Re: What no-one has mentioned yet... - DRUMS
Fastrand drums were actually made by a sewer pipe manufacturer. They were the only people who could make a drum of the size true enough to spin up to the high speeds needed.
The cabinet for them included mount points for a hydraulic crane that would be required if you ever needed to remove the drum.
The Fastrand standards were still echoing through OS2200 15 years ago in the various options available.
I think my favorite drum device was the ICL one that used 255mag cards in a hopper and a drum transport. The cards would drop and secure to the drum, then you could read and write to them, and they would eject back to the hopper.
Of course, as time went on the mechanism would loosen up and the cards wear and then would come the day two or three cards wold drop at once. The operators said it sounded like when you were a kid and used clothes pegs and cigarette cards (ask yer grandad) to make your bike sound like a motorbike. Often wished I'd seen that one up close, but I came in ten years too late.
I've seen manuals for exchangeable drums that were conical - you screwed them into the drive small end first, pushed the go button and they would be lowered until the heads would fly. Never seen it in the wild though. I think they were ICL equipment, but can't be certain. Working from memory here.