Thread: Ruth Card
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Old 11-09-2011, 05:45 PM
steve B steve B is offline
Steve Birmingham
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Location: eastern Mass.
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Wet sheet transfers can happen at a few points during the production. Some of those can have the ink lined up exactly, but not all of them. I'll explain those after I get a couple of the other questions out of the way.

The offset transfers being lined up has nothing to do with the registration or the cutting. The registration is a function of the platemaking and the press adjustment. The cutting is a completely different operation. (Although offset transfers can happen during cutting)

Wether the offset is over or under the green back printing doesn't matter. All that would indicate is wether the back was printed before the front or after. Printing it after the front makes sense as it's only one color -less work would be ruined if there was a problem.

On most "modern" presses the sheets are fed from a stack of sheets and run through the press in excatly the same position. The press then deposits them on a removable platform. During this phase, there's a bit of air between the sheets. This air makes the sheets move easily in relation to the stack. But when it's time to do the next step, you need a very neat stack of sheets. so the press has a set of guides to direct the sheets to be exactly on top of each other.

Now if that stack is allowed to get too tall, the air will be forced out, and the weight of the stack will make offset transfers. The very bottom of the stack will be the clearest, and the offsets will get weaker farther up the stack.
Offsets that happen there will all be aligned exactly with the fronts.
A good press operator switches the removable platforms before this happens.

The rest of the places offsets can happen are during handling. And in that handling the sheets aren't usually aligned as precisely because a number of sheets are being moved from one place to another.

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Since the offset on the Ruth is a complete offset either Goudeys were printed on a multi color press(Like 2-4 or more presses attached together each doing one color) OR they were printed in a big hurry. Since the print shop was probably trying to do them as cheaply as possible they likely were rushing and overstacking.


Steve B
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