Goal
The goal of this exercise is to develop a sensitivity to color choices available for printing through a multi color print.
Objective
The objective of this exercise is to create a print exchange with a with a two color print.
Background Reading
- MacDougall, Chapter 6, p 67–83
- MacDougall, Chapter 7, p 85–93
- MacDougall, Chapter 9, p 103–113
- MacDougall, Chapter 10, p 115–123
Safety Notice
- State safety concerns here.
- Do not look directly at the ultraviolet light
- Safety apparel required: gloves, safety glasses, ear plugs, respirator
- Safety Data Sheet (SDS) Index
Exercise
A sensitivity to color and ink types is essential for developing a satisfactory final print. Using the efforts of each student and sharing a portion of the edition, each student will develop a basic ink color book.
Each print will consist of two colors, with a color printed by each student in the assigned pairs.
Station# Monday Group: Colors
- Black/Primrose Yellow
- Opaque Yellow/Process Blue
- Emerald Green/Process Magenta
- Peacock Blue/Process Yellow
- Professional Black/ PMS Cool Grey 10
Station# Wednesday Group: Colors
- Hot Pink Florescent/ Opaque Violet
- Medium Red/Violet
- Jacquard Magenta/Medium Yellow
- Ultra Blue/Orange
- Dark Blue/Fire Red
Part One
Prepare a screen for exposure. Using the provided film positives, expose, washout and dry a screen for each color, or half of the print.
A coated, exposed and dry screen is an essential step to begin printing. With a screen properly locked into the press, taped along the edges and registered to the paper in the press, gather the necessary supplies for printing:
- Ink
- Squeegee
- Water spray bottle
- Paper towels
- Ink scraper
- Newsprint
- Paper
Ensure the following:
- Vacuum is plugged in and switch is in the on position
- Foot switch works
- Materials are close at hand
- Screen blocks are firmly clamped
- Off contact pennies are set
- Counterweight is fastened
Spray a light mist of water on the screen. Wipe evenly to distribute the water.
Emulsion and screen fabric will absorb some water from the ink, causing it to dry too fast. Pre-wetting will minimize this risk.
Give the ink a quick stir to ensure ink it is mixed and consistent. Ink should have the consistency a little thicker than syrup. Add a quick spray of water and stir until correct.
With the screen raised and the squeegee rested at the top (hinge) edge, place a piece of newsprint on the press. Press the foot switch to arrest the paper. Lower the screen and grab the squeegee with both hands. Set the squeegee at a 45 degree angle above the print area and the ink, press firmly down, and draw the squeegee towards the body. Stop once past the image area (print stroke). Make a flood stoke to return the ink and squeegee to the top of the screen. Return the screen to the raised position and press the foot switch to release the paper. Remove paper and inspect. The ink should be a little wet and runny. Place prints on drying rack. Repeat the process with newsprint until the print has crisp edges only where needed.
Once ready, place a sheet of final paper in the press. This time, pay careful attention to the placement using the registration guides to ensure correct alignment. Repeat print sequence until complete.
Warning: Do not allow ink to dry in the screen. Doing so will cause permanent damage to the screen.
Once printing is complete, scrape all remaining ink back to receptacle. Spray screen with a light mist of water and unlock from press.
Transport screen, squeegee and cards to washout boot. Gently clean the ink from the screen and tools. Remove the tape and scrub with the brush to remove any adhesive residue. Check screen for clarity in backlight before cleanup. Turn off light and water once done.
Warning: Do not allow emulsion remover to dry in the screen. Doing so will cause permanent damage to the screen.
Part Two
Aligning the second and subsequent colors to the first is essential to maintaining print proficiency. Place the film positive and/or paper securely aligned to the registration guides and activate the press vacuum. Place the screen close to registration as possible and tighten the lockdowns on the hinges. Try to adjust the registration through wing nuts on rear of press. The registration guides on each color should match. Press down the screen and make sure the emulsion and screen colors do not interfere with the process. Carefully align screen to positive or first color. If the screen does not align, reset the registration screws in the rear and the place new guides on the press. Once registration is confirmed, proceed to printing the second (subsequent) colors.
Often the color registration can change over time. Slight adjustments to the system can be made, but it is likely the variation in printing is to blame. It is better to look for trend over more than one print than just assume inconsistencies.
If colors misregister, please consider the cause as a troubleshooting exercise:
Paper: humidity can cause the paper to swell and shrink several points. Rack paper (place on drying rack) 24 hours before printing to acclimate.
Poor first color printing: sloppy paper placement, poor stopblock placement, loose hinges or registration guides.
Poor second color: Poor technique, squeegee angle, poor paper placement.
Part Three
Once printing and cleanup is completed, label each print by printer, print number, print date, color name and ink manufacturer in the spaces provided on the print.
Part Four
Exchange the prints with the others in class by taking the corresponding numbered print from each stack.
Technical Specifications
- 5 x 7 in. (landscape) artwork area centered on an 9 x 12 in. sheet of paper.
- Two colors total, one color per person
- Digital templates are available for download.
Assessment
- The following rubric posted on D2L will determine assignment score: Exercise Grading
Techniques
Brainstorming, conceptual development, drawing, digital image development, emulsion coating, exposure, washout, registration, printing, cleanup, reclamation.
Supplies
Artwork, computer, appropriate software, film positives, screen, emulsion, exposure unit, washout booth, printing press, squeegee, paper, emulsion remover, scrub brush.
Deadlines
Monday/Wednesday, February 27/March 1, 2017. Exercise Given.
Monday/Wednesday, February 27/March 1, 2017. Observed by instructor as part of group demonstration.