like in Nils Myklebust's sail?  David?

    Regards

    Robert Biegler
  • 10 May 2012 14:02
    Quote
    Reply # 916427 on 910824
    Anonymous member

    I have not managed to find the 'drawings' directory.

    (is this just me, but I do sometimes find it dificult to remember where to find things)

    Look forward to seeing your sketch Robert.

    I am sketching a junk rigged proa schooner, with overlapping sails, will post soon.

    Cheers

    Mark (from Scotland)

    PS do you have your wing sail design on line somehwere?  I am definately thinking on those lines.
  • 06 May 2012 11:47
    Quote
    Reply # 912963 on 912660
    Anonymous member
    David Tyler wrote:But since I now know you want to add something, I'll send you an "invitation to collaborate" in the JRA members files directly.

    Thanks.  I added the file "Biplane Sloop" to the "Drawings" directory.

    Regards

    Robert Biegler
  • 06 May 2012 06:10
    Quote
    Reply # 912907 on 910824
    Anonymous member

    Robert

    Thanks for posting the link, very interesting read.

    I look forward to seeing your design ideas....

    Peter
  • 05 May 2012 21:58
    Quote
    Reply # 912660 on 912436
    Anonymous member
    Robert Biegler wrote:
     I have come up with an idea for a biplane rig for a Pacific proa (with junk-style sheeting), and would like comments from people who are more than the mostly armchair sailor that I am.  Can I upload  a two page, 183kB pdf somewhere?

    Regards

    Robert Biegler
    Robert,
    Yes, you ( or any other member) can go to "Your files" in the menu, and follow the directions at the bottom of the page for enabling you to add something to the documents folder.
    But since I now know you want to add something, I'll send you an "invitation to collaborate" in the JRA members files directly.
    David.
  • 05 May 2012 13:26
    Quote
    Reply # 912436 on 910824
    Anonymous member
    Peter Scandling wrote:

    I continue to examine the possibility of a multihull. It seems that there are two schools of thought on multihull rigs with Bertrand and Pete advocating a biplane setup but others sticking to a more traditional schooner/ketch style.

    That is perfect timing for my question.  I have come up with an idea for a biplane rig for a Pacific proa (with junk-style sheeting), and would like comments from people who are more than the mostly armchair sailor that I am.  Can I upload  a two page, 183kB pdf somewhere?

    Regarding masts getting in the way of accommodation, there is no need for a biplane-rigged catamaran to have its masts on the centreline of each hull.  In fact, you would want them as far outboard as possible anyway, to reduce interference between the sails.  By happy coincidence, that also gets them out of the way of accommodation.  Boards have also been put into the side instead of the centrelines of hulls at least since the Iroquois design of the 1970s.

    You might want to read about Gary Lepak's boat Dragon Wings: http://www.duckworksmagazine.com/04/s/vintage/multihulls/index.cfm

    Regards

    Robert Biegler
  • 05 May 2012 06:18
    Quote
    Reply # 912302 on 910824
    Anonymous member

    Thanks David,  that explains why James Wharram and Eric de Bisschop used a jib....

     
  • 05 May 2012 02:04
    Quote
    Reply # 912201 on 912165
    Anonymous member
    Peter Scandling wrote:

    Can the need to 'keel' step the mast be overcome by using a stayed rig?  Assuming that a suitable location it site the mast?

    Peter

    Yes, but a stayed mast cannot be put right in the bow, whatever the type of boat, and so to get the sail area far enough forward, it's usually necessary to use a headsail. That pushes you towards the type of rig that Tom Colvin designs, with a headsail and one or two junk sails.
<< First  < Prev   1   2   Next >  Last >> 
       " ...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