Open Source Sea Chair
by Studio Swine


This movie by designers Studio Swine demonstrates how waste plastic picked up by fishing trawlers can be transformed into chairs on board the boats.

Open Source Sea Chair by Studio Swine

Studio Swine first presented the idea in collaboration with Kieren Jones at the Royal College of Art show in 2011 and have since simplified the process to build the chairs using a small factory onboard vessels. They have released a manual so others can build the chairs too.

Plastic caught in fishing nets or found washed up on the shore is sorted according to colour and chopped into small bits, then melted at 130 degrees centigrade in a DIY furnace.

Open Source Sea Chair by Studio Swine

Some is then squashed between two flat slabs of heavy metal or stone to create the seat, while more is scraped into a mould formed from bent scraps of aluminium.

Cooled and solidified by the sea water, the seat and three legs are then scraped with a knife to tidy the edges and screwed together to create the Sea Chair.

Open Source Sea Chair by Studio Swine

Studio Swine have also designed a mobile food stall for cooking and selling pig heads and glasses made from human hair.

Scroll on for instructions for creating a Sea Chair from the studio:

Open Source Sea Chair by Studio Swine

Studio Swine has created an open source design based on 'Sea Chair' by Studio Swine & Kieren Jones, accompanied by a film of the process where a chair is made on a fishing boat at sea.

The United Nations estimates some 100 million tons of plastic waste to be contaminating in the worlds oceans, a proportion of which washes up on coastlines across the globe, last year Japan had over 200 thousand tons of plastic debris wash up along it's shores. This abundance of plastic presents an opportunity where the material is delivered by the sea to coasts where it can be processed to make new products with the intention of removing the plastic from the marine environment for good. The open source design uses readily available materials and basic DIY skills to enable the the creation of a sea chair.

You can download the Sea Chair manual here.

Open Source Sea Chair by Studio Swine

Things you need:

Furnace: a camping stove, a food tin, a steel kitchen pan with lid, a cooking thermometer, thick tin foil, glass fibre roofing insulation, crushed charcoal (for best results use perforated charcoal from an old water filter)

Moulds: a scrap aluminium L section (6cm x 6cm x 40cm approx.), two steel sheets (for best results polished stone off cuts from kitchen worktops, sink cut-outs or leftover floor tiles), Wax for mould release (beeswax or car polish)

Tools: a metal scraper, hacksaw, drill + metal bits, screw driver, three long screws, one or two small bolts & nuts

For Collecting: two buckets, kitchen or fine garden sieve, dustpan and brush, big bag, rubber gloves

The steps:

1. Collecting

Collecting plastic on the beach is the easiest way to get sea plastic; it prevents the washed up plastic returning to the sea to harm marine life.

Look at beaches during low tides where materials have been deposited, these are generally sandy beaches with debris along the strand line.

A dustpan and brush is effective for collecting small plastic pellets known as nurdles. These are often found deposited in lines below the main strand line of heavier materials such as seaweed. If the sand is flat and damp, then they can be swept off the surface without collecting the sand. Where sand is collected, they can easily be separated by sinking in a bucket of water and scooping out the floating plastic with a sieve.

Try to sort the plastic at this stage using the plastic chart, separate PET from LDPE, HDPE & PP which share similar melting points. Dispose of any PVC or Polystyrene collected. Small plastic pieces and nurdles are not possible to identify easily but if your averages are correct with the large items, the mix will work.

The plastic should all be broken up into pieces around 1cm x 1cm, this can be done by hand or a kitchen food processor. Add some water to the mix when using the processor to avoid the plastic from melting around the blades.

Remember: Dry the plastic before melting.

Open Source Sea Chair by Studio Swine

2. Melting

Some essential precautions should be taken when melting plastic. Some plastics emit toxic fumes when melted. The lid and filter will help minimalise exposure to these, but also do any melting in a very well ventilated place away from others, outside if possible. Use a good mask and goggles to protect your eyes from smoke. Hot plastic will stick to the skin, so always wear thick gloves and long sleeves, leather gardening gloves are fine.

In the manual, there is a chart to identify plastics. However, chances are you won’t be able to easily identify a lot of the plastics you’ve collected. The key is to collect a sizeable amount of plastics of the same type so that they will mix well together when melted. It’s common to find large amounts of the same type of nurdles on a particular beach near where a spill once occurred, after you’ve identified the melting point they can form the majority of the mix that glues the rest together. Other beaches may contain mostly PET due to large amounts of discarded drinks bottles whilst some beaches contain a mix.

The majority of plastic waste is made of type1, 2, and 4 plastics. Wherever possible, avoid polystyrene and PVC, as they emit toxic fumes. The plastic pellets, or "nurdles", are all thermoplastics, which means they can me re-melted. Small plastic fragments found in the top layer of the ocean are most often HDPE, LDPE, and PP, as they are less dense than sea water and float, but, even if the plastic you find are thermosetting (which do not melt) they will still form an aggregate within the melted mass.

Once you have sorted your plastic and prepared it for use you can add them to the furnace.

Check the pan when the temperature reaches around 180ºC. If the mix is still hard, turn the heat up to 250ºC, checking at intervals to see when the mix is molten. As soon as the mix is molten enough to form a doughy ball in the pan when stirred, it is ready to use. Don’t worry if some of the plastic pieces aren’t fully melted, as long as the majority are, they will form a colourful aggregate within the material. Be careful not to leave the mixture too long, or the plastic will begin to burn and create more toxic smoke.

You need to decide whether your plastic mix is mostly Type 2, 4 & 5 or Type 1. In most cases it’s best to make a mix that mostly consists of Type 2, 4 & 5 which melt in the range of 110 - 170°C and use the Type 2 (melts at 250°C) as a aggregate.

If melting mainly Type 1 (PET) the plastics with a lower melting temperature can be added when the mix is molten and the stove turned off just before filling the moulds.

To make a stool, it’s recommended you heat around 3 batches of plastic separately, filling the pan each time about 1/3 full. Adding too much in one go will make it difficult to achieve an even temperature through the mix. An improvised windshield may be required for your furnace to reach higher temperatures.

Open Source Sea Chair by Studio Swine

3. Casting

Polish the leg mould with a cloth, and preheat the mould over the gas stove.

Use a metal scraper to scoop the plastic into the leg mould, overfilling them slightly. Press the full leg mould upside down against the flat surface used for seat mould. Press down on the mould until the metal sides are flat against the surface and the excess plastic squeezes out from either end. The excess should be cut off with the metal scraper and added back into the pot to be reused. Submerge the mould in cold water, this speeds up the curing process and makes the plastic contract away from the mould making it easy to remove.

When three legs are complete, a large blob can be melted to form the seat. Polished granite or marble kitchen worktop off cuts are the most effective surface for casting against, a sheet of smooth metal can be used as well, but it should be lubricated with oil or wax to avoid sticking to the plastic. Preheat the surface of the mould so the plastic stays in a molten state for pouring which will result in a smoother finish.

4. Assembling

Mark out an equilateral triangle on the base of the stool where the legs are positioned. Drill holes and screw in legs with screws approximately 3 inches long. If required, use some of the leftover melted plastic to weld the legs to the base of the seat to add strength and prevent them twisting.

  • Nick

    FINALLY some sustainable design that is fully contemporary and not some weird kind of Greenpeace merchandise made of cardboard.

    It assesses the problem without the usual snobbish, radical, post-hippie way of looking at the problem of overproduction and pollution but creating instead a powerful product and a beautiful video.

    All the best to you, Studio Swine!

  • Chris

    One screw per leg, seriously?

  • why

    Sorry, but I don’t agree with you, Nick!

    It is definitely an interesting concept to take the plastic rubbish that swims in the oceans as a resource for material. But then creating a stool from it, with tools that are a hundred years old. Neither the process of making the stool nor the stool itself is interesting. I even doubt that it is a good functioning stool when you look at the way it is assembled. Taking rubbish and creating rubbish again?! What is the point? Why not create something that is really relevant and of high quality?

    Making a nice video by playing with the depth of focus is just not enough!

    • Nick

      I agree with you on your more technical observations, but I think they are not really relevant to a project like this which, in my opinion, has not been conceived nor developed nor produced to be used in my house or yours.

      If we look at it as Studio Swine’s way to send a message on the numerous ways we are polluting our planet I think it’s quite well done and relevant. Sustainability in design has very often been discussed and addressed either in a very naive way (cardboard, recycled materials etc) or in a radical way (stop producing with polymers). I think that both these approaches are very ineffective, the first because it deals lightly, and in some cases stupidly, with a very complex problem of our times, and the second because it’s quite utopian to think to renovate the actual production methods without proposing equally economically favourable options to the industry.

      This project is obviously not functional or perfect, in fact it’s a self produced prototype and not industrially produced for mass consumption which delivers an important message in a direct way.

      • Josh V

        I have to agree with why on this one. Yes, the message is important, but no one will go through all this effort to make a worthless stool. As why said, they’re turning rubbish into rubbish. This is no better than the naive methods you’re talking about. I think the message is lost when it’s delivered through unrealistic means. I’d rather spend the extra money on a stool that will last me several decades than this thing that would be lucky to last a year.

        A real solution might be to create a device that can melt ocean plastic into usable material for something like a 3D printer and have some company set up to harvest the ocean plastic, refine it into something universally usable, and make it cheap and easy to purchase and use. You have to make the means and methods easier than buying a stool at Ikea or Walmart, otherwise no one will care and nothing will change. Maybe that’s pessimistic, but it’s certainly realistic.

        • Clement

          I think this is not furniture but more like functional art. The fact that they label each chair with its location makes it unique.

          Yes, the picture here is ugly but when you see the actual piece you will notice all the texture and the color. That, and the story behind the stool, will make you think more of what the rubbish was, why it is there and so on. You won’t think that much if you buy a fine stool from Ikea right? Or will you?

    • tom

      Nick, I do agree with you, this project is cool. I am at home for a week where there are beaches and lots of plastic. Firstly all the plastic removed from the beach will be a positive move in itself, secondly, this one applies to Nick, you can relax a bit and take from the project what you want. I’m not going to be building a stool but using the technique to create something which I do need in my house. People are so boring that they look at projects like this and start ranting and pointing out every single flaw. “I would rather buy a really high quality stool that will last ages” – since when do people sit on stools? It’s a concept… jeez.

  • mik

    Lovely idea: a designer-fisherman. I love it. Beautiful and inspiring video.

  • Ryan Smith

    Honestly, people talk sh*t. I have worked for the second largest kitchen retailer in the UK for several years in a process involving over 20 kitchen furniture manufacturers.

    To suggest all of this non-polymer nonsense is just stupid for an industry that relies on PVC pressing, ABS edging and melamine pressing. Many industries would collapse without having good quality polymers that are easy to work with. Also suggesting methods of recycling things from the oceans (most vast space on Earth) – instead of focusing on production line structuring, engineering and reducing carbon emissions (which is a little bit more important).

    Companies must make money to survive and keep economies running, instead of bothering about impractical, unimportant projects like this. It is an artistic pile of sh*t that people use to preach about recycling – once you students work in a factory (where things are made) and not in an office (where things are designed) you will realise this.

  • Laura

    I understand what they are trying to do. I would say this is more art than design. The issue with this for me is that they are creating more harmful gases by melting everything down!

  • donna Buckbee

    Let’s send factory ships out to the plastic swirls, harvest the plastic, form wafers to serve as polar bear platforms or, at least, artificial polar ice caps. We clean up the mess and deflect sunlight from the warming Arctic Ocean.

  • Concerned Citizen

    It would make sense if the plastic were turned into something they could use on board. That stool will not withstand the rigours aboard a fishing trawler.

  • A great way to recycle. This is a good idea to at least reduce the amount of waste at sea. It could be very useful onboard the ship too.

  • Roger

    For those of you who are focused on function, streamlining production lines and aesthetic quality you might like to read this: