Debit and Credit: How Money Is Made

The U.S. Bureau of Engraving and Printing (BEP), which began printing U.S. currency in 1862, is responsible for manufacturing all the paper currency in the United States. Today, the BEP prints currency in Fort Worth, Texas, and Washington, D.C., using cutting-edge technology, skilled craftspeople, special equipment, and so on to print legal tender currency. The process of currency printing involves several distinctive steps, many of which are designed to deter counterfeiters.

Beginning in 2003, the BEP began adding subtle hues to U.S. currency denominations of up to one hundred dollar bills. Although these notes have the same dimensions as previous bills and have a look that is consistent with past currency design, several features have been added to enhance security. The number of fake bills is relatively small, but security features are necessary to thwart modern computer-aided counterfeiting. Portrait watermarks, numeric watermarks, micro printing, and security threads are some of the many features included to deter the illegal printing of U.S. currency.

Supplies for Producing Currency

Printing currency requires distinctive paper and ink, and the BEP keeps careful track of every individual ream that U.S. currency is printed upon. The Crane Paper Company produces the paper used for U.S. currency, which is made up of cotton and linen fibers. Each bill is comprised of seventy-five percent cotton and twenty-five percent linen.

Although every bill uses green ink on the bill, the faces of each bill differ as to the kind of ink used. Black ink is commonly used for all denominations, but ink which changes color is used to print a portion of $10, $20, $50, and $100 bills. Metallic inks are also used on these bills for their freedom icons. The Bureau of Engraving and Printing formulates all of these inks, and they are tested continually for consistent quality.

Designing U.S. Currency

Like most other pieces of art or graphic material, money designing begins general concepts and designs that are refined many times. These sketches are then sent to the Secretary of the Treasury for approval. Currency artists don’t begin from scratch each time but already know which person is going to be portrayed on the bill being designed. The designers, however, are free to choose the portrait that will be used and other elements of the bills.

When creating a new design, designers try to create a note that identifies it easily as U.S. currency and yet contains features designed to make the manufacture of counterfeit bills extremely difficult if not impossible. Digital technology is extensively used in the process in order to create striking designs that convey American strength and dignity.

Offset Printing

Today, many United States currency notes utilize very subtle hues in order to make the bills more secure. In order to achieve this effect, several printing steps are followed. The first of these is offset printing, the initial printing of any of the images on the currency sheets.

Offset printing makes use of offset plates that contain the images of the currency on the plate for printing. Photoengravers image the different color separations onto a negative and then the negative is placed on steel, which will serve as the printing plate. When exposed to light, the image that will eventually be printed on currency paper is burned onto a plate.

Plates are loaded in the Bureau of Engraving and Printing’s presses to print the currency. These presses, which weigh more than 70 tons, are rotary offset presses that print ink onto the currency via the dry offset printing. These presses can print up to 100,000 sheets of currency an hour.

Intaglio Printing

Following offset printing, the currency notes must dry for three days before moving on to intaglio printing. Intaglio printing is the method used to print the portraits, numerals, and other similar elements on each piece of currency. Through this method, ink is positioned directly to the plate, where it remains in engraved grooves until it is transferred onto the currency sheets.

Steel dies engraved with three-dimensional images are used in intaglio printing. Originals are kept so that they can be in the future. Engravers use separate dies for each piece of the note, and some of these engravers will focus on portraits, while others will specialize in numerals and so forth. Many dies from the nineteenth century, for example, could still make notes today.

Once the dies are completed, they are assembled into the back of a currency note. This is then transferred to a master die for the currency via a transfer press. Once these dies are assembled, additional elements like series numbers, quadrant numbers and signatures are engraved onto the plates to make a complete note. Plastic molds are then made before being assembled into one plate to make 32 copies of the original die. This entire process is known as siderography.

Electroplating is the method by which the aforementioned plastic plates have their images transferred to the printing plates. Electricity and chemical solutions are used to literally “grow” the face of a plate in stages. The BEP employees involved in this process must continually check and re-check their work to make sure that no flaw is introduced into the plate itself. The final width of the plate cannot have a deviation in measurement greater than +/- 0.0003 in., a figure that ensures incredible precision.

Once the plates are complete, they are loaded into rotary printing presses. 320,000 notes can be printed every hour on these presses, although the BEP is working to increase productivity to where 500,000 notes can be printed in the same time frame. During the printing process, BEP employees cover the plates’ surface with ink and wipe the excess off, leaving the excess in the crevasses of the plate. When pressed against the currency paper at a tremendous pressure, the bill is impressed with the image and the familiar back of a U.S. note results. This process is called back intaglio printing.

Now the sheets dry for 72 hours before the faces of the currency can be printed. Sheets may stick together, so they are placed in a machine called the jogger to separate the currency sheets.

The next step is Face Intaglio Printing, which follows the same method as back intaglio printing except for the way in which ink is placed on the plates. Ink rollers put different inks on specific portions of the plate so that three different colors will be applied to the front of the currency note.

Mechanical Examination of Currency

After face intaglio printing, the currency sheets must again dry for 72 hours before moving on. After drying, both sides of the currency sheets are examined carefully to eliminate any sheets that have flaws in them from the printing process.

One machine that inspects currency sheets is the Upgraded Offline Currency Inspection System (UOCIS). This is a camera and computer program that examines thousands of bills every hour for the correct placement of the security thread and watermark as well as the trim measurements. For example, a system called Nota-Sav, which examines $1 bills, can detect the smallest inaccuracies. If any flaws are detected under these systems, the sheet is rejected. These rejected sheets will be reconciled to inventory and marked for destruction.

COPE-Pak Printing

Finally, the currency moves into the last step in the printing process — the Currency Overprinting Processing Equipment and Packaging, or COPE-Pak. Under this process, various federal seals are printed on the currency. A separate team of sculpture engravers, siderographers, and plate makers all make these seals and serial numbers for printing on the currency.

Today, two letters, eight numerals, and a one-letter suffix make up a serial number on a bill. The primary letter represents the series of the currency, the next letter indicates where the bill was first issued, and the numbers simply order the sheets being printed.

While passing through COPE, the COPE Vision Inspection System (CVIS) examines each sheet for correctness of the information printed on the bill. The process is so fast that the machine can identify inaccuracies in 200 milliseconds. If sheets are marked as defective, they are then examined by human eyes and removed if they are indeed defective. A sheet that looks exactly the same except that a star is placed after the numbers instead of a letter.

Following this, the bills, which are still attached to one another in large sheets, are collected into stacks of 100 where they are sliced, first horizontally and then vertically to cut the notes from the currency sheets. They are wrapped in groups of 100 with a denomination paper and then gathered into 10 bundles that are held together with a band and wrapped in plastic. Four of these bundles and wrapped once more to form a “brick.” A machine known as a palletizer will then stack 160 “bricks” as two skids of currency.

Packaging Operations

The final stage of currency production is Packaging Operations. Under this process, the skids from the COPE stage are broken into four-brick segments and then shrink-wrapped. A machine then applies a label and the palletizer forms skids of these “bricks” (16,000 individual notes). These skids are then assembled in cash-packs of 40 and stored in the Federal Reserve Vault before they are picked up and distributed by the Federal Reserve Bank.