Building a floating island/raft from PET plastic bottles like Richart Sowa did.

Discussion in 'Boat Design' started by Boucaneer, Sep 26, 2014.

  1. WestVanHan
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    WestVanHan Not a Senior Member

    Personally I'd ditch all this plastic stuff and go ferro-have seen barges 100 years old in Europe and doing fine.

    Sitting around in my area for 65 years plus,some of them for 80 years.
    Some of them are 90-110 years old-yearly maintenance is to pump out the rain water

    http://www.thesunshinecoast.com/about/gianthulks.html

    Put a couple layers of swimming pool/pond membrane over areas you want to garden in...they're usually warrantied for 20 years so ought to last much longer.
     
  2. Boucaneer
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    Boucaneer Junior Member

    Thank you all, great ideas flowing here.

    May I ask a question please Manie B,

    Do your club jetties have cleats or mooring posts fitted to the ferocement and polystyrene?

    If so how thick is the ferocement please?

    Thank you.
     
  3. AndySGray
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    AndySGray Senior Member

    There have been a few interesting things tried with concrete - the dome of the pantheon built around 20 centuries ago, used pumice stone as aggregate - the pumace is so light it can float.

    More recently they have a process for foamed concrete which uses special additives and detergents and air is blown into the concrete as its poured to give a very lightweight structure - I doubt this is within your means unless it is a very large island.

    Someone already mentioned a polystyrene core and cement outer - what about making a lightweight (Bouyant) concrete by replacing the aggregate with shredded polystyrene (foam) and packing peanuts - I'm sure your local dump would supply as much as needed for free.

    There is even a modern rebar alternative made from Basalt which will never rust, which would be ideal
     
  4. rwatson
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    rwatson Senior Member

    Manies sugestion is right on the money, but permanent constructions may be subject to government regulations.

    If you are in the wild area, where there are no restrictions for permanent moorings, you may get away with it, but most countries wont allow you to build a little island empire wherever you like.

    You may have to construction something that can be towed to pretend that it is a boat.
     
  5. Boucaneer
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    Boucaneer Junior Member

    Yes, I agree.

    Because I am thinking in sections of 8' wide hexagon that can be picked up by a couple of guys and rowed into place on the lake, I will register the hexagon rafts as under 12' unpowered craft/vessels.

    One central hexagon with another six hexagons circling that, all rowed or motored into place and attached/moored to the central vessel. Then 12 hexagons circling the 7 island base, and then maybe 18 surrounding that.

    If I have to move I can move the sections individually or in two or three sections.

    I was looking at PVC piping for the floatation but it certainly does add up in cost, it's not cheap that PVC pipe. So another thought is to use bottles in a lengths sausage shape gaffer tapped together and fibreglass and polyester resin around them making a floating tube that is inexpensive to make.

    All topped of with plywood decking with drainage holes throughout and then using coconut fibre to grow the greenery instead of earth to keep the weight down.

    A different design to the more industrial and professional floating islands but I think it could work.

    Any thought on this design would be gratefully appreciated.

    Thanks and cheers.
     
  6. Manie B
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    Manie B Senior Member

    I will try and get photos next time I get there as I'm not sure how the blocks are interlinked.
    I like the hexagon idea, but that is complicated, simple square blocks can interlink easily, you could even have old car tyres in between the blocks as fenders, lock the blocks together with galvanised chain and any steel brackets must be hot dipped galvanised.
    With 4 nice blocks and a wooden platform you can already build your first "cabin" on top and move in.
     
  7. Rurudyne
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    Rurudyne Senior Member

    If you are dealing with length constraints because of tax laws, since they'll probably want to measure from vertex to opposite vertex, you may want to consider geometrically lopping off the tips of your hexagons so that you can maximize the surface area of any section. I'm also thinking it possible that if you build a structure over several they will then say it's larger than 12' if avoiding these is important, so the larger the hut you can put on just one section the better. Of course then your home becomes a series of interconnected huts and I've no idea how you would feel about that.

    For some reason this set up is making me think of Myst....
     
  8. Boucaneer
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    Boucaneer Junior Member

    Yes, I like the hexagon design as it can make a circle island rather than a square or rectangle, looking more natural and set into the scenery more.

    It need not have to stay in a circle shape either, it can be bolted together with flat bar or galvanised fittings if configured in a triangle, a straight line or curve depending on the surrounding moorings and area.

    I like the fact it is a modular system that can be added to and moved individualy through small locks and river canals also.

    To build something that can be lifted by three or four guys and launched would help logistic too as dependance on crains, lifts or expensive ramps would be unnecessary too.

    I have to find out if my bottle/polyester resin tubes would be waterproof for longevity now, I hope so.
     
  9. Boucaneer
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    Boucaneer Junior Member

    Thank you Rurudyne,

    Yes, it's a one simple woven bamboo traditional circle structure/hut on one section of hexagon that we are planning. We may have one bamboo structure each on several hexagons.

    As each hexagon has individual floatation, balance over the entire modular island wouldn't be a problem.

    It is in the tropics so nice and cool with mosquito nets lining the woven bamboo walls and another mosquito net over the bed. We will have another structure as a cooking/eating and social hut. Maybe even BBQ on the beach. I wouldn't mind walking from one hut to another one.

    It's not just the tax laws, it's the collision regulations on nav lighting a boat over a certain length. With small unpowered boats we can just use a single white light on the hexagon bases.

    We may keep the tip of the vertex's as I wouldn't like any gaps someone may break there leg down there.

    Still great ideas coming in chaps. Thank you.

    P.S Who or what is Myst please Rurudyne?
     
  10. Rurudyne
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    Rurudyne Senior Member

    Myst is a series of first person puzzle solving games, the most recent in 2005, that featured exotic man-made or enhanced environments.
     
  11. rwatson
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    rwatson Senior Member

    Like these little cabins ....



    Myself, i would not do Octagons, from a building complexity, and performance point of view.

    Building complex shapes is a pain, and octagons are not very 'slippery' against waves and wind.

    Imagine very strong winds and tides, and how much drag they would have.

    Maybe you could consider the 'arrowhead' configuration. Several modules joined together could easily swing from a large anchor, and be much more easily towed as a group or individually.
     

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  12. Boucaneer
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    Boucaneer Junior Member

    Yes, I think our little huts we will make will be circular. It seems easier and i do like a round house.

    You know I was drinking a cup of tea playing with a set of penny's I have on the bar to represent the hexagon patterns and shape configurations. It amazes me, so many different possible shapes. I added another two hexagon bases and came up with that arrowhead configuration. I liked it, i guess great minds think alike, although it didn't come to my mind to use it for towing. The penny didn't drop, so thank you. :)

    I am undecided about whether to use swinging moorings or trot mooring, I guess I may use trot moorings if there is vessel traffic, some of the lakes are tidal, so not to cause an unmanned collision. Is there any bonuses to using a swinging mooring please?

    I am really want to get these built now. I just have to look into using polyester resin to firm a tube around plastic bottles formed into a log shape. I hope it will work.

    I think I will use parallel tubing for the floatation/hull and remember which direction to tow/row or motor the bases. I was looking at 15" diameter piping or completly cover the underside of the deck with 10" diameter piping to give a ton of floatation buoyancy on a 48 square foot hexagon deck base

    I don't really like the octagon shape as it has a square gapped shape in tesalation, I do prefer the tesalated hexagon though.

    Does anyone know of a cheaper pipe I can use instead of PVC that will still have a good longevity?

    I want to thank you guys for your comments and support, it really does help put more energy into this project for me. To discuss something helps so much, and even better when talking to boat minded people. Much better than a pub.

    Thank you.
     
  13. portacruise
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    portacruise Senior Member

    How long do you want this thing to last, and what is your budget? Are the plastic bottles about cost or recycling as they probably won't all provide predictable floatation for very long due to eventual stress leaks?

    Maybe cheapest pipe can be found at industrial metal recycling or scrap yard places. Look around for used culvert pipe, used telephone poles, large diameter PVC, etc.

    Hope this helps.

    PC




     
  14. rwatson
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    rwatson Senior Member

    Time and time again, the material solution recommended for this project has been placed in front of you.

    Re-inforced concrete.

    For longevity, toughness, economy - you cant go past it.

    It is a material easier to use, and cheaper than any other. You may not find it comfortable mentally, so why not make a small module in you back yard, say 4 or 5 metres long, and get a 'feel' for it. It should end up being light enough for 2 people to move it around, and if nothing else, it can become a vegetable garden.
     

  15. Boucaneer
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    Boucaneer Junior Member

    Thank you portacruise,

    Yes, the plastic bottles are about cost, I would prefer to use PVC pipe. I don't really have a budget, I worked out that 10" diameter would cost £280 to just cover the 48 squared feet base of a hexagon. When we have to make 19 it certainly adds up.

    I didn't want to use PET bottles as the air can leak from the bottles over time and they can degrade into there chemical ingredients over time.

    I was thinking and planning on researching if it was in a polyester resin casing that would help deter the chemical breakdown of the plastic bottles.

    I am certain I would prefer to use PVC piping or a cheaper but long lasting pipe instead.
    As we are building this in India I am not sure of the recycling availability of used and recycled PVC piping available. It would be great if there was, but I am unsure.

    I wanted to research another plan b if we were unable to find used or cheap PVC. I was hoping the fibreglass resin encapsulated PET bottles might of been a solution.

    It certainly isn't my first choice though, I would prefer not to. So more research and hopefully I will find the fibreglass resin may help.
     
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