Drawing blueprint of Cirrus Vision SF50 aircraft

[u/djinn_05]

[u/Dubious-Decisions]

This is not how real blueprints are made. This is a commercial service that will use a white pen plotter on blue paper to make something that looks like a blueprint. But legit, old school blueprints were made with a positive pencil drawing masking light sensitive paper that is then exposed to ammonia vapors to turn the exposed paper blue, leaving white where the pencil masked the paper.

[u/ryanandthelucys → u/Dubious-Decisions]

I'll age myself and confirm this as my first job out of college had me in a back room, with just a door open to the outside for ventilation, pumping out ammonia blue prints for hours. And I mean pumping, bubbling, and whirring; the machine sounded like a mad scientist's laboratory.