Alternative catamaran rigs for self build? Becoming more self sufficient

Discussion in 'Multihulls' started by Mark Stevens, Aug 30, 2019.

  1. Mark Stevens
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    Mark Stevens Junior Member

    Great thanks, would a tiki 26 rig be sufficient for a prout 27 or a bit small? Thanks
     
  2. Rumars
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    Rumars Senior Member

    I really dont understand your ideea. What aspects can you not service or replace on a conventional bermuda rig? And what aspects of the junk do you want to use? Without an unstayed mast junks and wingsails are compromised.
    Working out the problems on a small scale does not always function because on the bigger rig you have different forces. So while on a small cat boltropes are ok on a big cat you need at least sliders if not better. The Wharram "Wingsail" is a good example. Bigger ones than on the Tiki 30 often get converted to conventional hardware because the wet fabric of the pocket clings to the mast making reefing difficult. But you can always divide the sailplan and go schooner or ketch.

    The new sailplan for your cat should at least match the existing sail area if not better.
     
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  3. Mark Stevens
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    Mark Stevens Junior Member

    Does a wharram cat not have stays? Wingsail with stays uncompromised.
     
  4. Mark Stevens
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    Mark Stevens Junior Member

    There have been many junk rigged boats that have used stays, they use a main with a near vertical yard.
     
  5. oldmulti
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    oldmulti Senior Member

    Mark I am making an assumption about the displacement of your Ranger 27 (or is it a 31). Its supposed to be 2600 lbs but after seeing the structure I will bet its about 4000 lbs when sailing, so I will use that number. The Ranger has a righting moment of 17,000 ft lbs. A Tiki 30 has a righting moment of 26,400 ft lbs. A Tiki 26 has a righting moment of 17,000 ft lbs. Your choice. The Tiki 26 masts are 7.5 meters high and can be 127 mm x 3.5 mm aluminum tube with 600 x 3 mm aluminum inserts top and bottom. Wood masts are the same diameter with 19 mm walls. The stainless steel rigging wire is 4 mm 1 x 19. I have seen on the web details of the gaff somewhere. Hope this helps.
     
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  6. Mark Stevens
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    Mark Stevens Junior Member

    Thank you for your positive feedback! My Ranger is a 27. I would be happy to use the Tiki 26 as a model for the rig. We can only get 5m Ali tubes in England, but previously I have got to the desired height by inserting a 6 stave Douglas fir top mast, so would do the same again. Do you know where I could get a sail plan for this type of sail? All the best, Mark
     
  7. Rumars
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    Rumars Senior Member

    Wharrams "Wingsail" is nothing more than a high aspect gaffsail with a mastsock. It has little to do with what people normally understand under wingsail. But if it fits your desires go for it.

    As for a stayed junk, where is the benefit if you can not let it out and need to use specialized downwind sails? Quicker reefing I mentioned, anything else?

    But you still have not answered, what is your actual goal? Do you want to be able to repair the rig alone in the jungle without tools?
     
  8. Mark Stevens
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    Mark Stevens Junior Member

    The junk offers alot more than just quick reefing. It speads the loads of the sail, reduces wear of the material, extremely easy to make. You would be able to let the sail out if you use running back stays.
    My actual goal is to be able to make and service my own rig. Alongside employing a more low tech approach removing Chandler's and sailmakers from the equation as much as possible.
    Yes repairing my sail myself does sound appealing, however why I would be alone in a jungle without tools evades me! Is this a German perception of someone who wants a simpler approach to their chosen sport?
     
  9. Rumars
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    Rumars Senior Member

    No it's not some sort of german perception it is an example of formulating goals. So your goal is to remove the need for chandlers and sailmakers. Fine for me but this brings the question of what are you willing to sacrifice to get this features, and how far are you willing to go. Accepting running backstays is such a compromise, you give up easy manoeuvers. Maybe you only sail with a crew and this is no problem, that's for you to decide. So please formulate what is important to you: speed, handling, weight, durability, price. What is allowed: modern purpose made sailcloth, modern ropes (I mean dyneema and Co., but you can exclude polyester if you like), winches, furlers, etc. Are you willing to learn traditional sailmaking and rigging or is that to much to ask.
    Every sailplan is a compromise you just need to know what you want. Getting a bermuda (or gaff if you like wharram) to low tech just means going back in time. For example: mast and boom go from aluminium to wood. You can make it yourself but it will need regular attention (varnish, paint). Gooseneck gets changed to boomjaws and sliders to lacing or mast hoops. On a cat you can even go boomless. Full battens get partial battens or even battenless. If you don't want to use modern sailcloth it's possible, but you have to use some old time sailmaking techniques and accept the durability problems.

    Without some realistic formulated goals and compromises I will just say use a flat cut crab claw made out of polytarp or cotton duck on wooden spars with supermaket ropes. That is about the lowest you can go for "low tech approach removing Chandler's and sailmakers".
     
  10. oldmulti
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    oldmulti Senior Member

    Sailrite - Fabric, Canvas, and Sewing Machines Since 1969 https://www.sailrite.com/Tiki-26-Gaff-Mainsail-Kit Mark, the web site gives details of materials etc and dimensions. The attached give an idea of the sail plan. I cannot find a full sail plan of the Ranger 27 but I did find the Ranger 31. Work out the centre of effort of both and see if there is reasonable alignment. If so OK otherwise you may have to change the relative size of main and jib to maintain the rigs balance. I hope it helps.
     

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  11. Mark Stevens
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    Mark Stevens Junior Member

    Fantastic, thanks for your help!
     
  12. brian eiland
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    brian eiland Senior Member

    You might have a look thru these photos and subsequent discussion on A-framed "Catbird Suites'
    WishBone Sailing Rig https://www.boatdesign.net/threads/wishbone-sailing-rig.1999/page-11#post-484935

    I think his website was taken down some time ago after he sold the vessel, but there may still be some info on the internet
     
  13. brian eiland
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    brian eiland Senior Member

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  14. Mark Stevens
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    Mark Stevens Junior Member


  15. Michael_P
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    Michael_P Junior Member

    Like it was already mentioned earlier I agree, that an oceanic lateen is rather easy to build and also powerful. I am using it on my DIY-catamaran with an A-mast. I added a small fore-sail on a bow-sprit, because without it was strongly weather helm. The fore-sail also eases tacking enormously.
    Here you can find two videos of my boat:

    one, that I filmed by myself at about 4 bft:


    in this video you can see more of the rig etc:
     
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