Rather than completely hijack the Denon cassette deck thread I thought I would start a new one. Following on from @Mister X s post about how tape starts out much wider I found this article https://www.rfcafe.com/references/p...tape-is-made-feb-1955-popular-electronics.htm Even back in 1955 when making tape seemed to be more of a cottage industry they were starting out making it 12" wide and then slitting it down to the required width. It wouldn't surprise me if they went even wider as demand increased. A former colleague did an apprenticeship with Kodak and he said that photographic film was made on very wide rolls using machines as high as a house I just found this video showing how NAC are trying to recreate the process other manufacturers used. They are only using 6.5" film though. You would get many video tapes from that. And another film, this time Agfa in 1966 This was the type of Hi-tech operation I was expecting.
I the comments someone pointed out that Agfa had been making photographic film for years, and that many of the processes, like applying liquid to a plastic film then drying it must have been similar.
