Typewriters, Stencils, and Carbon Copies

More than you ever wanted to know about mid-1900s copying, plus the oldest typewritten letter.

Full-size typewriters, and some compact versions, have a three position ribbon selector: Black, Stencil, and Red. In the stencil setting, the ribbon is not used. Older people (like me), or people who had early jobs using mid-1900s low volume printing and copying technologies such as whiteprint (like me), remember preparing stencils on a typewriter, but this setting is a mystery to many.

Until the 1970s, plain paper copying was rare, and copying onto thermal paper produced poor quality copies. Both types of copiers were expensive and complex machines. Schools, offices, factories, and churches relied on spirit duplicators and mimeograph machines to make copies. These machines are still in use in some areas – they are relatively cheap, simple, use few supplies, and can work without electricity.

A spirit duplicator uses a master made by drawing, writing, or typing on a paper sheet that picks up dye-treated carbon from a thick sheet below it. The master is wrapped around a drum, coated side out, and a solvent is used to dissolve the carbon so it can transfer to sheets of paper rolled under the drum. The usual colour of the carbon is purple, though a few other colours can be added to a master by using different carbon backing sheets. The quality is poor, and the number of copies is limited by the amount of carbon on the master – usually no more than a hundred at best, and the copies get fainter as the carbon depletes. However, a teacher could quickly and easily prepare an assignment for a class or two, and children in school in the 1970s remember receiving handouts still smelling of the solvent.

Though carbon sheets are used to make spirit duplicator masters, these are not the same as the sheets used to make carbon copies (a term which persists in email usage). Carbon copies were typically copies of typewritten correspondence, either for a record of what was sent, or a copy to send to another person, or both.

Carbon copies are made by inserting a thin carbon sheet between paper sheets, or by using a form already prepared with carbon sheets. The typebar would strike the ribbon, and transfer ribbon ink to the top paper. The impact of the typebar, through the ribbon and top sheet, would press against the carbon sheet and the paper below, and transfer carbon to the paper. Most typewriters can accommodate three or four sheets of paper and carbon sheets between them, but the quality drops for every copy.

By the way, carbon paper, sometimes called coal paper, for carbon copies or spirit duplicator masters, is not made with carbon (coal), nor is it paper. It was originally wax on paper, and later plastic (oil) on plastic (film).

A mimeograph machine uses a stencil master, which has holes for the letters (or graphics). The master is wrapped around a cylinder. As the cylinder rotates, ink flows through tiny holes in the cylinder, and then the holes of the stencil master, onto sheets of paper rolled below the drum. The quality can be good. There are various ways to make stencils. A metal foil stencil, cut with a special machine, can be used for thousands of copies, while a paper stencil, cut on a typewriter, can be used for hundreds of copies. As the stencil wears, there is no fading. Instead, small areas of letters, such as the closed space in an a, get filled in. Before computers and cheap copying, any organization that required inexpensive low volume printing, such as for newsletters or flyers, needed only a typewriter and a mimeograph machine to be in business.

The paper stencils made on typewriters aren’t actually cut. The impact of the typebars removes a coating that allows ink to flow through the thin paper. (It’s the weakening of this coating in and around letters during printing that causes stencils to wear). For the best quality “cutting,” the typebars must hit the stencil directly, without the cloth ribbon blunting the type. Thus the stencil setting, which saves ribbon ink and ensures the sharpest and cleanest imprint or “cut” on the stencil.

As a child, I saw a made-for-TV movie where a character with blindness is attending college. They stay up all night to type a long essay, only to discover they used the stencil setting, and the essay must be retyped. That’s the only scene I remember and I can’t tell you when I saw this, let alone the title of the film. It may have stayed with me for its portrayal of a challenge for people with blindness in a task I understood.

Although the film showed a problem with a person using a typewriter, typewriters were invented in part to assist people with blindness. Some early typewriters attempted to produce both printed text and braille text. The oldest existing typewritten letter, from 1808, was written by a person who had lost their sight. View this letter and more correspondence, mostly transcribed letters (in Italian).

It’s disputed whether the builder of the device for the first typewritten letter we have made the first typewriter, but they are credited for inventing carbon paper. The paper was intended as the method for printing the letters on page, instead of the cloth ink ribbons later adopted, but carbon paper still played an important role in the use of typewriters.