What is Rotational Moulding?
Rotational moulding, roto-moulding or rota-moulding is the process of hollow plastic moulding, multiple materials can be used but the most commonly used material is polyethylene. This is a relatively cost-effective process for a large range of plastic products, small to large from lawn mower wheels to boat containers.
How's it Made?
A hollow tool manufactured from sheet steel, cast aluminium or CNC machined aluminium depending on the product design and complexity is charged with a specific volume of plastic powder, each individual tool has its own powder weight depending on the size of the product and wall thickness, wall thickness can be determined by upping or lowering the volume of powder used.
Once charged the tool will enter an oven at a predetermined temperature and will begin rotating on a vertical & horizontal plate, this process adheres the inner lining of the tool with molten plastic and begins to form said product from the outside in, creating a hollow cast.
After a set time the tool will leave the oven and enter its cooling station, continuing to spin on a vertical & horizontal plate the molten plastic inside the tool will begin to cool this process shrinks the product pulling it away from the tool wall and is now ready to be emptied.