Channel 4 documentry, mid 80's ... can you name it ?

I vaguely remember a documentry that was shown on (almost positive) Channel 4 in the early to mid 80's one sunday afternoon. It was shot in the 1940's or 1950's and was about a company called Jahco Engineering (or possibly Jaco, Jacko, Jago or some similar spelling ... pronounced Jacko). This was a heavy engineering company in the US, with some very progressive manufacturing practices, almost Japanese like ... very unusual for American industry of the time.

One scene I remember was a guy arriving late for his shift. As soon as he walks onto the floor of the machine shop, and it's massive, with hundreds of lathes and milling machines, all the workers who spot him start banging on steel plate with hammers. He makes a bee line through the shop floor, with this noise following him, and dives onto his machine, mortified with embarrassment, with all his mates shouting at him for letting them down by holding up the line.

I've searched the web for any reference to the programme or company, but can't find anything relevant. Does anybody remember anything else, or the name of the programme or company ??