everglades challenge sailboat

Discussion in 'Sailboats' started by rapscallion, Mar 6, 2012.

  1. DIY Tri Guy
    Joined: Jan 2012
    Posts: 68
    Likes: 5, Points: 0, Legacy Rep: 90
    Location: FLORIDA, USA

    DIY Tri Guy Junior Member

    Randy Smyth's boat Scissors works because the amas and akas form a parallelogram, and the akas also pivot on the main hull -- a total of 6 pivot points. It's a very slick design, though he had to strengthen the original after losing an ama in the 2011 EC.
    I don't see how the above rig would work unless the amas also pivoted to stay parallel to the main hull.
    - Frank
     
  2. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    here's a few more of Sizzors. that's got to be a complex set of pivots and cables! And I don't see how Gary's will keep the floats in line either, not from the diagram but then again I have actual photos of Sizzors and I don't see how that folds either!

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]

    [​IMG]
     
  3. DIY Tri Guy
    Joined: Jan 2012
    Posts: 68
    Likes: 5, Points: 0, Legacy Rep: 90
    Location: FLORIDA, USA

    DIY Tri Guy Junior Member

    Nice photos, Dennis. I was at the EC launch and it's simpler than you might think. The rig is based in a simple parallelogram, so the amas are always in line with the main hull and each other no matter what the angle of the akas.
    - Frank
     
  4. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    Not my photos, like most, they are just pilfered off the internet. I do however provide whatever visual aids possible when I can. Videos are now a great way to explain things when a still photo won't do. I want to add my lines to the cat for folding and expanding to show how that works. I'm not sure that the same system would work for the proa though. I'm still trying to wrap my head around Sizzors, and might just have to model that to understand it better. At least my fleet of models won't take up the whole backyard!
     
  5. Gary Baigent
    Joined: Jul 2005
    Posts: 3,019
    Likes: 136, Points: 63, Legacy Rep: 509
    Location: auckland nz

    Gary Baigent Senior Member

    Here is my tentative idea of Sid completely folded for trailering, yes, the amas have to pivot; it all becomes reasonably complicated, (that is why Sid is fixed) but still doable; I'm thinking of sliding struts with locking pins. To not capsize while paddling it would be imperative (laughs) to limit the folding to provide some reasonable beam, 9 feet, so wouldn't be completely closed as in trailering drawing.
    Actually, instead of having two rigs mounted on the beam, it would be simpler and less hassle to lower and raise with a conventional una rig setup.
     

    Attached Files:

  6. rob denney
    Joined: Feb 2005
    Posts: 890
    Likes: 285, Points: 63, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    From the biplane aero rig thread, which drifted.


    To win the EC you need something faster, (lighter/longer/better power to weight) than a Tornado. It must also be less than 10' wide. Considerably less if single handed as the bridge transit is quite long and the skipper could only fend off on one side.

    The UFC boat also has to reduce to maximum 24' x 3' so it can be paddled in the St Mary River, and be less than 18' x 3' wide for the 40 mile portage. Ideally it should be big enough to sleep in as well.

    Within the constraints imposed, the aim is simplicity. Everything should be either on or off to eliminate user error when tired.

    Based on the 25' Elementarry http://harryproa.com/Elementarry/SailingPhotos_4.htm a possible boat for both would be a 30' proa with 6' at each end hinged so it flips back and sits on the deck. This makes it 24' for paddling (stern flipped) or 18' for portage, with room between the ends for the 10' windward hull. Total package would be 20" wide (or whatever bunk width you can live with) plus wheels for portaging.

    12' beam would be enough rm for the length, and with external telescoping beams, it could be reduced to 6'8" while afloat, 3' for paddling and 2' for portage. The beams sit in sockets so they could be quickly removed and stowed in the hull. They are very close together (4') to minimise trampoline hassles, which are by far the most time consuming part of rigging/derigging boats like this.

    Unstayed schooner rig with masts hinged above the booms. Unstayed masts flex in a gust so the tired sailor has much more time to react and does not need to reef as often. They also have nothing to undo, fall in the water, kink, fray or forget while raising/lowering. The schooner rig enables steering in shallow water and provides sleeping room in the lee hull between the masts. The hinged masts (we are building 7 of these for 40-45' cats, so it can be done) allow for rapid raising/lowering while afloat and are self stowing as they sit on the booms. The booms are attached to the stub masts which vastly reduces the sheet loads as they are self vanging. Booms and sails stay in place while sailing, paddling and portaging, which speeds things up, reduces error potential and makes for a much tidier package.

    With 25' masts (above the hinge), sail area is 275 sq'. Masts are two part to further reduce the length of the portage package.

    Oversize, lifting, kick up (in both directions) rudders external to the hulls so no daggerboards etc or holes in the hull are required.

    Elementarry weighs 120 kgs/265 lbs with one rig and could be lighter. Add 45 pounds for the second rig. So about 140 kgs/310 lbs, plus payload (anybody got any numbers for this?), crew (one could sail it, maybe 2 for the long paddle) and a bulletproof bottom (infused ply, 10 lbs) on the hulls.

    If you were good enough and just wanted to sail the EC (and out scissor sizzors), then a boat like http://harryproa.com/Texel/texel.htm, might be an option.

    NOTE: I have not done either race (would love to do the EC, too old for the UFC), so may have missed some requirements. Please let me know.

    rob
     
    1 person likes this.
  7. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    Rob, glad you can join in!

    As you can see I've made a proa model along side my cat model so I can play around with them. I even made a scale model of a 30 footer but hadn't done anything with it yet. maybe I'll try to convert it into what you're describing?

    I'd really like to know more about the telescoping of the beam and I'd like to model it.

    UFC update: Sandy Bottom and SOS in the wooden trimaran "Mosquito" has finished the the 1200 event around noon EST today. They did use the boat switch rule because of the low water conditions in the rivers. In one of the youtube videos showing their portage Dawn mentions some pretty tight spots where the Kruger canoe just barely made it thru.

    In second place is Mosquito Magnet and he's just left the Suwannee and entered the gulf headed for Cedar Key, the last check point. From there it's a 125 mile "sprint" to the finish.

    Whale and RiverSlayer are teamed up pulling each other along. It's reported that Whale towed both boats for 11 miles when Riverslayer's feet got bad. Whale said he was repaying a favor for drafting behind Riverslayer for long sections.
     
  8. upchurchmr
    Joined: Feb 2011
    Posts: 3,287
    Likes: 259, Points: 83, Legacy Rep: 579
    Location: Ft. Worth, Tx, USA

    upchurchmr Senior Member

    Rob,

    I checked out your website. Seems to be a little dated. Can you tell about some of the issues that were to be resolved in the single masted boat?

    Marc
     
  9. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    There's a lot I like about the proa and having a longer main hull equals speed!

    I also like the shallow water features, a leeboard or for really shallow water using no boards but using the sails to balance the boat out. This would also work out great in my home waters as well and I can really test this type of boat out nicely here.

    The river sections still has me wondering just how I'm going to propel this craft. I'd really like to use a pedal prop for most of the rivers but I don't know what I'd do when it got tight and skinny. There's an excellent thread on pedal props here on boatdesign.net and there's a guy CoachDave with a big multi person "taxi" that moves along quite nicely and if I could get that performance I'd be just tickled!

    storage: everything will be stashed down in the hulls thru hatches. too many have lost everything and had to DNF because of it, not me!

    shunting: with my proa model I'm getting the feeling for shunting now that I got a physical boat in my hands to help simulate what is suppose to happen.

    Crew: my cat wouldn't be a two person boat, but the proa could be, and just in case I was to find a crew then I'd be wired, but the boat has to solo first.

    sails: I'm thinking a roller furling boom. this way the shape of the sail would stay nice, and I got plenty of reefing and tuning. got no real idea about how I'd do this though. ..... and mast? I'd like to know what rob has got going on! pics?
     
  10. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    The only real example of a roller furling boom that I could find (with in reason) is Mat Layden's Elusion in UFC 2010.

    Since it rolls up nice and even I could have batten and the reef points could be where the battens are rolled onto the boom.

    There would have to be a mast track for the sail so as I lowed the sail the boom could roll it up.
     

    Attached Files:

  11. rob denney
    Joined: Feb 2005
    Posts: 890
    Likes: 285, Points: 63, Legacy Rep: 436
    Location: Australia

    rob denney Senior Member

    Marc
    Very dated, for a bunch of reasons, none of which are very good. Still, development proceeds, just does not get written up so much. What does get written up is on http://au.groups.yahoo.com/group/harryproa/?yguid=312404726[/url]

    Could you tell me where the "single mast issues" were mentioned, please, so I I can tell you what they were and how they have been resolved. The boat has sailed with a single mast, no jib and both or one rudder very successfully for the last few years. Pic attached. The structure just ahead of the front beam is a water driven 4 line retrieval system for a 40 sqm/430 sq' kite I was playing with. The boat currently has a wing mast, and the next step is to make it telescoping.

    Dennis,
    Let me know an email address and i will send you some drawings so you can model the beam telescoping and the ends folding. May take a few days, I have a bit on. Neither is very difficult, the tricky bits are, as always, in the details.

    Roller furling booms are tidy, but extra weight and one more thing to go wrong. Plus, a fast boat needs a vang. These are possible, but difficult to organise on a roller. For a 25' luff and 6' foot they may be more effort than they are worth. The Gougeons Bros have a neat roller arrangement, as do early Farriers.

    I have pedalled a couple of Rick's boats. Awesome is not a big enough word, and the advantages over paddling get bigger as the boat does. However, in shallow or weedy water, you will be paddling, poling or sailing. Any pedal/prop system must have a prop that is easily lifted clear of the water for shallow stuff, removing weed or sailing. Ideally without leaving your seat. On a proa, it should also work in both directions, so you can motor sail. Maybe sit inside the hull pedalling a chain drive connected to a gearbox on the outside of the hull which can be rotated to face either way. Again, no holes below the waterline.

    In my experience, lee boards don't really cut it on fast proas , as they often see loads which are unexpected (eg rotating forwards, swinging to leeward), so have to be highly constrained. Like daggerboards, they don't start working until the boat is moving in a straight line so often stall after a shunt. Oversize rudders can be turned accordingly, making shunting much quicker and more reliable. Plus, two foils in the water is faster, less hassle and less weight than 3.

    Agree about long = fast plus there is more room to stow stuff.

    Shunting is simple once the system is sorted. After the first time, you will wonder what all the fuss was about.

    A schooner will be harder work to sail than a una rig, but still easier than a sloop rigged cat or tri.

    If you want an EC crew, let me know.

    Be interesting to know how often the contestants in each event paddled and why. ie, no wind, head wind, too shallow, overhanging branches, narrow channels, etc. With easily raised masts and a very easily driven boat, you may not pedal enough to justify it.

    Pantographing and horizontal plane folding are cool solutions to beam reduction, if you can work around the trampoline.

    rob
     

    Attached Files:

  12. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    I think I got a way around the tramp! the ship breaker yard is working on a hospital ship, they have these really light weight aluminum litters, I'm gonna go get some today. big zip ties to the outrigger spars and/or lashing should do and be quick and removable . I got pics of them around somewhere .....
     

    Attached Files:

  13. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    here's another of Randy Smyth and Sizzors ......
     

    Attached Files:

  14. upchurchmr
    Joined: Feb 2011
    Posts: 3,287
    Likes: 259, Points: 83, Legacy Rep: 579
    Location: Ft. Worth, Tx, USA

    upchurchmr Senior Member

    So what happened to Sizzors when it broke?
     

  15. spidennis
    Joined: Feb 2007
    Posts: 519
    Likes: 11, Points: 0, Legacy Rep: 124
    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    I don't know. Randy finished stage one via his kayak, just to finish to that point I'd gather. I don't know the fate of Sizzors or how he got the boat back to shore. I heard it was righted with a power boat that actually did the damage, but it's only what I head thru the wt forum.

    In a self shot video he's on Sizzors doing better than wind speed .... when things are going right that boat really moves along but .....
     
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.