Page 101 of 101 FirstFirst ... 5191100101
Results 3,501 to 3,524 of 3524

Thread: The outrigger and proa thread

  1. #3501
    Join Date
    Dec 2011
    Location
    North East England
    Posts
    1,295

    Default Re: The outrigger and proa thread

    Quote Originally Posted by Dusty Yevsky View Post
    Im sure others will be along soon to discuss the fine points but the gist of the matter is:

    ama to leeward generally is faster because the craft doesn't heel as much, but the iakos and everything else needs to be carefully engineered for strength without weight, resulting a more difficult and expensive build

    ama to windward generally slower unless careful constant balance is maintained by the crew. The boat can be built much easier and much lighter. Pacific proas are considered to be the most boat for the buck

    Are you considering a proa or a tacking outrigger?
    For Small proas I would say the opposite is the case and for a 20 foot proa the ama to windward is the fastest.

    The crew is such a large percentage of the total weight and can be out towards the the ama, the ama can be flying (or practically almost) and there is only the vaka (main hull) in the water. In reality there are platforms to windward and leeward on most trackers and crew can generate same righting moment both tacks.

    Don’t go reinventing the wheel, look at Gary Dierking’s Boats and buy his book, unless you have visions of some carbon fibre speed machine
    http://homepages.paradise.net.nz/garyd/Tamanu.html

    there is also a great tacking proa website with links to lots of designs http://www.tackingoutrigger.com/index.html

    I do think a tacking proa would make a good raid boat, not sure the best way to row / paddle for long periods

  2. #3502
    Join Date
    Sep 2015
    Location
    Whangarei New Zealand
    Posts
    592

    Default Re: The outrigger and proa thread

    Quote Originally Posted by CWeath View Post
    Question about amas. If one were contemplating sailing the Texas200, where the wind is predominately over the starboard stern, what would be the advantages/disadvantages of the ama being to windward or leeward? This would be on a boat less than 20 feet. Discuss. Thanks.
    IMO, too small or too short an Ama is not much good if there is any chop to contend with..... for smaller Size tacking craft, this pretty much ak's for a configuration close to a catamaran. But treacly depends a lot on the sail rig you have in mind.

  3. #3503
    Join Date
    Feb 2006
    Location
    Pennsylvania
    Posts
    8,243

    Default Re: The outrigger and proa thread

    Ama to windward is the time-tested, proven and superior setup.
    -Dave

  4. #3504
    Join Date
    Oct 2002
    Location
    Coromandel, NZ
    Posts
    270

    Default Re: The outrigger and proa thread

    I have hiking seats on both sides of my outriggers now. This enables you to un-weight the ama to leeward until it is just skimming the water. I now cannot detect any difference in speed between the tacks. Ama to leeward does allow for less concentration by the sailor whereas having it to windward requires your full attention. In regards to the Texas race where you will need to eat, drink and navigate over a long day, I would rather have the ama to leeward.
    Gary

    ort side,

  5. #3505
    Join Date
    Sep 2015
    Location
    Whangarei New Zealand
    Posts
    592

    Default Re: The outrigger and proa thread

    Quote Originally Posted by John B View Post


    I'm pretty sure thats the boat we saw there last year. That video is from a few years ago and unfortunately he has since passed away . We met his brother, Alifretti.
    I thought I had put photos of it here , but perhaps there's more than one thread on the subject.
    anyway..







    The Pacific runs on panga / longboats with yamaha enduro motors and 2 stroke premix at the pumps on bigger islands. But on Fulaga they don't have many of those , day to day transport is a rotomoulded kayak, an old glass fizz boat paddled out for shellfish and octopus gathering, a yellow rotomoulded 16 ft or so boat that washed up over the reef , from Tonga or a bigger cruising boat( a gift from the sea), they have very little.
    That outrigger boat goes out fishing in the lagoon a bit, just paddled.

    Thanks for posting of these pics John B, the one of the mast up in the shed rafters shows the crucial addition of a halyard sheave, which clearly shows how rig technology effected rig development in the Pacific.

    Look carefully at the the way the yard is pushed up by the mast ( in the video clip of the canoe sailing), rather than being hoisted by a halyard.

    Capt Cook has failed to recognise the significance of this specific change that occurred when the Tongan canoe design changed from the tacking Tongiaki type to the shunting Kalia type,athough, any forked masthead allows use of a halyard.
    Whether it was in fact the Tongans who initiated the change, rather than the Fijians, is not something that Cook ever considered, and in any case the forked masthead truck is an ancient South Pacific feature rather than a Mironesian one, which points to origins of this vital feature in the Southwest (New Caledonia or Vanuatu/New Hebridies), instead of Micronesia.

    The Tongan Tongiaki tacking double canoe used the forked mast truck to push and prop the yard up ( similar to the way the video clip above shows).

    When a canoe is double ended and configured for shunting, then swivelling of the yard on a halyard is a simple thing. But when the canoe is not built to change ends ( as in the case of the Tongan Tongiaki), the forked truck supporting the yard, must surely have been an added complication to inhibit rig rotation into shunting configuration......without radical remodelling of the rig platform
    Cook thus chose to interpret this scenario as one that apparently 'proved' the invention of shunting, during his time in the Pacific (when the Tongiaki gave way to the Kalia and Ndrua shunters).
    Based on Cook's assumption, just about every so called expert on Pacific sailing canoes holds to this flawed theory, however,
    In truth, shunting is as old a concept, as is the canoe ( a double ended dugout, either an outrigger or double hull).
    Last edited by Lugalong; 08-27-2018 at 07:57 AM.

  6. #3506
    Join Date
    Sep 2015
    Location
    Whangarei New Zealand
    Posts
    592

    Default Re: The outrigger and proa thread

    Quote Originally Posted by Gary Dierking View Post
    I have hiking seats on both sides of my outriggers now. This enables you to un-weight the ama to leeward until it is just skimming the water. I now cannot detect any difference in speed between the tacks. Ama to leeward does allow for less concentration by the sailor whereas having it to windward requires your full attention. In regards to the Texas race where you will need to eat, drink and navigate over a long day, I would rather have the ama to leeward.
    Gary



    ort side,
    Sure Gary....... might as well make that Ama slightly longer and more voluminous, to provide that bit more easing of demands( on concentration and ballast shifting) when under a press of sail.

  7. #3507
    Join Date
    Sep 2015
    Location
    Whangarei New Zealand
    Posts
    592

    Default Re: The outrigger and proa thread

    As the mass on the w/ward hull or the press of sail increases, so does the demand on buoyancy characteristics of the ama (when it is kept to lee).

    keeping the big hull to lee, provides more diagonal stability for carrying of either weight or sail.

    This is an old controversy....resolved by either hanging as much mass on the shroud and outrigger/ama structure to w/ward, as provides the required mass to power your chosen sail rig.
    Otherwise... use the w/ward ama to float more stuff ( like hulls connecting structure,providing deck space and means to carry a tender/ floatable toys, motors, cargo, and creature comfort things, like a cabin).

  8. #3508
    Join Date
    Feb 2007
    Location
    Waterbury, Connecticut
    Posts
    2,042

    Default Re: The outrigger and proa thread

    I agree with Gary regarding the Texas 200: ama to lee (providing it is voluminous enough) is best. Those can be long exhausting days, for 5 days, and attention can indeed wander. -- Wade

  9. #3509
    Join Date
    Jun 2011
    Location
    Vancouver, Canada
    Posts
    14

    Default Re: The outrigger and proa thread

    I'm putting my little proa LOL up for sale:
    https://vancouver.craigslist.ca/bnc/...743770574.html
    Pick up in person only.
    Last edited by cpcanoesailor; 11-12-2018 at 09:53 AM. Reason: updated CL ad

  10. #3510
    Join Date
    Apr 2009
    Location
    Merritt Island, Florida
    Posts
    64

    Default Re: The outrigger and proa thread

    I busted the iakos on my Ulua about 2 years ago. Finally have some time to get going again. In his Outrigger Canoe book, Gary Dierking specifies 5 laminates for the solid wood cross beams. He states that you can use cedar for the 3 middle layers, but to use something harder for the outer “skins”. In my excitement 5 years ago, I only used cedar. They held up great until I decided to go out in too much wind with WAY too much sail.


    I have cedar that I’m milling up, and am trying to decide between some Douglas fir at the local yard, and some mahogany I have. Any thoughts for the outer laminations? What would you use?
    Jon
    Building: Ha! I have Toddlers. Just able to get back in the shop and start fixing.
    http://flsail.blogspot.com/
    Built: PK78 dinghy, EasyB canoe, Ulua

  11. #3511
    Join Date
    Jun 2007
    Posts
    651

    Default Re: The outrigger and proa thread

    Quote Originally Posted by flsail View Post


    I have cedar that I’m milling up, and am trying to decide between some Douglas fir at the local yard, and some mahogany I have. Any thoughts for the outer laminations? What would you use?
    I'd go with the Doug fir. Mahogany can have some tricky grain that might be problematic under loads. Look for the straightest grain DF. I'd also consider Ash for the top and bottom skins. Ash is a very tough, bendy wood that will hold up to a heavy load. Iceboat planks are made with outer skins of ash for this reason and are subject to loads far greater than any softwater spars. Ash will rot if left out in the elements but wouldn't be problem for a properly stored day-sailer. Around these parts Ash is also half the price of VG DF.
    Last edited by Dusty Yevsky; 10-19-2018 at 01:46 PM.

  12. #3512
    Join Date
    Feb 2007
    Location
    Waterbury, Connecticut
    Posts
    2,042

    Default Re: The outrigger and proa thread

    Yeah, douglas fir or sitka spruce for the whole thing. Why construct akas that you have to worry about? They are rather fundamental for an outrigger :-) If anything is to be overbuilt, or 'err on the safe side,' let it be the akas. -- Wade

  13. #3513
    Join Date
    Jun 2007
    Posts
    651

    Default Re: The outrigger and proa thread

    I experienced outer skin failure on an iako that was built with only spar grade sitka spruce. Failure in an Ulua could quite quite traumatic as the ama is an integral element of hull stability. I would stick with a tough wood like DF or ash. I replaced the outer skins with ash and have had no problems since.

  14. #3514
    Join Date
    Jan 2012
    Location
    downward bound
    Posts
    3,159

    Default Re: The outrigger and proa thread

    ash skins holds up to more banging and abuse than the spruce, ime. doug fir isn't much tougher than sitka.

  15. #3515
    Join Date
    Sep 2015
    Location
    Whangarei New Zealand
    Posts
    592

    Default Re: The outrigger and proa thread

    Using a hardwood as an outer laminate, at least on the top and underside, is a good thing. Covering same with a resin glass skin also helps to protect where there is pressure from compression in contact with gunnels or ama connectives.

  16. #3516
    Join Date
    Feb 2007
    Location
    Waterbury, Connecticut
    Posts
    2,042

    Default Re: The outrigger and proa thread

    Quote Originally Posted by Lugalong View Post
    Using a hardwood as an outer laminate, at least on the top and underside, is a good thing. Covering same with a resin glass skin also helps to protect where there is pressure from compression in contact with gunnels or ama connectives.
    --- Reminds me of a conversation I had with someone who was friends with the Gougeons (of West System epoxy) and was keeping up with many of their materials studies. They had studied (in their lab) the effects of glassing, the result being, that on parts glassed only on one side, there was noticeable damage to the unglassed side during flexing. The narrator flexed and crinkled his fingers together to simulate the photographs documenting the fiber compression and breaking. I mention this because many of us, including me, to save weight, will sometimes glass only the outside of some parts such as the hulls of vaka and ama. I believe (but don't quote me) that the Gougeons or my narrator, himself a professional multihull designer, were particularly concerned with amas, which take extraordinary stress when to lee on the front of a wave. Evidently, both the obvious stress on the lee-ama, the 'down hill motion on the front of the wave, and the motion of water in a wave's front face have been known to deform that hull-side to destruction during dramatic sailing, and then you regret not glassing the inside too. For a small recreational outrigger hull perhaps this is not something extra to worry about, but I think it surely is for the cross-beams. I am concerned to hear about that spruce destruction! -- Wade

  17. #3517
    Join Date
    Dec 2016
    Location
    EU
    Posts
    388

    Default Re: The outrigger and proa thread

    A iako behaves like an I-beam even if solid. The outer laminations carry the whole load. So one wants a tough bending wood for these layers, ash, hickory, osage orange or black locust. The alternative is unidirectional fiberglass or carbon fiber. You are esentially building a bow or a spring. Spruces are to stiff for this application, and I suspect most cedars also.

  18. #3518
    Join Date
    Apr 2009
    Location
    Merritt Island, Florida
    Posts
    64

    Default

    Quote Originally Posted by Rumars View Post
    A iako behaves like an I-beam even if solid. The outer laminations carry the whole load. So one wants a tough bending wood for these layers, ash, hickory, osage orange or black locust. The alternative is unidirectional fiberglass or carbon fiber. You are esentially building a bow or a spring. Spruces are to stiff for this application, and I suspect most cedars also.


    Thanks! I ended up waiting until I could get a piece of ash. I just clamped up the dry run with 3 layers of Ash, the 2 outer and the center. The other 2 are cedar. Looking forward to get back out on the water!


    Sent from my iPhone using Tapatalk
    Jon
    Building: Ha! I have Toddlers. Just able to get back in the shop and start fixing.
    http://flsail.blogspot.com/
    Built: PK78 dinghy, EasyB canoe, Ulua

  19. #3519
    Join Date
    Aug 2013
    Location
    S.W. Florida
    Posts
    4,473

    Default Re: The outrigger and proa thread

    Greetings, multihullers. I found only one passing reference to Malinowski, and think someone will find this interesting/inspiring/useful.



    This illustrates the rigging, the tilt of the canoe—the raised outrigger—and the carrying capacity of a canoe. This one is well in the water, with a crew of eighteen men.

    A look at the pictures (for instance Plates XXI, XXIV, XXXIX, or XLVII) will give us some idea of the general structure of the native canoes: the body is a long, deep well, connected with an outrigger float, which stretches parallel with the body for almost all its length (see Plates XXI and XXIII), and with a platform going across from one side to the other. The lightness of the material permits it to be much more deeply immersed than any sea-going European craft, and gives it greater buoyancy. It skims the surface, gliding up and down the waves, now hidden by the crests, now riding on top of them. It is a precarious but delightful sensation to sit in the slender body, while the canoe darts on with the float raised, the platform steeply slanting, and water constantly breaking over; or else, still better, to perch on the platform or on the float—the latter only feasible in the bigger canoes—and be carried across on the sea on a sort of suspended raft, gliding over the waves in a manner almost uncanny. Occasionally a wave leaps up and above the platform, and the canoe—unwieldy, square raft as it seems at first—heaves lengthways and crossways, mounting the furrows with graceful agility. When the sail is hoisted, its heavy, stiff folds of golden matting unroll with a characteristic swishing and crackling noise, and the canoe begins to make way; when the water rushes away below with a hiss, and the yellow sail glows against the intense blue of sea and sky—then indeed the romance of sailing seems to open through a new vista.

    (CONT'D AT LINK)
    Argonauts of the Western Pacific, by Bronislaw Malinowski (FREE PROJECT GUTENBERG DOWNLOAD LINK)


    #include [ std-disclaimer ]

    Hope the voyage is a long one.
    May there be many a summer morning when,
    with what pleasure, what joy,
    you come into harbors seen for the first time...

    Ithaka, by Cavafy
    (Keeley - Sherrard translation)

  20. #3520
    Join Date
    Feb 2007
    Location
    Waterbury, Connecticut
    Posts
    2,042

    Default Re: The outrigger and proa thread

    Quote Originally Posted by sharpiefan View Post
    Greetings, multihullers. I found only one passing reference to Malinowski, and think someone will find this interesting/inspiring/useful.
    ...Argonauts of the Western Pacific, by Bronislaw Malinowski (FREE PROJECT GUTENBERG DOWNLOAD LINK)


    #include [ std-disclaimer ]
    --- That is classic reading for anthropology students, and I think should be classic for proa-files. Parts of it read -- as my friend once remarked -- like a "boys' adventure tale" (in the good sense). I love the part where he describes the magical experience of sitting over the flying ama. Enjoy! -- Wade

  21. #3521
    Join Date
    Dec 2011
    Location
    North East England
    Posts
    1,295

    Default Re: The outrigger and proa thread

    Thanks for sharing

  22. #3522
    Join Date
    Oct 2002
    Location
    Coromandel, NZ
    Posts
    270

    Default Re: The outrigger and proa thread

    Quote Originally Posted by wtarzia View Post
    --- That is classic reading for anthropology students, and I think should be classic for proa-files. Parts of it read -- as my friend once remarked -- like a "boys' adventure tale" (in the good sense). I love the part where he describes the magical experience of sitting over the flying ama. Enjoy! -- Wade
    Much of Malinowski's info on the outrigger canoes is also contained in "Canoes of Oceania"
    https://bishopmuseumpress.org/collec...oes-of-oceania

  23. #3523
    Join Date
    Feb 2007
    Location
    Waterbury, Connecticut
    Posts
    2,042

    Default Re: The outrigger and proa thread

    Quote Originally Posted by Gary Dierking View Post
    Much of Malinowski's info on the outrigger canoes is also contained in "Canoes of Oceania"
    https://bishopmuseumpress.org/collec...oes-of-oceania
    --- I was not aware of that.

  24. #3524
    Join Date
    Sep 2015
    Location
    Whangarei New Zealand
    Posts
    592

    Default Re: The outrigger and proa thread

    Diagrams in Canoes of Oceania are good, but pics in Malinowski's book (Argonauts of the Western Pacific) are better than. Canoes of O... clearly showing things like relative size of Ama to waga, as well as sails and other details. '

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •