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Determining and Maintaining Optimum Screen-Inventory Levels

(November 2006) posted on Mon Dec 18, 2006

Learn how to use mesh and frame management to streamline changeovers and ensure that screens are always ready when needed.


By Mark A. Coudray

If you use a pre-alignment system, chances are very good you'll use a standard frame size. The object, whether you use a pin-registration system or a three-point lay system, is to load, lock, and go. Having multiple frame sizes can change this approach by adding frame-holder adjustment to the process. And while we are on the topic of holder adjustment, it's worth noting that any time you adjust a holder, you run the risk of not tightening down evenly or missing a lockdown altogether. This is especially true for carousel presses, some of which may hold as many as 18 screens. Of course, if you miss a lockdown, the chances of something moving during the run are much greater. Hence, in the interest of consistency, a predictable outcome, and repeatable future performance, the fewer things we change, the better off we are.

Consumption of mesh, emulsion, adhesive, and tape are short-term issues. The increased cost in these areas is far overshadowed by the much faster setups and increased earning potential of additional available press hours. Another component to consider is whether the press changeover will increase the running speed, thus lowering the cost per print.

Here are some guidelines for those who must use multiple frame sizes. At the outset, establish clear rules as to what size frames will be used for each situation. Once this is established, work through the variables surrounding changeover with different sizes. Systematically arrange and streamline the process to maintain as many common factors as possible.

Changes you make take time to settle. I always test changes by asking whether I'm adding value or adding cost to the final product. Value is defined as anything the customer would be willing to pay for if it were itemized on the invoice. Press changeovers certainly do not qualify unless we can significantly increase our prints per hour by making the change.


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