The difference between moulding and casting is a common question.
Moulding and Casting are often confused.
Whilst the two processes are nearly always used in conjunction with each other, they are very different techniques.
Moulding is the process of manufacturing a negative space by pouring or shaping a pliable liquid, such as silicone or plaster, over an object.
Once the moulding material is set, the object is removed, leaving the negative space.
This is where the casting comes in.
Casting is the process of making a duplicate of the original object.
This is done by pouring a liquid material into a mould of that object.
The casting material can be any number of different things, although the most common casting products are resins, plasters, silicones, and stone based products such as cement.
Once a mould is made, any number of castings can be made.
If a large number of castings are required, multiple moulds or even a ‘gang mould’ can be made. This is where multiple pieces are in the same mould.
Sometimes a particular moulding material must be used in order to get a specific casting material out.
The two must be compatible, as some materials will react badly to others.