Harry Proa Bucket list

Discussion in 'Multihulls' started by Kentaro, Apr 28, 2016.

  1. luckystrike
    Joined: Feb 2010
    Posts: 215
    Likes: 12, Points: 18, Legacy Rep: 92
    Location: Germany

    luckystrike Power Kraut

    Hi Rob,

    still opting for the parachute solution! First have a look around and enyoy your place with the great overview over the seas, then jump off and re-right your boat. :D

    No just kidding!

    In my eves your Bucket List is a masterpiece in simplicity and efficiency. instead trying everything to make things more powerfull and expensive, you rely on lightweight with "normal" materials and clean lines, making everything cheap and fast to build, affordable for nearly everybody. I like that!

    A small sister of Bucket list, with off the shelf- or second hand epuipment could be a real killer in the small (under 30') class in the Silver Rudder Race in Denmark. I wonder what could be done with a used mainsail from a Ventilo 20.

    Michel

    Michel
     
  2. rob denney
    Joined: Feb 2005
    Posts: 635
    Likes: 40, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Short sail on Sunday. Not much breeze, not much speed, but with a deep reefed main (21 sqm/215 sq') and a loose halyard, it got along ok. Nothing broke apart from a tiller extension universal. It shunted fine, steered well with both or either rudder, sailed level, was hardly affected by crew weight position. The bow lifted at quite low speeds, giving hope for planing.

    No winches and only two blocks and tackle (mainsheet and snotter) so the mast lashing, halyard and cunningham were 2:1 with truckies hitches, which was not enough. Got a small single speed winch coming and am playing with alternatives to blocks and tackles (levers and other mechanical advantage devices).

    The to do list is quite long, but mostly small jobs, might be sailing again by Easter.

    Progress blog, pics and videos at http://harryproa.com/?cat=2

    rob
     
  3. jorgepease
    Joined: Feb 2012
    Posts: 1,405
    Likes: 24, Points: 38, Legacy Rep: 75
    Location: Florida

    jorgepease Senior Member

    Man that's a light boat, she should fly!
     
  4. rob denney
    Joined: Feb 2005
    Posts: 635
    Likes: 40, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Certainly should.

    Some of the lightness is attributable to it being a harryproa, some to Intelligent infusion.
     
  5. rob denney
    Joined: Feb 2005
    Posts: 635
    Likes: 40, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Bucket List update.

    After half a dozen sails with a 40% mainsail, it got too cold to play so BL sat on it’s anchor for a couple of months while I decided what to do next. The issues were:

    i) Although there was some interest in chartering racing multis, there was none in either paying for 4 of them or running the business.
    ii) The quality of the build is poor as a result of limited build time during my trips to Adelaide. In particular the leeward hull repair of a screw up with the mould dimensions and one of the beams which has the vacbag and resin absorber stuck inside it.
    iii) A 12m x 8m boat drawing 100mm without (and with) a motor is a handful to maneuver solo in a breeze.
    iv) Anchoring in a busy waterway is fraught. Every time the breeze was up, it was surrounded by kite boarders, most of whom were beginners. A powerboat cut the anchor warp one night, the boat was stopped by a couple of fishermen at 1 am just before it reached the open sea, next stop Chile. A fortnight later, it was impounded by the water police for being anchored in the same spot for over a week. The canal berth I had arranged for bad weather fell through.
    v) I am not going to get time to sail it to regattas.

    At the same time, we started brainstorming a design for the Volvo Ocean Race inshore foiler. This produced 3 new ideas. Foils, an out of hull rig and a triscarph lee hull. Followed by the realisation that an automatically self righting proa was feasible.

    The upshot of all this is that BL is being turned into a trailerable foiler so we can check these ideas out.

    The beams will be reduced to 6m (ease of trailering, shorter load on the trailer, able to fit in my canal berth, chop off the dodgy bit). Righting moment is reduced, but not by much as the rig will be 2m to ww of the leeward hull, supported by stays to the ends of the beams, the same as the Volvo proa. It will not have the diamonds or the extended boom as the current mast does not require them. The rig is easier to raise and lower and allows the easiest means of altering the rake/sail balance. This also is not required with the current rig, but would be if the sail area was maximised.

    The lee hull will be chopped up into 2 x 3.5m hulls, joined by a 6m x 150mm dia carbon tube. The ww hull chopped down to half the height and a cockpit added. The beam clearance is reduced, but once foiling, will be higher than before.

    The rudders and foils will be mounted on the hull sides so they can kick up.

    The end result will be a weight saving of about 40% (500 kgs to 300 kgs), with another 50 to come when the beams and rig are optimized, less than half the windage and no component longer than 6m or heavier than 40 kgs. The loa (12m) stays the same, the sail area on the 3 piece, 16m (1.5m of which is “bury”) telescoping mast drops to about 45sq m.

    Once we know all this works, a range of boats will be available for home or pro builders.

    As always, I expect to be sailing by Xmas. Photos will be on the blog and facebook. The “Volvo Proa” presentation is here http://harryproa.com/wp-content/uploads/2017/…/volvoproa.pdf

    Pictured below is a rendering of a possible Bucket List Mk2, and the foiling Volvo Ocean Race inshore foiler concept.
     

    Attached Files:

    Doug Lord likes this.
  6. UpOnStands
    Joined: Nov 2015
    Posts: 574
    Likes: 5, Points: 18, Legacy Rep: 16
    Location: Sydney

    UpOnStands Senior Member

    So is the Volvo foiler a non-symmetrical catamaran or a proa?
    That is, do the foils reverse for shunting?
     
  7. jorgepease
    Joined: Feb 2012
    Posts: 1,405
    Likes: 24, Points: 38, Legacy Rep: 75
    Location: Florida

    jorgepease Senior Member

    UOS It's a shunting proa, check the presentation link.
     
  8. UpOnStands
    Joined: Nov 2015
    Posts: 574
    Likes: 5, Points: 18, Legacy Rep: 16
    Location: Sydney

    UpOnStands Senior Member

    umm, how do you see the foils, which are said to kickup, being handled during a shunt?
    If they kickup, do they contact the hull?
    New design is very complex. Lots of questions
    By centralizing the mast (not completely of course) does the design approach some sort of tipping point? proa to cat?
     
  9. lucdekeyser
    Joined: Aug 2004
    Posts: 131
    Likes: 2, Points: 18, Legacy Rep: 51
    Location: Belgium

    lucdekeyser Senior Member

    The foils turn 180° with respect to the hulls during the shunt (look at the drawings)
    This design is on the contrary very simple - the complexity stems from being unfamiliar with the behavior of the boat when shunting - for me it helps to focus on the swing of the ww hull with respect to the lw foil pair.
    The transverse position of the mast does not define a continuum from proa to cat, but rather from a pacific to an atlantic proa.
     
  10. Doug Lord
    Joined: May 2009
    Posts: 14,291
    Likes: 124, Points: 73, Legacy Rep: 1362
    Location: Cocoa Beach, Florida

    Doug Lord Flight Ready

    ============================
    Best of luck with the foiler, Rob-looks terrific! Is each foil controlled by a wand?
    If the single foil is always on the lee side then an uptip foil might work well --with no moving parts. Would probably involve a bunch of work to test a section that didn't need to be moved and yet would still provide lift and leeway coupling? The payoff could be pretty cool-just a single fixed foil. Didn't Tom Speer come up with a section that provided lift in either direction? If it worked well then it might be adaptable to an uptip configuration. Anyway, good luck and have fun!
     
  11. rob denney
    Joined: Feb 2005
    Posts: 635
    Likes: 40, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    UOS,
    The Volvo Proa has in hull, non kick up rudders as we did not want to be too radical. We planned to discuss it with them if we were selected. All harryproas, including the test boat have kick up rudders, mounted on the side of the hull.
    The lifting foils are on the bottom of the vertical foils. The latter rotate when shunting (think of a shopping trolley) so the lifting foils are always aligned with the flow.
    The Volvo Proa is as simple as we could make it and fulfill the requirements. The test boat will be simpler.
    Doug,
    2 foils on the lee side, one on the ww side. All of them are T foils which are easier to control, build and operate than uptips, which would require moving parts to work in both directions, regardless of the section.
     
  12. Doug Lord
    Joined: May 2009
    Posts: 14,291
    Likes: 124, Points: 73, Legacy Rep: 1362
    Location: Cocoa Beach, Florida

    Doug Lord Flight Ready

    ==========================
    Rob, I don't get that? Both foil types would have to be able to change their angle of incidence but I can't see why an uptip would have more(any) moving parts?
     
  13. DennisRB
    Joined: Sep 2004
    Posts: 1,264
    Likes: 21, Points: 38, Legacy Rep: 228
    Location: Brisbane

    DennisRB Senior Member

    Getting BL to work was too hard so why not try something 20 times harder?
     
  14. rob denney
    Joined: Feb 2005
    Posts: 635
    Likes: 40, Points: 28, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Doug,
    A bent foil has to be built in a proper mould and carefully bagged. It also has to be very strong and imparts big loads in the hull. I built solid carbon spars for the T foils using scrap timber and G clamps, and a bog mould for the foil which took a couple of hours. If I have got the dimensions/sections wrong or want to play with variations, it will cause no pain to throw them out and build a new set.
    The T foils are mounted on the bottom of the rudders, so no additional boards or hull openings are required.
    T's are wand controlled so require no crew input while sailing. Anything sticking through a daggerboard case is stupid at high speeds. Even stupider in shallow waters where i sail. Controlling foiling by lurching sideways when it gets too high is not optimal.
    All/most non AC boats and boards which foil successfully upwind are T's.
    T foils are easily removed for light air sailing and can be easily swapped for different wind strength/crew weights.

    Dennis,
    Something like that.
    Working on a 12m hull and 8m beams requires a shed and launch equipment which I don't have. 2 x 3.5m hulls and 3 x 6m tubes can be dismantled on the beach, carried across the road and worked on in the garage. Plus, I have limited experience or knowledge of foiling or automatic righting and would rather spend my time and money learning about this than fine tuning something which is basically old news.
     

  15. Doug Lord
    Joined: May 2009
    Posts: 14,291
    Likes: 124, Points: 73, Legacy Rep: 1362
    Location: Cocoa Beach, Florida

    Doug Lord Flight Ready

    Thanks, Rob-good luck!
     
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.