Group assignment4: Moulding and Casting
This group assignment aims to compare different materials used on the molding and casting procedure. The materials that we used in casting are; epoxy resin, and gypsum. Thus, material used in molding are machinable wax, and silicon.
Materials used in moulding
Silicone
It calls as the rubber mold making. The material is not classified as hazardous on the EC regulation, but it contains some hazardous components that's why you need to know the safety data sheet of the material. "ACC Silicones ACD" is the silicon name we are using, it's a 2 part addition cure silicone moulding rubber.
Features of the silicone
- Low viscosity
- Fast cure
- 1:1 mix ratio
- High tear resistance
More of material characteristics are shown in the following technical data sheet
And the following safety data sheets show the safety guidelines for silicon. The silicon is not hazardous, and chemically stable, It's liquid at room temperature, it has a little bit of smell but not produce any excessive smell. It is a it sticky that's why we use gloves in order to prevent any minor injuries.
Machinable Wax
A block of purple machinable wax was used in the milling process. It is solid at room temperature. It is non hazardous, non toxic, and it does not pose any risks to the environment. However, at elevated temperatures, it must be handled with heat-resistant gloves. It can catch fire when heated above flash point (240 degrees Celsius). It is chemically stable, but must be kept afar from strong oxidizing agents, to avoid the production of carbon dioxide and carbon monoxide. More information is given in the link below.
Materials used in casting
Epoxy Resin
Resin material can include both solid and highly viscous materials, but commonly refers to liquids which harden based on heat, setting agents, or light. Typically, modified or synthetic resins are used for manufacturing – they can be produced from natural components with additives or consist of artificial polymers. Resins also naturally give off fumes, and unless you work in a well-ventilated area, molecules from the fumes will get into your lungs and cause irritation there, too. Harmful when exposed to eyes or ingested: Never let resin near or into your eyes or mouth unless they're specifically marked as non-toxic.
Gypsum
Gypsum plaster, white cementing material made by partial or complete dehydration of the mineral gypsum, commonly with special retarders or hardeners added. Applied in a plastic state (with water), it sets and hardens by chemical recombination of the gypsum with water.