Ditto Machine Spirit Duplicator of Yesteryear

The Spirit duplicator.  The copy print machines of yesteryear.  Cannot remember?  Maybe this will jar the cobwebs.  Paper Tiger.

Ditto machines were commonly used in schools, and the students believed that sniffing the solvent fumes from a freshly copied sheet would provide a high—a reasonable assumption given the instances and effectiveness of substance sniffing. My teacher says that the kids would spend the five minutes after receiving a new sheet just smelling it.

Built in 1923, it is perhaps best known by one of the manufacturers.  Ditto, Inc., although other companies such as A.B. Sick, Banda, and Standard made them also.   Like mimeograph machines, it also used a rotary drum to help make the copies.  But it did not use ink.  It was used to produce low to mid volume copies, such as in schools, churches, and offices.  The methyl alcohol in the duplicating fluid provided the characteristic aroma.

VisWiki.  The process. 

The duplicator used two-ply “spirit masters”. The first sheet could be typed, drawn, or written upon. The second sheet was coated with a layer of wax that had been impregnated with one of a variety of colorants. The pressure of writing or typing on the top sheet transferred colored wax to its back side, producing a mirror image of the desired marks. (This acted like a reverse of carbon paper.) The two sheets were then separated, and the first sheet was fastened onto the drum of the (manual or electrical) machine, with the waxed side out.

There is no ink used in spirit duplication. As the paper moves through the printer, the solvent is spread across each sheet by an absorbent wick. When the solvent-impregnated paper comes into contact with the waxed original, it dissolves just enough of the pigmented wax to print the image onto the sheet as it goes under the printing drum.

“Spirit duplicator.”
Image courtesy of http://viswiki.com/en/Spirit_duplicator.

Remember the color purple?

Colors – The usual wax color was aniline purple, a cheap, durable pigment that provided good contrast, but masters were also manufactured in red, green, blue, black, and the hard-to-find orange, yellow, and brown. All except black reproduced in pastel shades: pink, mint, sky blue, etc. Ditto had the useful ability to print multiple colors in a single pass, which made it popular with cartoonists. Multi-colored designs could be made by swapping out the waxed second sheets; for instance, shading in only the red portion of an illustration while the top sheet was positioned over a red-waxed second sheet. This was possible because the pungent-smelling duplicating fluid (typically a 50/50 mix of isopropanol and methanol) was not ink, but a clear solvent.

Paper – This process worked best with cheap, lightweight paper stocks, but when the sheets of paper were impregnated with the solvent they could easily crease or crumple, jamming the machine. One well-made master could at most print about 500 copies before the pigment was exhausted and the print quality became illegibly faint. If fewer copies were required, the master could be removed from the printing drum and saved for future use.

Smell – The aroma of pages fresh off the duplicator combined with the cool touch from the evaporating alcohol was a memorable feature of school life for those who attended in the spirit duplicator era. A pop culture reference to this is to be found in the film Fast Times At Ridgemont High. At one point a teacher hands out a duplicated exam paper and every student in the class immediately lifts it to his or her nose and inhales.

Dead Media.  The term ditto for copy comes to mind. 

The term Ditto evokes the memory to the saying “Ditto” meaning copy. Furthermore, there is the Ditto marks, which are still used today.

They were not cheap.

The cost of the machine was relatively high in price. “Their main drawback was a substantially higher initial cost” (Rhodes 145). The Ditto Liquid Duplicator went for $200 for a hand- cranked model and $265 for an electric machine (in today’s prices $2,256 to $2989) (Rhodes 145).

Nice to have relatively inexpensive home office copiers and printers nowadays. 


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