Tuesday, July 21, 2009

Quick Stuff

Wet Wash
(To clean up the plate, remove grease spots and marks)
Sponge off the gum film. Keeping the plate wet, wash out the ink with lithotine (put a tiny bit of asphaltum on the rag to protect the shellac). After all the ink has lifted out, wipe with a wet rag and then with a dry. Clean any remaining debris with the sponge, keep the plate wet and roll up to full. Continue printing or store.

Hot Gum Deletion
(To remove an area of the drawing)
Through a gum mask, remove the ink with lithotine. Remove the shellac with acetone and lacquer thinner until it is completely gone (it will, however, leave a stain of the shellac color). Tape a mylar to the surface, mark what deletions you wish to make. Slip an iron oxide paper under the mylar and trace your deletions onto the plate. Mix a VERY hot etch (something like 1oz tapem plus 10-18 additional drops of phosphoric acid). Note: test the pH of the etch. If it's too hot, it becomes a counteretch (at less than 1.5 pH) and will reverse the chemistry of the plate. Apply the etch to the areas you want to remove (this works well for large flat areas) and let the etch dry on the plate for at least one hour. You can also heat set the etch with a heat gun. After the etch cures, put on a new shellac film (0ver the etch) and bake for 5 min. Process any lacquer and shellac changes through a 50/50 mask to keep the shellac from sticking to the borders. Buff in asphaltum, wash off gum film, roll up with black. Fan dry, dust with talc. Massage in gum mixed with a little scouring powder (0nly on the border). Wash off with water, fan dry, spot clean the borders with acetone. Ready to print or put into storage. 

Calendaring Paper
(whaaaat the hell)
Calendaring is the process of putting every sheet of printing paper through the press before editioning to account for the stretching of the paper when placed under pressure. If you calendar first, your registration will be more accurate. Orient the paper the way you will print, with the leading edge entering the press first. At 3/4 printing pressure, run the paper through under a tympan and newsprint 2 or 3 times in the direction of printing. Don't go back and forth, this will disturb the fibers. Calendar before adding any registration marks and especially before punching for registration pins.

Counteretch on Plate
(to add more drawing materials)
Wash off the gum mask at the graining sink, being very very thorough. Pout a little counteretch on the open area you want to add to, rub in the counteretch to physically dislodge the gum particles, about 1.5 min. Rinse with water, repeat. (Never pour counteretch onto a dry plate, it should always be wet first). (White vinegar in a six parts water one part vinegar mixture will work too) Blot with newsprint, fan dry. Add new drawing materials and etch at 1/2 strength. (You'll have to change the shellac)

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