You already saw part of the process in the article about the Lego Storm Troopers cloning facility, but here’s the whole process:

• First, the raw plastic material gets into the molds to create all the parts: the head, the torso, the miniscule hands, the hips, and the left and right arms and legs, plus any minifig complements, like helmets or tools.

• The head and torsos are always decorated. This is a complicated process that makes the minifig the most expensive part of any Lego set. This is why sets like the Death Star diorama are among the most expensive. The stamping of the colours is usually made in several passes. In older times, the faces always had the same designs. Today, however, they have different features that require different layers (personally, I like the classic ones more than the ones with different faces).

• Once they are decorated, the torsos get into the body assembly machine, where the left and right arms are put into them mechanically. The same machine then places the hands inside the arms with absolute precision at lightning speed.

• The torsos are then taken to the packaging production line, where they are put together in the bags along with the head, hair/helmet/hat, and legs with hips. Before, the machines also connected the heads and legs, so the Lego aficionado would find the minifig complete inside the box. Now, however, this is left for the player except for the vintage minifig set, which comes with the minifigs completely built.

Stay tuned for tomorrow special features on the 30th Anniversary of the Lego minifig. We have some amazing surprises coming, including an exclusive Gizmodo contest that will let you win some of the most famous Lego sets in history. [Go Miniman Go]

The exclusive tour is divided into three parts

While the storage areas are the most impressive part of the factory, I have to admit that nothing had prepared me for the scope and complexity that is required to make and pack 19 billion bricks every year. The scale of this factory, specially compared to the tiny bricks it produces, is absolutely breathtaking.

The warehouse and the mold room

We started in the main warehouse, which is half a kilometre long. Here they house the silos holding the raw plastic granulate. Through them, 60 tons of this material is processed every 24 hours. These towers are connected to the molding machines through a labyrinth of tubes that push the granulate mixtures in a permanent tin-pitched rumble.

It’s the digestive system of the enormous factory, always feeding the molding lines through the tubes and moving big boxes full of pieces–using conveyor belts–into the storage area in an endless and precise dance which never ends: this factory works around the clock to fulfil the worldwide thirst for Lego.

The molding machines

Everything is recycled in the factory. The plastic granulate itself is a by-product from diesel, and whatever is discarded in the manufacturing process gets recycled. The leftover parts from the mold–the plastic that fills the channels that take the hot plastic into the piece negative–fall down the machine, gets ground up, and put back into the production cycle. Any other waste, like faulty pieces or the transparent plastic used to clean the inner tubes when they need to change the production colour of a molding machine, are also ground up and sold to other companies for the production of other things, like pipes and even heating oil.

The machines produce more than two million pieces per hour, churning incessantly into colour- and bar-coded boxes. I looked around and I couldn’t see many people. A woman was in one of those endless aisles looking at a few molding machines with big “QT” signs on them. She was in charge of quality testing, making sure that the production was going perfectly.

At one point I was taking photos of a box of full of yellow bricks, and suddenly the machine stopped working. Fearing I had done something wrong, I saw a big wonky box coming from the distance, some kind of weird transport with strange sensors on the top, straight from a moisture farm on Tatooine or a spice mine in Dune. I stepped back, instantly realising it was one of the many factory robots.

This transport bot was answering the call of the central mainframes, the brains of the Lego body that control every aspect of the process at all times. The mainframes had stopped the production of the machine, following the signal of the sensor next to the box and sending the signal to the robot, alerting it that it had to harvest the crop of bricks. The robots travel down the aisles autonomously, picking up boxes and leaving empty ones so production can be resumed.

The storage cathedrals, decoration and packaging

The robots then put the boxes in the conveyors, which move them into the storage cathedrals (click here to see a complete report on them, the following video only has a brief summary). There, the huge cranebots lift them to the heavens, placing them in endless towers of boxes. There are four of these cathedrals in the Lego factory, and no humans are inside. The mainframes know what it is inside at all times, and order the cranebots to retrieve boxes and send them to decoration and packaging, where Lego sets take their final form.

Here, the Lego pieces may take two ways. One is to go straight to the packaging lines. The other is to go into decoration. Decoration is the most expensive part of the Lego process. Here, the pieces are individually painted with absolute precision, like you can see in detail in this video.

In the packaging lines the pieces are distributed: they are dumped into the machine, which separates them one by one, then counts them using optical sensors, and placed in a generic small box. I watched in amazement, seeing how the pieces fell into these small boxes on a very small conveyor. At every step, one, two, three or whatever amount of pieces will fall into the box, according to the instructions of the set in production.

Along the way, high precision scales measure the weight of the box. The computers know exactly how much a box has to weigh at any stage, indicating that the correct number and kind of pieces are inside. If there’s a variation of a few micro-grams, the alarm jumps and an operator grabs the box, sorts the pieces, and puts the box back into production.

Once the box is complete, the contents are dropped into the plastic wrapping machine, which makes a bag with the pieces inside. The box are then dropped inside another box, and passed into another production line, where more bags would be added until all the set pieces are in place, ready to be packaged and sent to shops all around the world.

As I watched the boxes going away, being wrapped for shipping, I couldn’t help to have this feeling of absolute marvel. From plastic grains to full sets, everything controlled by computers and robots, in a scale that–given the size of most of these pieces–stunned me. Next time you look at that Lego box full of bricks, or your collection of mini-figs, think about how complex and elegant the whole production process is. Your “toy” will have then a completely new dimension.

The Allianz Arena Lego model was built following the original plans from Swiss architects Herzog and de Meuron, using 4,209 hours of work and over a million pieces. It can glow red, blue, and white using interior LEDs, achieving the same lighting effects of the original stadium thanks to a special translucent brick specially manufactured for the project. [Giz's Lego Trip]

Perhaps the sense of humour is a requirement to work there. Or maybe a consequence of the amazingly fun and light atmosphere that I found everywhere around the company. Personally, I think they put some kind of happy-clappy drug in the food—more on that later—because everyone seems to be smiling and having fun while working, even the people checking the bots at the factory.

And for the people who didn’t get the reference at the end of the clip, watch this:

Again please! [Giz's Lego Trip]