First, a pattern maker draws a jeans pattern based upon measurements (of samples) that were supplied by the jeans designer or the buyer's merchandiser.
It takes approximately 15 pieces that make up a standard pattern for a pair of standard 5 pocket jeans.
A person, or a computer program, will then calculate the optimal fabric consumption by puzzling all the pieces of the jeans pattern on a paper that is placed on top of the denim fabric. After drawing the cutting
lines onto this paper:
the fabric is ready to be cut, the denim is laid out in layers on a cutting table. Up to 100 layers of denim are stacked and weights are put on top of it to hold the denim
fabric in place, while it is being cut.
The separate parts of the jeans are cut with a textile cutting machine and each piece is then marked with it's size, using a piece of chalk so it won't show after washing.
All of these pieces of cut denim are then put into bundles by size.
It takes about 1.6 meters of denim fabric, several hundred meters of sewing thread, 6 rivets, 1 or 5 jeans buttons, 4 labels (usually imitation leather), and optionally a zipper to make a pair of jeans. An average jeans factory can make about 2.500 pair of jeans per day.
There are different machines for each handling.
On average, it will take about 15 minutes and 12 steps to make one pair of blue jeans.
After the denim jeans are sewn together, they go out to a jeans washing plant where they are washed in what could best be described as: standard, yet very big, washing machines.
A stonewash for 150 pairs of jeans takes 150 kilos of pumice stone and more than 750 liters of water. Depending on how faded the look will have to be, they will be washed somewhere between 30 minutes and 6 hours.
After the stone-washing process the denim garment is inspected for faults and loose threads are cut.
Next the button(s) and rivets are placed using a special type of press.
After that the jeans go on to the garment packing room where final quality inspection takes place and paper tags and labels are placed or attached.
A typical pair of jeans will have a hang tag, joker
ticket, pocket flasher, leg sticker, inside care
label with product of origin and assorted product id tags. When all is
done, the jeans will be placed in a poly bag with proper warning text
and packed in a box or bag, depending on the destination country, as some countries or territories have more strict packing regulations