Single pontoon boat drawing

Discussion in 'Boat Design' started by Saqa, Jun 15, 2021.

  1. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    My aim is to present my idea to the community, inviting tweak or sink participation. The shape and water and air interaction is somehow so vivid in my imagination but to be honest I do not have any technical background to make the call

    Asking the learned ones here on how do you feel something like this will behave?
    Do you have any recommendations to add or subtract anything?

    Location is Hervey Bay, QLD, Australia. Travelling from Torquay Sailing club to Rooneys fishing grounds and return. Fishing will only consist of idling to the GPS marks on arrival, anchoring and deep jigging. Most of the travel will be a straight line out on ok days and if the weather turns foul while out, the return will be along the inside beach of Fraser Island at whatever speed is comfy

    Playing around with concepts that can potentially cross 70km bay in regular ok conditions with good fuel economy, safety, ease of storage and speed. At the m0ment, I am just wondering about all this. They might never actually get built.

    Drawn entirely out of a fantasy 3D mental image. Just a thinking exercise for now as a distraction from the boring fitting out of two current boat projects and part-time study. If a feasible concept does appear, then I might build it once the current projects are done


    This is 1 of 2 concepts. The other is a semi WIG cross tunnel RIB
    Fly a boat exercise https://www.boatdesign.net/threads/fly-a-boat-exercise.65617/

    Originally thinking a cat config, but decided to eliminate all cross-beams and just play with one pontoon only. It's based on a 20' foot long 1m dia aluminium pontoon with sealed ends and two bulkheads creating forward motor bay, cockpit cutout and rear reserve volume. There is an aluminium tail to mount a decent prop and a rudder behind the prop. Pontoon wearing forward and rear inflatable fairing (is this a RIBtoon?) I am preparing drawings to show these details in case words do not paint the picture

    Forward bag attached with pipe end inserted into a 3' socket in the bag and lashed (whipped) with bungee cord. 4 x 6" whips over the 3' span. Rear bag laced on over the spine

    Requirements:
    30 knot cruise will be awesome
    30' Length
    2.4m Max beam
    Air prop with air rudder if superior to implementing an outboard
    2 adults and three fishing outfits, supplies for a few hours trip
    Inflatable dashboard/cockpit in the cutout

    I will load pics and part details to this first post using the edit function as I prepare them with edit date and details of addition. Only edits will be addition of pics and its description

    This is the side view from the first sketch. Showing waterline displacing 1600lb. Next pic to upload will show the fitted pontoon

    [​IMG]Rooster001

    Pic 2 added 15/06/21
    Showing the pontoon with very rough engine, cockpit and prop locations
    [​IMG]Rooster002

    Pic 3 added 15/06/21
    Showing rough locations of outboard style foils
    SE Sport 300 Black Outboard Hydrofoil

    [​IMG]Rooster003

    Pic 4 posted 15/06/21
    Showing an aluminium fabrication forming a V keel and doubling as the exhaust line

    [​IMG]Rooster004

    Pic 5 added 15/06/21

    Top view

    [​IMG]Rooster005

    The side skirts form spray and flow channels as well as fenders. Cockpit is liner is inflatable with protective cushions adding air bag effects. Things like steering wheel and controls recessed into depressions in the liner

    Edit 18/06/21
    Post 61
    Major changes to the lines of the concept

    Concept reconfigured for outwards inclining wing tip foils deployed with rotational action

    Overall length reduced to 26' (opinions welcomed re pros and cons of such a move)

    Beam at the widest point now 3m. Reduced the number of chine lines for ease of drawing and sewing

    New pics. Foils not yet shown. Pics are only of the hulls inflatable fairing, aluminium pontoon insert not shown

    [​IMG]RoosterV2001

    [​IMG]RoosterV2002

    [​IMG]RoosterV2003

    [​IMG]RoosterV2004

    [​IMG]RoosterV2005

    [​IMG]RoosterV2006
     
    Last edited: Jun 17, 2021
  2. Ad Hoc
    Joined: Oct 2008
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    Location: Japan

    Ad Hoc Naval Architect

    This is just a series of lines, not indicating anything about a design at all.

    You can either have comments based upon.. well, frankly, ...just a series of lines which refer to nothing in particular,
    or
    you can post a design that resembles something like this:

    upload_2021-6-15_14-9-24.png

    Where one can comment on the size of the waterjet, the location and size of the engine, the number and location of passengers. The appropriateness or otherwise of the hull form and deadrise angle,...the full load displacement and so on.

    What you have posted, may well be best thing since sliced bread to you... which is fine.... no one can take that away from your imagination.
    But if you are seeking actual real comments and advice, then you need to post a design, that has a real objective, not a series of sketchpad lines.
     

    Attached Files:

    kapnD and bajansailor like this.
  3. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    ..............................
    [/QUOTE]

    C'mon man, is that absolutely necessary to communicate like that? Ad Hoc, please see the text in bold and if you may indulge me, please tell me what that line means to you? Honestly I am feeling a bit lost here whether it is me that is not using the English language properly?
     
  4. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    Pic 2 added 15/06/21
    Showing the pontoon with very rough engine, cockpit and prop locations

    Pic 3 added 15/06/21
    Showing rough locations of outboard style foils
    SE Sport 300 Black Outboard Hydrofoil
     
    Last edited: Jun 15, 2021
  5. Ad Hoc
    Joined: Oct 2008
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    Location: Japan

    Ad Hoc Naval Architect

    You must be reading a different post to that which I have posted. As I have no idea what you're referring to?

    It means what you are doing is unfinished, and likely lacking in thought, which is why it is unfinished. As all you are posting is a work in progress - all on the same post rather than new posts to make it easier to fathom - and just blocks of ideas/thoughts. Ergo, not a finished design, just a collection of constantly changing/adding ideas.

    Without details it is still lacking for anyone to provide suitable commentary.

    For example, a simple question - the engine bay... ok, what size engine, make model, and does it fit in the hull?
    What is currently shown, is lacking in any detail to answer this simple question, thus how can anyone comment on "blocks" to provide the definite answer, as you are seeking?
     
  6. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    Soon come, hold your guns mon

    It takes me a while to output the images, crop, label, upload and link. Will let you know when all the pics are up. That’s what that line means
     
  7. dreamingbarrierreef
    Joined: Oct 2018
    Posts: 49
    Likes: 1, Points: 8
    Location: Colorado

    dreamingbarrierreef dreamingbarreef

    This could still be good & fun exam question for new NA or AE. There's just not enough time for long answers, & short ans be dicey regardless. The 1st img seems to suggest there'd be a low pressure area underneath. If the intent is for more planted ride, it still buckles when buoyancy overcomes the downforce. (So instead of like riding sinewave, maybe more like pulsated.) But adding the foils and all questions gone up in the air again.
     
  8. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    What is the "hogged" bottom all about saqa ? You need some other views
     
  9. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    Off course! More views coming, bwoy hafi cook first ;)

    Guys
    I can see that you all get the point that I am organising the post as I get the chance. Any more curious questions, fire away

    Ad Hoc
    Looks like these two folks get it, but you don't. If you would be kind enough to be a bit patient and let me upload all the pics before releasing your barrage of shortcomings with a work in progress. If you are curious about anything you see so far then fire away ;)
     
    TANSL likes this.
  10. Mr Efficiency
    Joined: Oct 2010
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    Mr Efficiency Senior Member

    Occasionally the idea crosses my mind of a planing boat with a slender central hull, looking a bit like a Bolger Hawkeye, but maintaining the depth in the central "box" keel like a planing cat, just minus one demi-hull, then with ladder foils each side to keep it stable and riding high. One possible problem might be aerated water into the foils.
    Bolger.jpg
     
  11. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    Now this is interesting. I am not familiar with ladder foils though. What I wonder though is wouldn't dynamic balance under way keep it from wobbling over? And a planing pad keep it high?


    Pic 4 posted 15/06/21
    Showing an aluminium fabrication forming a V keel and doubling as the exhaust line
     
    Last edited: Jun 15, 2021
  12. bajansailor
    Joined: Oct 2007
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    Location: Barbados

    bajansailor Marine Surveyor

    Saqa, have you got a plan view drawing of your 'Ribtoon' that you can post please?

    And if you have a midship section drawing as well, then even better.

    Nobody can offer much in the way of overall constructive criticism without these views as well.

    The side profile drawing looks sexy - but what is it's stability like? If it is too narrow it will just fall over, even if it has inflatable sponson training wheels.

    That droopy bow looks sexy - but it might be easy to stuff it into a wave at speed?

    And if it is only secured to the rest of the hull with bungee cords, what are the odds of the bow falling off at speed?

    Thanks for your 'Statement of Requirements' :
    ------------------------------------------
    Location is Hervey Bay, QLD, Australia. Travelling from Torquay Sailing club to Rooneys fishing grounds and return. Fishing will only consist of idling to the GPS marks on arrival, anchoring and deep jigging. Most of the travel will be a straight line out on ok days and if the weather turns foul while out, the return will be along the inside beach of Fraser Island at whatever speed is comfy
    Playing around with concepts that can potentially cross 70km bay in regular ok conditions with good fuel economy, safety, ease of storage and speed.
    -------------------------------------------

    In my opinion the best kind of boat for these conditions and requirements is most probably a wee power cat - similar to the thousands that are out there already, doing the job really well. They have had the advantage of years of evolution, and they have been proven to be safe and comfortable.
    And you can probably buy one in good condition for MUCH less than it will cost to build your proposal.

    Here is a typical example - there are many others also available on the same site.
    Markham 4300 Twin 50 Hp Yamaha 4st: Power Boats | Boats Online for Sale | Fibreglass/grp | Western Australia (WA) - Perth Region CHALLENGE MARINE - Berriman Drive Wangara WA https://www.boatsonline.com.au/boats-for-sale/used/power-boats/markham-4300-twin-50-hp-yamaha-4st/260272

    The asking price is $35,000; do you think you can build your boat for less than this?
     
    Last edited: Jun 15, 2021
  13. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    Hey man, yeah I do have top and front views as well as 3D wireframe any angle. I am able to upload the save file that anyone can open with a compatible program. I have in past imported into freeship

    There is a reason for bands of bungee wraps instead of one long bind. If not done properly, a wrap like that can crush the pipe. Think of it more as a seal with 3 more redundancies. There is mechanical attachments inside to the stringers which I will draw into the top views shortly. If anyone knows a good source for super xfast taper eglass tubes then please let me know. Will save lots of searching. I can get them made very very well if ever required but for this exercise premade ones will be a good start as they might be supplied with tech data. The stringers are based on a pair of them

    I have done many trips in various cats to those grounds. A Noosa cat was the best experience, but a major requirement is ease of storage and another trailer doesn't work for my particular use as I already have to store two, one with a 20'er cat on it, an SUV family car, a Nissan Pathfinder tow car impending. Since the big cat will be moored, I can share that trailer with an easily manageable craft. Another issue is its same old same old....... I am chasing a big wow factor too and not ashamed to admit it :D
     
  14. Mr Efficiency
    Joined: Oct 2010
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    Location: Australia

    Mr Efficiency Senior Member

    What other cats have you been in on the bay, saqa, and how would you rate them ?
     

  15. Saqa
    Joined: Oct 2013
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    Location: Hervey Bay

    Saqa Senior Member

    That is the big question, isn't it, with craft like these?

    I have seen this question raised so many times in so many places with so many craft. An answer seems immediately obvious to me. I can see a full 3d model with environment and flow in my imagination, but I would need to paint a picture with words to explain it, and that doesn't work here. Maybe someone with something like SolidWorks and an ability to generate a mental model from verbal input as well as an interest in bow bouncing can help demonstrate in collaboration?
     
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