Chapter 8
Placing Artwork on The Screen For Exposure
This should be done in yellow or red light. Remember, emulsions are blind to red and yellow light. You can use any red or yellow colored bulb to work with emulsions. Yellow light bulbs will provide more light to work in however. For a one-color design placing the film positive on the screen for exposure is quite simple. We will place it on the substrate side with the film facing up so that when you look at it from the ink well side the design will "read right". There are many ways to accomplish this task but the simplest way is usually with a ruler and an T square. That is certainly the least expensive way since other methods require expensive jig systems that are calibrated. If the calibration is off, the system does not work.
VIDEO: Can You Use A Yellow Bug Light As Your Safelight?
VIDEO: Safelights For Screen Making
Center the design on the film positive from left to right and set it down about 3 or 4 inches from the top of the frame edge. The top would be the side that is closest to the press operator when mounted in the press. You should allow enough room for ink and squeegee when printing so that ink does not end up on the frame edges. Use clear Scotch tape to hold the film in place on the emulsion coated screen. It is often helpful to make a "dog ear" on the tape for easy removal after being exposed and before washing out. Be sure to keep your design about 2 inches away from the frame edge. Mesh tension is higher near the frame edge and lower toward the center of the screen. Therefore, putting artwork across the screen in such a way that it comes very close to the frame edges will result in different volumes of ink being printed. It will print less ink near the sides and more ink toward the center. The center of the screen is considered the “sweet spot.” While we want to gravitate toward the center of the screen with the film positive, we want to allow enough room for ink and squeegee near the print head clamp, (rear clamp presses), and near the press operator end of the screen. You will also want to allow enough space between designs for easy taping off designs in the event you gang up different designs on one screen.
VIDEO: Getting Your Art To Screen
VIDEO: Placing Your Film On The Screen
VIDEO: Ganging Up Artwork On Film & Screens
VIDEO: Using The "Sweet Spot" On Your Screens
VIDEO: Left Chest Or Crest Print Placement Expanded
For artwork with multiple colors and multiple film positives, you will need to place each film positive so that the registration marks for each film positive fall in the exact same place on each screen. Exact may be a severe term but there should be no more than 1/8 of an inch of variance between the location of each color film positive on the screen. Having your design on the film positive lined up correspondingly with each of the screens will prevent time consuming re-burns and/or work-a-rounds. Rear clamp presses will have more tolerance when it comes to art being of from side to side. However, if the art is rotated even slightly between screens it will make it much more difficult to register if not impossible.
VIDEO: How To Line Up Film Positives On Screens