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We have detailed instructions on how to do that under: Photopolymer Plate Image Prep (LETTERPRESS).
Regular silkscreen transparencies, drawing on transparency, etc. will not work.
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| Step | Name | Info | Photo (click to enlarge) | ||||
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| 1 | Turn on | Turn on by pulling the big red knob, and then press the power button (circled in blue) |
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| 2 | Figure out settings | Make sure the numbers on the unit correspond to the numbers assigned to you by your professor, TA, or technician. The ones in the photo might not be good for what you are doing. See exposure for suggested times. Do not attempt to change these settings without consulting a professor, TA or technician. You can always use the timer on your phone or the white kitchen timer located in the exposure room if you are using different exposure times than the ones programmed in the machine. The LED numbers on the unit are in seconds. | |||||
| 3 | Preheat & ventilate. | Pre-heat the washout solution & dryer by pressing the corresponding button. Turn on the central ventilation in the exposure room. The switch is near first litho station. | Solution heater ON/OFF button
Dryer ON/OFF button
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| 4 | Pre-exposure | While you are waiting for the unit to heat up, you can pre-expose & expose your plate. PRE EXPOSURE: Lie your plate emulsion side down (the emulsion side has a peel-off clear coating, which you can leave on for now) in the exposure drawer. Put it on top of the translucent cover with the peel off coating facing down. Set a timer on your phone for 20 seconds or set up the kitchen timer in the exposure room. Press the exposure button to start exposing, and after 20sec, press it again to stop exposure. | Exposure button:
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| 5 | Main Exposure | MAIN EXPOSURE Now you can expose your plate. Peel off the transparent covering. Lie your plate emulsion side up in the exposure drawer. Carefully lie your transparencies emulsion side down on the plate. If you are doing a diffusion dither with 2x transparencies, learn to line them up here. The emulsions of the plate and of the transparency should be touching - if you have any text, when you look at it in the drawer, it will be the wrong way. |
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| 6 | Main Exposure & Vacuum | Carefully roll the covering over your plate + transparency. Close the drawer (carefully!) and press the vacuum button. The vacuum is very important to have on, and easy to forget! You can tell the vacuum is working when the Vacuum Gauge needle hovers at a steady place above 0, usually around 0.08. Then press the exposure button to expose for desired amount of time. See exposure for suggested times. You can either use the # of seconds programmed into the machine, and let it turn off automatically; OR, you can use the white timer in the room and time it yourself. Note that if you do it this way, you have to turn off the exposure light yourself by pressing the exposure button again. | How to roll over the cover:
Vaccum on/off button:
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| 7 | Washout | When your plate is done exposing, you will wash it out immediately. It is a good idea to USE GLOVES for this and all the following steps. Make sure the water is at least 1/8" above ALL the bristles in the wash out bath. Use the flashlight on your phone to double check. If not, refill using the "clean h20" bucket in the Light Sensitive cabinet. Open the top cover of the wash out unit on the platemaker. Stick your plate to the black/green rubber on the bottom of the lid. Use the squeegee to clean the rubber backing and your plate off before and after. Stick it on with the emulsion side of your plate facing away from the rubber; in other words, the relief side will be facing toward you. Close the lid, latch it shut, and then press the Washout button. Troubleshooting: If the plate doesn't stay stuck to the backing, it's probably too wet. Squeegee the backing, dry your plate, and try again. You can wash your plate out a second time if there are few parts that are still not completely washed out. | Washout On/Off Button:
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| 8 | Dry | When the washout has finished, you will now dry your plate. Put it emulsion side up in one of the drying drawers. Careful, the drawer handles can be hot. Press the dry time button and wait until it beeps to tell you it is done. Flip it over and dry it again if it hasn't dried completely. | |||||
| 9 | Cure / post-exposure | Put your plate emulsion side up in the exposure drawer. Expose it for the time listed in the exposure section. Turn off the machine. | |||||
| 10 | Finish | Now you can turn off the unit. Leave the washout bath lid open. To clean up:
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