Why can't I burn my screens correctly?
A number of factors may determine why screens aren’t burning correctly. Let's look at the most common issues.
I can't get the emulsion to stick. Did you degrease your screen? Degreaser will remove oils and other contaminants that hinder emulsion from adhering to the screen. Did you use an exposure calculator to help dial in your exposure times? If so, what does it read? A properly burned screen will wash out to the seventh mark on the exposure calculator. Underexposed screens will bubble and release from the mesh during rinse out. You’d be able to wash past the seventh mark on the calculator. Overexposed screens will not completely wash out finer detail. You’ll also know it’s overexposed if you can’t wash out to the seventh mark. What side of the screen did you try to spray out the image from? Only spray out from the t-shirt side. Spraying out from the squeegee side may cause the emulsion to release from the mesh
I can't spray the image out of the emulsion. What are you using to print your films?Using RIP software? If your film positive is not dense enough, it will not stop the light and therefore, the image will not properly expose. If your film does not have built in UV-blocking ingredients, then it will not stop the light. Again, the image will not properly expose to the screen. What kind of exposure unit do you have? Is it a compression lid exposure unit? If you do not have enough positive contact between the film, the glass, and the emulsion, light can creep around the edges and make the image very difficult or impossible to spray out. Is the area where you store your screens 100% light safe? Light leakage will pre-expose the surface of the emulsion, making it close to impossible to spray out an image. Did you bring the screen out into direct light at any point? Direct light will pre-expose the emulsion, making it close to impossible to spray out an image. Are you using the 21 step grayscale calculator? If so, what step did it rinse out to? If the exposure strip did not spray out at all, you probably have light leakage where you are storing your screens. If you could spray it out — was it easy or difficult? If it was easy, then your films are probably not dark enough. If it was difficult, then you probably have light leakage. How long ago did you coat the screen you are exposing? Coated screens have a shelf life of up to six weeks. We usually advise to not keep a screen coated for more than four weeks to make sure they are always in optimal condition. Are you using high water pressure to spray out the image? Low water pressure takes far longer to rinse out an image compared to higher pressure devices.