Fanie's Folding Cat

Discussion in 'Multihulls' started by Fanie, Feb 22, 2012.

  1. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    I've been playing with this design for a while, it's not ready yet and everything has not been detailed. The important parts however does work and I made a rough wooden model to show thow the folding will work.

    The cryteria is the cat must be trailable, sailing or motorised, launched by one but preferrable two persons and launching should take only a few minites, of course depends on all the rubbish you wish to take along.

    One of the problems we have when fishing our dams (lakes) is that you have to go in and out every day, wasting time by traveling and fuel. So the idea is to have berting, a small fridge, a head, small galley and of course storage for the groceries and other stuff. So let's say one wants to be able to stay out for at least 5 days, four persons depending on the size boat of course.

    Limitations are the hull width, this goes to 1m200 as two side by side on the trailer will make 2m400, just within trailing legal limits. Length depends on what you want. For a fresh water first time build I was thinkng of around 8m to see how it will work before attempting a 10m later.

    Another limitation is the upper deck sides have to be streight so the hinges can function.

    The deck is two storage boxes side by side connected with a deck long sturdy hinge to stiffen the connections between the two hulls. The deck being boxes will also contibute to stiffness, supported by aluminum beams to support the deck and the hulls as well as acts as guides during folding, will explain as I go along.
     

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  2. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    In the above attachment the folding is done using a gin pole and a winch. Considering your storage in deck can weigh quite a bit, it is going to be quite uncomforatable if you have to unpack everything to make it light enough, so a winch and gin pole does the hard work. They can be removable or permanently fixed

    I didn't mention, as drawed the total beam would be 4m800.

    This drawing indicates what the folded setup would look like. Folded height is 3m roughly, the bridges here are 4m200 if I remember right. The compromise is between the trailerable height, the hull height and the total beam.
     

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  3. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    This is the top view in basic, the deck doesn't have to extend right to the transom.
     

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  4. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    To gain the distance the folded decks would take up I redrawed like this
     

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  5. Fanie
    Joined: Oct 2007
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    Fanie Fanie

    Folded the deck would 'stand' on the hinge.
     

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  6. Fanie
    Joined: Oct 2007
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    Fanie Fanie

    And this is the top view with all the stuff.
     

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  7. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Just to explain a few thing that may look funny. You can have as many cross beams as you like, and there are one short beam.

    When folded on the trailer the long beams ride on the deck while the short beam holds the two hulls upright.

    At the launch you insert the long beams and replace the short beam with a long beam as well. The short beam can now go into storage or perhaps doube as a gin pole.

    Once adrift, the hulls get pushed apart and the weight of the decks will help push the hulls apart, these you lower down using the winch and gin pole.

    Reverse the actions to get the boat back on the trailer, winch the decks up, winch on the trailer, once on the hard remove the long beams and insert the short beam.
     
  8. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Fuel and water tanks in the deck is not a problem, the standard fuel tanks can stand either flat or on their side. The same with plastic water tanks.

    You still have access to inside the hulls while the cat is folded, and you can pack all the groceries inside the deck as well.

    Someone said they saw a chair in deck that folds open when you want to use it, your feet are hence inside the deck and not on top. Any bright ideas there ;) The deck's as drawed are 350mm deep as this will fit most tanks, water tanks, fishing boxes or whatever else.

    Well, lets hear it.
     
  9. Fanie
    Joined: Oct 2007
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    Fanie Fanie

    Ok the long hinges are made by placing two stainless steel round tubes side by side say 500mm apart. You then wrap glass around and along the two lengths of pipes and vac form or hand resin.

    Once cured the stainless gets pulled out of both the sides and you end up with a figure 8 with a very long flat middle. Right in the center of the flat you slit along the length.

    Then turn the two parts so the round holes through the length are side by side and the cut edges are away from each other. Mark and cut say 50 or 100mm parts out each side so that when the length has been cut in a zig zag square pattern, the two hinge lengths would slip into one onother and the holes line up.

    Push one of the stainless tubes through both the two parts and you have a nice tight fitting hinge. I will need to make three of these.
     
  10. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Re making these hulls and other parts is a bit off yet. The workhop is not finished yet and as Manie indicted numerous times our economy is up to sh4t with lots more white taxes on the way. Oh well, you can only do what you can. One day when I'm dead of old age and not done yet some illiterate is likely to stand here scrathing in his nose wondering what the hell all these contraptions was supposed to be...

    Mind you, they probably would only see scrap metal iron they can sell at the scrap yard.
     
  11. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Here is another folding option I considered but you would have a step between the deck and the hulls. Will work if you want more bridgedeck clearance, but watch the trailor hight.
     

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  12. spidennis
    Joined: Feb 2007
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    spidennis Chief Sawdust Sweeper

    There's more than one way to skin a cat huh? It would be nice to see that wooden model at work in a youtube video! The problem with my folding idea is that I lose access to my hatches in the hull when folded, your idea keeps access, cool.
     
  13. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    It's rather streight ferward, most often it's a matter of creating the parts on paper then find the best way to get the most features.

    The masts will be aft, same as I did with the little trimaran, except there can be two masts, one on each hull.

    The mast stand is a slot in the transom so that you can plug the mast foot in place and winch it up without the wind blowing it over. The sail's furling stay then acts as the stay to keep the mast in place.

    The advantage of having two sails is of course you don't have to have extremely long masts to make up a desired sail area, less forces to worry about and of course shorter masts are lighter and easier to handle and transport.

    Since you have two easy to use sails they can be used in various configurations depending on the direction wrt to the wind you're sailing in.
     
  14. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Show what your cat looks like, or where can one see it ?
     

  15. spidennis
    Joined: Feb 2007
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    Location: south padre island, texas

    spidennis Chief Sawdust Sweeper

    Here's one of the videos, there's more on my channel if you look.
    I also have some pics in my gallery here on the forum.
    It beach cat sized, a bit different than what others are doing.
    I'll be able to fit two boats into my garage if I wanted to.
    two would also fit nicely on a trailer ....
     
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