Assignments

Composites

Using epoxy

Introduction

Composites are a combination of different components. In our industry, composites are materials made by combining two or more natural or artificial elements. These are made to combine the various physical properties of different materials. These usually consist of fibres and a matrix. When they are combined they create a material which is specialised to do a certain job, for instance to become stronger, lighter or resistant to electricity.



Prerequisites

  • Cloth like materials (Jute sheets, cotton sheets)
  • Newspaper
  • Gloves
  • Epoxy Resin
  • Hardener
  • Weighing Scale
  • Bowl (for mixing)
  • Spatula (for mixing)
  • Wood sheets
  • Cling wrap

The process

  • Wrap two wood sheets completely with cling wrap for using on top and base of the composite mix.
  • Mix epoxy resin and Hardener in the ratio 2:1 in a bowl.
  • 50g of hardener was used for 100g of resin. After pouring the resin and hardener, it is stirred for 2-3 minutes until the mixture becomes warm (exothermic reaction) and more viscous.
  • 50g of hardener was used for 100g of resin. After pouring the resin and hardener, it is stirred for 2-3 minutes until the mixture becomes warm (exothermic reaction) and more viscous.
  • On top of the wood sheet, each layer of jute sheet, white sack piece and newspaper are placed alternatively with the mixture applied on it.
  • 7 layers of materials (jute shheet + white sack piece ) are placed. Newspaper is placed in between the layers to ensure proper spreading of the epoxy mixture.
  • Finally the wood sheet is placed on top the last layer and weight is applied on top for equal transfer.
  • Excess eposxy is poured back to the container by tilting.
  • We used a heavy bench vice to add weight on the composite.
  • This arrangement is kept for 24 - 48 hours to set.
  • The final outcome was laser cut to make a funky looking speech bubble.



Challenges faced

  • Uneven speading of expoxy
  • While using the clear wrap, there were small irregular surfaces that made the surfaces rough
  • After sanding these rough surfaces, the clear epoxy turns translucent because of the surface finish.