A microform document archival method that consists of large quantities of 16mm or 35mm film that has been put together onto big spools. Your average roll of microfilm holds about 3,000 images, which is equal to about six weeks of the New York times.

Libraries commonly keep periodicals on microfilm, and will often have special microfilm viewers that will magnify and project the film onto a screen for you. See microfiche.

Spy Movies, especially those involving James Bond, almost ALWAYS involve smuggling important documents on microfilm.

Microfilm is most popularly identified as a medium for the archival storage (or smuggling) of microscopically printed information.

In this writeup, however, I attempt to describe its use as a covering material for the indoor duration sub-species of freeflight model airplane.

For this purpose, microfilm starts out as a solution of nitrocellulose lacquer, with a small amount of other chemicals mixed in for stabilization.

The solution, at about the consistency of thin syrup, is carefully poured across the surface of standing water in a tank about the size of a bathtub. The water surface must be absolutely motionless. The lacquer quickly spreads across the surface to form a film some hundreds of molecules (.0000056 inches, or thereabouts) thick. The acetone based thinner quickly evaporates, and the film can be lifted from the water on a specially made wooden frame or hoop.

The microfilm, after curing, can be stored for an extended period or used immediately to cover the framework structure of a wing, stabilizer, or propeller. These frameworks, bear in mind, are made from balsa wood strips of about 4-6 pounds per cubic foot density, and on the order of 1 square millimeter in cross section. (I apologize for the egregious mixing of metric with English units). The film is adhered to the framework with saliva applied with an artist's 00 size brush, and trimmed to size with a special heated wire cutting tool. As you might imagine, the whole process is extremely fiddly and difficult, but these measures are necessary to achieve the 1-gram weights that allow these creations to stay aloft for 45 minutes to 1 hour.

Microfilm in this form is thin enough to refract light in a way similar to an oil slick, and experienced builders can judge the thickness (and therefore weight) of the film by the iridescent color. They'll throw out a batch that is too thick and heavy, and pour again.

And, as you might imagine with a nitrocellulose based chemical, the stuff is extremely flammable. Smoking in the vicinity at any point of the process is not advised.