Task To Do:
Design and produce something with a digital fabrication process (incorporating computer-aided design and manufacturing) not covered in another assignment, documenting the requirements that your assignment meets, and including everything necessary to reproduce it. Possibilities include (but are not limited to) composites, textiles, biotechnology, robotics, and cooking.
For this assignment we have chance to stretched our brain and do lot of hands on stuff. On Wednesday, Neil gave us lot of options like fabric/textile, hybrid cooking, biotechnology, composites and robotics. From these options I decided to work on composites.
Composite
What I Have Done:
- Read safety data sheet and technical data sheet.
- Design and fabricate 3D mold.
- Produce a fiber composite part with epoxy resin and coconut coir or husk.
- Gave original files and click heroshot of the project.
What is Composite?
A composite material is made by two or more materials - often ones that have very different properties.
e.g. composite Wood such as plywood, Reinforced concrete and masonry, fiber reinforced polymer,etc.
Composites are an interesting material which combine two components, a fiber and a resin, to give a "composite" material with physical properties that are better than either component alone. This is due to the fiber's strength against tension stress, whereas the resin is stronger against compressive stress. In our case, we used burlap and coco-coir as the fiber, and epoxy as the resin.
Composite material is not the by-product of any chemical reaction between two or more of its constituents. One of its constituents is called the reinforcing phase and the other one, in which the reinforcing phase material is embedded, is called the matrix.
The reinforcing phase material may be in the form of fibers, particles, or flakes (e.g. Glass fibers). The matrix phase materials are generally continuous (e.g. Epoxy resin).
The matrix phase is light but weak. The reinforcing phase is strong and hard and may not be light in weight.
1. Role of the Fiber-
Reinforcements give high strength, stiffness and other improved mechanical properties to the composites.
2. Role of the Epoxy Resin-
To give shape to the composite part, to transfer stresses to the fiber, to keep fibers in a place, etc.
Factors that control the properties of fiber:
A. Length: The fibers can be long or short. Long, continuous fibers are easy to orient and process, but short fibers cannot be controlled fully for proper orientation. Long fibers provide
many benefits over short fibers. These include high strength, impact resistance, low shrinkage, improved surface finish, and dimensional stability.
B. Orientation/ Chip Direction: Fibers oriented in one direction give very high stiffness and strength in that
direction. If the fibers are oriented in more than one direction, such as in a mat, there will be high stiffness and strength in the directions of the fiber orientations. Hence the fibers are usually oriented in directions where high stiffness and strength are required.
My Product
I decided to make planting pot with the help of general purpose epoxy resin and coconut coir.
About Epoxy Resin-
An adhesive, plastic, or other material made from a class of synthetic thermosetting polymers containing epoxide groups. [From Google]
Safety Data Sheet-
Before going for composite, I read safety data sheet of epoxy resin. In which precaution in handling and storage, hazards identification are given. I also read about disposal method or process and cleaning method.
Technical Data Sheet-
General Purpose Epoxies are ideal for complex, multi-piece assemblies. They are water and solvent resistant and available in dual syringes or tubes.
It has high compressive strength. It can be used as a binder, primer and sealer.
About Coconut coir -
It is a natural fiber extracted from the husk of coconut and used in products such as floor mats, doormats, brushes and mattresses. Coir is the fibrous material found between the hard, internal shell and the outer coat of a coconut.[From Google]
Benefits of COCO-COIR pot-
1. Water Holding Capacity: Coco coir has excellent water holding capacity while still promoting good drainage and aeration. Coconut fiber has become a favored grow medium also because it prevents nutrients from leaching away.
2. Coco coir pots allow the roots to grow freely: The texture of the coir pots allows the water and air to penetrate quickly.
3. Transplanting or repotting: Simply dig and transplant the whole coco coir pot into the ground or re-pot it in a big container.
4. Pots provide nutrients to the plants: Coir pots when when transplanted on the ground provide the nutrients of zinc, magnesium, copper and iron to the plants.
5. 100% Bio-degradable: These coir pots purely made from coconut fibers and they break down into smaller chunks in the years yet to come. They are not harmful to nature.
Design-
For designing, I opened the solidworks and select front plane and draw a center line. I draw the shape of pot with dimension as per I wanted.
Afetr this, I used revolved command.
Then I used extrude cut command and my part is ready.
Slice It..!!-
I want to make my 3D object into 2D. For this purpose I have to slice my 3D part. I used Slicer from fusion software.
Step 1: Import the .stl file of the object.
Step 2: Set the dimension of the material which you will use for cutting. For example, I used 600*300 MDF having 3.5mm thickness sheet.I edited the dimension in mm.
Step 3: we can rotate our object.
After slicing I cut it on the epilog laser. Ohh...So many parts and I have to assemble it.
Assembly -
The parts are ready, but it's too confusing. So, their is an option in the slicer from which we can see the path for assembling.
So I assembled the 3D part or mold of pot With the help of video. Also I used the fevistick for connect the parts tightly.
After this I took one transparent plastic paper and cover the mold by it. Pot mold is ready for next work.
Prepare A Fiber Mold:-
Frankly speaking, I don't know the correct way or method for making composite fiber. So, I read the previous year students assignment and trying to find video for coconut fiber on youtube.
Here I am going to use one burlap layer and then coco-coir and epoxy resin.
The ratio of the epoxy resin and hardner is 1:2. I want glossy look for my object so, here I will use more resin.
Material Required-
1.Epoxy Resin
2.Hardener
3.Coco-coir
4.Burlap or jute fiber
5.Hand Gloves
I took plastic covered pot. Then mix epoxy resin and hardener in 1:2 ratio. Stir it and mix well.
Then I start apply the resin on pot. After one layer of resin I took coco fiber and try to stick on resin layer from all the sides.
I again apply epoxy on one layer of coco fiber. But I observed that it not stick properly. After some time the coco fiber fallen down.
I Think the binding is not properly. Two layers i.e first layer of epoxy and second layer of coco fiber are not stick properly.
Two major reason :
1. I compared fiber glass and the natural coco fiber (which I have). The fiberglass is straight and flexible and my coco-fiber are flexible but not straight. I think coco fiber needed processing.
2. The epoxy and hardener ratio is not correct. I used hardener in less quantity.
So, I decided to do it again with 1:3 proportion and also I will use a layer of burlap. Firstly I crush the coconut fiber and make small pieces or particles of it.
I mixed these small particle of coco fiber in epoxy and this is the first layer. Then I took burlap and keep it in epoxy for soaking. After 15 min. the burlap is going for second layer.
Then I mixed whole coco-coir in epoxy and stir it properly. It looks like this.....
Apply this mixture on burlap layer and this time it's good.
Finally It's DONE!!!!!
Vaccum bagging-
Then I moved towards processing or application technique i.e Vaccum bagging. I covered my planting pot in plastic. Then keep it in a vaccum bag. Start the vaccum pump and suck the air.
All work DONE...
I keep it for set this fiber mold. After one day it looks like this....
Final product is looks like this....
