CORCORAN PRINTMAKIN'

Alternative Etching and inking part II

Alternative etching process

How to levigate a stone.

How to draw  and etch a stone! 

How to ETCH a stone

1. Begin with a clean stone.
2. Place boarder gum on the edges of the stone approximately 1inch wide. Allow for gum to dry.
3. Take either- Lithography crayons of 1, 3, 5 softness and draw on the stone, use tousche and make a wash, or use a reductive process to draw on the stone. *(see other post)
4. Time to etch- Take three to four small cups and fill them up with straight gum and then take the Nitric Acid and pour in drops according to the hardness or soft ness of the crayon.   ** #1 Crayon - 6-7 drops of Nitric acid.   #3 Crayon  5-4 drops of Nitric Acid   #5 Crayon  2-0 drops of Nitric Acid   Alcohol Wash- 0-3 drops of Nitric Acid  Water Wash- 2-4  Lithotine Wash- 4-8 drops of Nitric Acid **
5. Take Rosin and Talc powders and rub into the stone. 
6. Cover the the stone in acid in the areas with corrisponding crayons and acids. Cover the lightest part with the lightest acids to avoid the drawing from disappearing. Cover the darkest part with the strongest acids to have those to stay.  Cover the white parts with also strong acids to clear any mistakes and imperfections in the stone. 
7. Wait a minute to let the stone etch with the acid and proceed to stretch down or wipe down the stone with a cheese cloth. 
8.  Clean the stone with lithotine (Put on gloves!)
9. Take ashphaultum (Keep your gloves on!)  on a paper towel and rub on to the stone until the liquid is even. 
10. Take a sponge with water and wipe down the stone. your image should return and look the same as it did before you removed the crayon. The Ashphaultum allows the ink to stick on the stone. 
11. Prepare a slab of ink and roll it up
12. wet the stone and roll the roller 3x over the stone to apply ink. Repeat 3 more times. 
13. Proceed to re-etch the stone with 1/2 the drops of acid in each container of Straight gum
14. Re-ink and proceed to printing. 

How to Levigate a stone!

1. Begin with a lime stone slab.
2. have stone on level sink with grates. 
3. Wet stone with cold water
4. take #80 carborundum grit or 100# and put it ontop of the stone.
5. place levigator ontop of stone. begin to spin the levigator
6. follow a pattern with the levigator to ensure an even surface
7. Proceed to repeat this process 3x  with each grit - 80, 100, 120, 220.
8. once done, take a squeegee and wipe off excess water.
9. Take leather fan, and dry stone.
10. Take a steel straight edge and paper towel,  and measure if the stone is level on each plane if the paper towel moves after a tug, re-levigate the stone. 
11. take a file and file down the edges
12. stone is now ready for etching.

How to SCREEN PRINT

After exposing a screen time to begin to print.

1. Take the screen and place it flat side down on the table clamps and secure with the wing nuts.
2. Tape off edges of screen on the side facing up and tape off additional images that wont be used in a certain pull.
3. Find an appropriate sized squeegee.
4. With inks chosen and mixed-lift the screen, pour plenty of ink on the bottom half of the screen. 
5. Pull squeegee to the top half and flood the screen with it still lifted and then place down on paper. 
6. proceed to pull the squeegee in the opposite with a bit of weight
7. Lift screen
8. get print

If an edition is being done, between step one and two, Place your paper down and place pins down and tape them down. Proceed to match tabs and paper with the pins and repeat. Use one done piece to use as a template. 

INKS and Shiny things

Screenprinting inks vary. 

Speedball produces a water based acrylic ink in where its quite opaque but does not need modifiers out of the jar. But to create lighter or darker colors with transparancy- add a base modifier.  They also produce a textile ink that is also water based. 

jacquard produces a comperable ink as well, but they have an expanded specialty of metalic and pearlescent colors in ink and powder. 

Powders can be applied ontop of wet ink as another layer or mixed into the ink to change the ink color.

Always add base to INK to make it transparent versus adding white which ends up being very opaque. 

Making Films

To make films for screen printing-

use paint pens- use BLACK Sharpie Paint Pens those are the most opaque. The Sakura Deco markers are just as good, but they are a bit more expensive. 

So why Black? 

Light wont go through the black parts on the film. It wont allow the emulsion to harden and block off what isn’t going to be printed. Keep in mind to keep lines dark especially with fine point pens, occasionally those pens wont get as dark. 

Keep in mind

When making films, to make sure that everything is being thought as a stencil. Or even comparing to other things such as layers in photoshop. Each film is a different layer and a new image that goes on top of the next.

HOW TO EXPOSE A SCREEN!

1. Take a screen
2. Take a scoop coater and fill with emulsion.
3. Put scoop coater at bottom of screen, press down and pull up.
4. Make sure the emulsion is not too thick. If any excess- remove with paper squeegee.
5. Leave to dry in dark closet with a fan. 
6. Take the films and place them on the exposure unit facing up. Dont flip the image other wise it will turn out reversed.
7. Take the screen and put it flat side down over the films.
8. Close the exposure unit and set it for X time.
9. Take screen to wash out area, and on low flow with the power washer rinse the emulsion. The image should now appear. 
10. Let screen dry. 

TIMES: Mylar: 70sec    Clear film: 40-50sec  ink jet film(grey tint): 50sec