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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

As an example, let's establish press time at $150/hr and 450 prints per hour. This means our press time per sheet is 33 cents ($150/450 prints). If our changeover takes 15 minutes to make holder adjustments, we will only be able to print 338 images compared to being ready to run without an adjustment in the first hour. This adds 11 cents to our cost per sheet during the first hour ($150/338.) You can do the math on whatever run size you have. But be aware that as press-run lengths get smaller and smaller, adding any changeover time to the process can have a significant impact on your over-all costs. In fact, it may make the difference between a profitable job and one that costs you money.

Frame inventory

Frame inventory is one of my pet hot-button issues. Money tied up in anything that doesn't directly produce value is waste. Proponents of lean manufacturing know this all too well. It's their mantra. With this in mind, finding the balance for your frame inventory is one of the keys to keeping the production flow moving smoothly.

Obviously, if you do not have a frame with the correct mesh count when you need it, you will delay production, or you will have to get creative at the expense of additional press adjustments and associated work-arounds that add cost and reduce efficiency. Using percent open area is very helpful in reducing the number of mesh counts with which you work. That is step one. Step two is to begin charting and tracking your daily usage by mesh count and frame size. If you are fortunate enough to use a single frame size, the process is relatively painless. When you have multiple frame sizes, you must determine whether the image really needs to go on the frame chosen or whether perceived convenience was your motivation. Do this over a two-month period. Keep track of which sizes and meshes you use by the day of the week and by daily volume. You may find that some very interesting patterns emerge.


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