When artwork is created, a set of registration marks, or bulleyes, should be included on all the color separations. A "master art positive" or MAP is a composite of all the colors with the registration marks included.
A. Tape your MAP to your screen registration viewing table. It should be placed centered and square in a reverse position so that it reads backwards.
B. Place the frame onto your viewing table over your MAP. By using transparent tape, attach your first color separation to your screen taking care to match the registration marks to each other.
C. The positive should be taped in an upright but reversed position on the mesh so that the design reads backward.
D. Leaving your Map in place repeat this process with every screen required for the job.
E. There are times when you would like to expose more than one job on the same screen. To do this follow the same steps outlined in step C. Just place each MAP you want on the screen onto the viewing area before you start pre-registering the frames. Keep in mind that printing is easier when you allow for 2 or 3 inches of free mesh area around each job.
1. An exposure calculator can be purchased to pin point proper exposure times. Tape it to your coated screen and place it into your exposure unit with the guide facing the light.
2. Start exposing the entire image for two minutes. This is just a suggested random starting place. The emulsion manufacturer will be able to suggest specific times for each product.
3. If you don"t hace an exposure calculatoe place a light blocker on the glass covering only two inches of the step wedge guide and continue your exposure to the light for one minute. Step the blocker over the two inches every minute until you have covered the entire image.
4. After you have finished you will have a screen that has been exposed for two minutes to eight minutes.
5. Remove the step wedge guide and place the frame into your sink with the print side facing you.
6. Wash out your exposure with cool water. Syart by rinsing the print side and then the squeegee side. Let the screen soak for a minute or so and the rinsing on the print side only.
7. Record the time that gives you the best exposure results. Use that time for that emulsion and mesh count combination. Be aware that each mesh count will require a different exposure time.
8. After you wash out the screen you should use block out pens or liquid block out to fill in unwanted holes with a piece of cardboard or paint brush and allow to dry in a clean area.
9. There are many types of tape from masking to permanent. For reclaim use of screens use our low-cost masking tape 500, 505 or 515. When using a frame over and over Blue R-Tape or block-out are the best choices.
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* If the whole design area washes away you have underexposed. You need more time under the light.
* If you cannot wash out the entire image area you have overexposed. You need less time under the light.
* You are looking for the time in between that washes out the cleanest and is the least slimy to the touch on the squeegee side.
