|
| Posted on 7/19/05 at 11:29 AM | |
|
|
Hello Micah, There are many things that can contribute to your screens ripping. I find the most common factor is plain all "mis-handling" of the frames. Unfortunately, rather than correct the handling problem, most shops will lower their screen tensions as a quick-fix. And, these decisions are often made by the press operators and screen maker without the knowledge of management. Will it solve the immediate problem? Yes, but it also will have an adverse affect in the long run on your printing depending on how low you go with your tensions. I advise against dropping tensions and instead, maintain them and correct the handling issues. You are correct in pointing out that your washout unit could be one of the culprits. Don't turn the pressure washer on the screen. Turn it on away from the screen and then bring the water to the screen. Do your best to wash out debris from between the mesh and rollers. We have a tendency to concentrate only in the image area of the screen causing all the ink and emulsion to accumulate around the rollers. The emulsion and ink will eventually dry up, turn hard and cause threads to break over time. Avoid using haze remover if you don't have to. If you do, make sure that it is rinsed out promptly and thoroughly as it is a very caustic chemical and will attack or weaken the mesh if left on. Consult your chemical rep for more info. The bottomline is where ever you place your frames, they should be either in mesh-safe mobile racks or carts rather than on the floor leaning against each other. Put something between the frame and any metal like a solvent resistant rubber mat or similar in your washout unit. Follow your screens throughout its entire flow and see how they are handled and where they get placed in each area of the flow. This should give you a good idea of what may be causing your screens to rip over time. Sorry for the long drawn out response. I hope it helps. ____________________ George Maanao Newman Roller Frames Mfg by Stretch Devices, Inc. Regional Manager Western USA, Asia Pacific 858.401.0471 | |
  
|