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| Posted on 3/6/07 at 07:15 AM | |
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UGH!! I think it is your lamp that is betraying you. You can test the free sample by coating a very small area, then taping a dime to the stencil and putting it in the sun for 3 minutes. The dime will not transmit any UV light and should wash out perfectly. If the stencil breaks down when you washed it out with water, it didn't get enough exposure to cross-link. Low power lamps often lack the "penetration" to completely cross-link the stencil. Elementary exposure judgement is very simple. If the stencil washed out, it didn't get enough exposure. If it doesn't wash out, it was exposed to light or heat and now resists water. If it doesn't wash out where you positive is supposed to stop UV light, the positive is not opaque enough. If you want faster exposure, you will have to invest in faster emulsion like Ulano QTX, or a more powerful lamp than your 100 watt fluorescent bulb. You would do better with a Home Depot 500 watt portable work light with a "J" bulb in it for $14. Remove the safety glass and you will reduce the exposure time. Save your money for a commercial exposure lamp, or suffer long exposure times. QTX is also a pre-sensitized emulsion that is twice as fast as QX-1. If you are still having troubles, call Ed Toney - The Voice of Ulano at 800-221-0616 extension 1302. [Edited on 3/6/07 by richardgreaves] ____________________ Richard Greaves, ASPT Ulano Corp. New York Technical Services 718-943-1338 direct | |
  
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