Thursday, July 31, 2008

Windmill vs. Cylinder

As I was running a job on our KS cylinder this week I was again reminded of the differences between a platen job press and a cylinder. The latter aren't called "buchdruck" (book printing) presses in Germany for nothing – they are truly better suited for long runs of one big job than a bunch of smaller ones. Things such as roller installation and adjustment, oiling, etc. take significantly longer with the cylinder. The minimum amount of ink required for the fountain is three to four times that of the windmill.

More than these, the key difference to me is momentum. The cylinder is a juggernaut; you can't stop and start it instantly like the windmill. The windmill is perfect for short runs because you can stop it dead with a sheet in the grippers, tweak the register, and run just one more sheet for another proof. You can run a few hundred sheets while wasting only a couple of sheets. The cylinder needs to get up to speed, and then you must run at least two sheets as the first will have excess ink from multiple roller passes. Then you can either print two more sheets using the stop lever at the delivery, or you can get by without printing any more sheets by using the quick stop lever. This will run two sheets through without printing, which must be returned to the feeder.

That said, for the right kind of job the cylinder is unstoppable. Nothing can lay down a heavy solid as well, and of course they came in L, XL and XXL compared to platens. Ours is the "baby" cylinder (KS for Kleine Schnellpress) with a 15"x20.5" sheet size. If you have the room and can find one that hasn't been butchered into a diecutter, Heidelberg made them up to a sheet size of 25"x35". The register is easily tweaked without tools, and some other adjustments are very easy and precise as well. The cylinder will also handle most any printing, diecutting or scoring job you throw at it. For the vast majority of jobs you get the feeling the machine isn't even breaking a sweat, where you can tell with a platen press that it's starting to work hard past a certain point.

To me what makes the windmill endearing (as much as a machine can be) is that it's human-scaled. When you stand in front of it, it's all right there and there's a lever for each of your hands. It's tall and narrow and you can get all the way around it quickly. Despite its strength it almost feels delicate. The cylinder press is a car-sized brute. It's quite intimidating and you always are aware that there's a lot of metal moving around that could thoroughly ruin your day. The windmill has that too of course, but friendlier somehow.

So, as long as you know what you're getting into, each machine is genius in its own right. Also, as you have just read, the mind has lots of time to wander on those long jobs...

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