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And you think you have problems...

(September 2003) posted on Fri Oct 17, 2003

Visit a printing facility where standard operating procedures, equipment maintenance and cleaning, and production procedures are failing.

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By Carol Swift, Peter Kiddell

The ink mixing (using the term loosely) was carried out in an enclosed room where machine parts also were cleaned. Pad-printing plates and printing screens also were produced in this room. The cleaning tank was an open plastic bowl regularly filled with cleaning solvent. The combination of cleaning solvent, ink solvent, and screen wash produced a heady mixture. One operator commented, "Sometime ago, Mary passed out while she was mixing inks, but she recovered after having a cup of coffee. They installed an exhaust system, but it's too noisy, so we only switch it on if we feel dizzy."

The exposure unit was used to expose both stencils and photopolymer plates for pad printing. The unit was filthy, and there was no record of when the exposure lamp had last been replaced. On average, each screen or plate had to be remade three or four times before it was suitable for use. And when a screen or plate could finally be put on the machine, it often would break down within a few prints. Alterations were made to the exposure time until the image was okay and the screen/plate appeared hard enough. Some of the operators dried the pad plates in an oven after developing, while others didn't think it was even necessary.

The film positives used for stencil and plate exposure were a disgrace. They were covered with scraps of dirt and scratches. The films were made for producing pad-printing plates and appeared right-reading when the emulsion side was on the back. These films were also used for producing screens, but nobody in the company knew that the emulsion had to be on the other side for stencil exposure. They never could understand why the fine detail on their stencils was often degraded. Hence, the impression they had was that screen printing only was suitable for printing large areas. A few years ago, when they changed from white to orange mesh, the problems improved slightly but the fine detail was still poor.

"What do your standard operating procedures say?" we asked. "Oh, we don't bother with those. They were written by the quality department," one employee replied. When we reminded them that they operate under ISO 9000 standards, they responded with "What's that?!"


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