In mainframe shops with line printers, printouts are produced on continuous “greenbar” paper.

Often, the users of these reports would want these greenbar reports “bursted”, meaning that each page was separated from the next, and the printout stacked. Users usually put these reports into large binders made for this purpose.

Further, some greenbar paper was “multi-part”, meaning there were multiple layers of paper with carbon paper in between. There was two-part, three-part, and five-part paper. The more “parts” there were, the thinner the paper, so that it would all feed through the line printer.

We computer operators would have to operate the machinery to disassemble these printouts so that they were human readable.

The first one is known as a decollator. This is a large (6-10 feet in length) machine that is used to separate all of the layers of paper, as well as remove the carbon paper in between. A decollator took a few minutes just to set up a run, as you had to carefully thread the printout through several series of sprokets, and wind the first few feet of carbon paper around a spool. Then you turned a large wheel to advance the paper very slowly to make sure it was all set. Then you throw the switch, and the whole thing comes alive. There is a large speed control dial, and it’s smart to start it out very slowly.

You didn’t dare turn your back on a decollator, for all kinds of things could go wrong with it. First, the carbon paper winding up on the spool could go hayware and shoot out all over the floor.  Next, the individual copies of printout might not stack neatly (often the case with 5-part).

I believe the decollator we had could decollate three-part, so if you had a five part report you had to run part of it through again, as one of the stacks would still be two-part.

Decollator

Then there is the burster. This is a machine that takes continuous greenbar printout and separates (bursts) the pages and stacks them.  Easier said than done.  Bursters had an uncanny ability to rip individual pages and make a real mess of things. Next to every burster is a large spool of cellophane tape for repairing disasters.

Large computer printouts could consume several BOXES of greenbar, and they could be multi-part. It could take an hour or more to take a multi-box printout, and decollate it all, then burst it. And I tell you that bursting five part paper is no fun – it’s so fragile that the machine would rip a report to shreds if given half a chance.

Burster

I learned some of my best swearing while operating these machines. But, I also learned patience, for it was possible to run an entire large five-part report through these machines without incident. Then again, it’s possible to bowl a perfect game.