Lego Minifgures Manufacture
Injection Moulding
How are Lego figures made?
Injection molding is a redistribution manufacturing process used to create plastic parts by injecting molten plastic material into a mold cavity (under high pressure!).
The process starts with a hopper that holds plastic pellets, which are then fed into a heating chamber where they are melted. The melted plastic is then forced into a mold cavity using an archimedes screw, where it cools and solidifies into the desired shape.
Once the part has cooled and hardened, the mold is opened and the finished product is ejected. Injection molding is a widely used process for creating a variety of plastic products.
How are decorative details added?
The decoration on LEGO minifigures is typically added using a process called Pad printing, which is a form of Offset printing. The process involves creating a printing plate with the desired image or pattern, which is then used to transfer the ink onto the surface of the minifigure.
Here are the basic steps of the pad printing process:
The design is created on a computer and converted into a printing plate using specialised software and equipment.
The printing plate is then mounted onto a pad printing machine.
A minifigure is placed onto a holder, which is attached to the machine.
The pad, which is made of silicone rubber, is dipped into the ink and then pressed onto the printing plate, which transfers the ink onto the pad.
The pad is then pressed onto the mini figure, transferring the ink onto the surface.
The ink is cured using heat or ultraviolet light, which sets the ink and makes it permanent.
The pad printing process allows for precise and detailed decoration to be added to the minifigure, including logos, patterns, and designs. The process is also efficient, allowing for multiple colors to be applied quickly and accurately.
It's worth noting that some LEGO mini figures may also have additional decoration added through other processes, such as stickers or moulded parts, but pad printing is the most common method used for adding decoration to mini figures.