Within the study of plastic, the students will cook different bioplastics with different recipes and proportions of ingredients to study the mechanical properties of the material. With a laser cutter, once they got the right material, they could design and make an object to see if it works.
The aim of this activity is to raise awareness about the use of materials in a Fab Lab and its composition by creating our own compostable bioplastic sheet following the instructions step by step. The students will be aware of the time and care that a biomaterial creation process requires.
Instruments (every 2-3 people)
A pan
A wooden spoon
A meter
A weighting scale
A teaspoon
A knife
A mixer
A 1m x 0.5m non-porous board
Ingredients (for a board)
100 gr of cornflour
50 ml of white vinegar
50 ml of vegetable glycerin
100 gr of organic waste (orange peel, lemon, watermelon, beetroot, onion, coffee grounds, etc.)
1200ml of water
Cooking bioplastics with your own organic waste. (90')
Introduction (30′)
In this session, we will present some examples of bioplastic made with different recipes. The students will touch the examples to feel their textures, thicknesses, different grades of elasticity, etc.
After that, we will laser cut a piece of bioplastic to see how this material works with that technology and to do some examples of cutting and engraving to define the parameters we could start to use.
Cutting parameters
Power: 30
Speed: 40
Engraving parameters
Power: 12-15
Speed: 200
Cooking our compostable bioplastic (60′)
As every student has been asked to bring a minimum of 100 gr of organic waste to this session, we will cook a recipe using it.
Instruments (every 2-3 people)
A pan
A wooden spoon
A meter
A weighting scale
A teaspoon
A knife
A mixer
A 1m x 0.5m non-porous board
Ingredients (for a board)
100 gr of cornflour
50 ml of white vinegar
50 ml of vegetable glycerin
100 gr of organic waste (orange peel, lemon, watermelon, beetroot, onion, coffee grounds, etc.)
1200ml of water
Know how:
1-Chop the organic residue and beat it with a bit of water.
2-Pour the rest of the water into the pot and mix in the cornflour. Continue to stir, add the vinegar, and then the glycerin.
3-Keep removing until it thickens. Before it boils, add the mixture to the mixer with the residue.
4-Mix it until the mixture is homogeneous.
5-Pour the mixture on top of the board and keep tilting it until there is a layer of about 2mm.
6- Store the board flat for 4-6 days in a dry place, away from direct sunlight, air currents, and sudden changes in temperature.
See the results, do it again, and design your object. (90')
Introduction (15′)
In this session, we will see the results of our last week’s work on the boards. We won’t peel off our bioplastic if it is not completely dry. Otherwise, we will use a cutter to separate the perimeter of the bioplastic from the board. After that, we will carefully separate the sheet with our hands.
Do it again and/or design (60′)
Once every student has their bioplastic sheet, if the sheet is in good condition, the student could start to design the pattern of the object that wants to fabricate. Otherwise, they will have to repeat the process.
Share the process (15′)
During the last minutes of the session, every student will share the process publicly.
Fabricate your object (90')
In this session, we will laser-cut the different object patterns, we could use the heat sealer, the sewing machine, or other tools available in the Fab Lab to fabricate the prototypes of our object. Once the object or prototypes of the object are finished, we will document the process to the final exhibit.