Frankenboat/Wishbone

Discussion in 'Sailboats' started by revintage, Apr 23, 2019.

  1. revintage
    Joined: Nov 2016
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    revintage Senior Member

    Getting closer! Seems I should start up the lawn mover, instead of playing, though;).

    0538E4A1-8F66-4174-8642-605D7419264F.jpeg
     
  2. revintage
    Joined: Nov 2016
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    revintage Senior Member

    Built the daggerboard today. The 1250mm Windknife profile with NACA0009 270x25mm was to thin for my taste. I pressed a 1" alu tube through it (hard work) to make it 0011. Didn´t press the tube the whole way through to make the profile thinner at the lower end, made it 23mm wrt 30mm for the rest of the profile. It remains to fill the ends with MS polymer adhesive.

    I have studied the UFO wishbone rig and looks intriguing, might try that concept, after having evaluated and learned to use the present.

    The People’s Foiler: A Design Brief on the UFO Foiling Catamaran - Professional BoatBuilder Magazine https://www.proboat.com/2017/03/design-brief-peoples-foiler/

    Earwigoagin: Seen at the 2018 Sailboat Show: the UFO http://earwigoagin.blogspot.com/2018/10/seen-at-2018-sailboat-show-ufo.html
     

    Attached Files:

    Last edited: May 20, 2019
    Doug Lord likes this.
  3. revintage
    Joined: Nov 2016
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    revintage Senior Member

    Small step forward. Made a prototype plate of 12mm HDPE for adjusting daggerboard angle and to fit the new daggerboard foil profile to the daggerboard box. Settled for a three point solution, one bolt forward, two rear.

    2E4032B4-FDCA-493C-AE95-1A91961DBE5D.jpeg E435DCD7-670B-4517-A79E-7298EB28235B.jpeg 5CB94886-F1CF-4787-9797-5089F34AFA7D.jpeg ABC98E16-5C50-4898-9F93-9499BF886143.jpeg
     
    Last edited: May 22, 2019
  4. revintage
    Joined: Nov 2016
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    revintage Senior Member

    Closed hauled and close reach worked fine, but outside of that the low clew interferred with the leeward automatically lifted wing. The almost 70 year old youth also found the foot a little low in tacks&gybes. Decided to cut the sail to lift the clew 18”, thus loosing 0.4sqm. First image is the trim I added with a forward pointing spreader to control excessive mast bend and the second is photoedited to get a reality check of the cut. Will sew next week and try out again when I return to the summer house mid August. Made the rear tubes of the wings longer to let the slack 2mm Dyneema lifting lines go completely free from the leeward side of the sail on a broad reach.
    mastbend.jpg cutdownskothorn.png A7142056-B696-4EC2-AB1F-C561895C5DF2.jpeg 3BEFEDF8-E341-429D-994A-F57E4AA542D9.jpeg 4A8561D5-71ED-4C75-B96D-FC4EDDE362A5.jpeg
     
    Last edited: Jul 26, 2019
  5. trip the light fandango
    Joined: Apr 2018
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    Location: Rhyll Phillip Island Victoria Australia

    trip the light fandango Senior Member

    That is neat, I'll be having a serious look at my leach/clew, that is an extra extra dimension for me to learn about, an extra knot even cruising is worthwhile, W17 Designer has a well written article about this on his home page. thanks for the reminder. I like the dagger board plate too.
     
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  6. revintage
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    revintage Senior Member

    Grew really tired by the mainsheet going along the sail foot, getting caught in every jibe and tack, although I could have added a tunnel. Whats wrong about transom sheeting(with an automatic ratchet block at the clew and a single block with becket at the bridle) like in the modified image?

    transomsh.png
     
  7. gggGuest
    Joined: Feb 2005
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    gggGuest ...

    Transom sheeting is viable enough, but the ratchet block really needs to be the last block otherwise its a bit awkward to release.
    An alternative might be to run your mainsheet along the wishbone with a fairlead or block at the widest point to keep it clear of the sail.
     
  8. revintage
    Joined: Nov 2016
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    revintage Senior Member

    Edited:

    Should be no problem with release with a automatic ratchet as they are loadsensing, ie no ratchet function when you release.

    Can probably use the ratchet at the bridle instead like in the sketch, problem solved. Think I will go for 3 parts instead of 2. Or should I maybe turn it upside down?

    Below is the 25gr Harken 2159 I now have ordered.

    Will try things out when I return to the summer house a week from now, returning with the recut main sail.

    Harken Sailboat Hardware and Accessories https://www.harken.com/productdetail.aspx?id=42255&taxid=7723

    rat.jpg sheet2.png sheet3.png sheet4.png blazerecut.png
     
    Last edited: Aug 18, 2019

  9. revintage
    Joined: Nov 2016
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    Location: Sweden

    revintage Senior Member

    Have now tried the three part sheeting but have decided to go for two part. Anyway transom sheeting worked great and the modified sail is now clear of the wings.

    A problem though when sailing from my shallow beach out to deep water, is that the daggerboard interferes with the mainsail foot. The daggerboard has far to large area and shall be cut down 25cm giving an area of 0,2sqm. If needed I will also add a few centimeters to the lower end of the mast.

    blaze2.jpg
     
    Last edited: Sep 4, 2019
    tlouth7 likes this.
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