We had a nostalgic visit to the National Packard Museum. Nostalgic not because I ever owned a Packard motor car, but because of the old Packard Electric. I did not realize that the company started as Packard Electric making transformers and cable. I only thought of them as making wiring harnesses for cars. For six boring months in 1966 I drew some of those wiring harnesses. But my first week there was spent learning to freehand letter* the GM way. They were still a division of GM in those days. My title was draftsman in those politically incorrect times; drafter became the gender-neutral title later. I doubt that these titles are used today; there are just CAD Operators (CAD=Computer Aided Design).
*Technical lettering is the process of forming letters, numerals, and other characters in technical drawing. It is used to describe, or provide detailed specifications for, an object. With the goals of legibility and uniformity, styles are standardized and lettering ability has little relationship to normal writing ability. Engineering drawings use a Gothic sans-serif script, formed by a series of short strokes. Lower case letters are rare in most drawings of machines.
Freehand lettering is done without the assistance of tools. To regulate lettering height, commonly 3 mm (1⁄8-in), guidelines are drawn. [I drew my guidelines with a sharp blue pencil so it would not show up on the blueprint.]
Wikipedia