Art Articles & Reviews

} Converting traditional plates to waterless litho Printmaking Series - Part 19 of 21 By Nik Semenoff A printer may have problems printing an edition done with grease and gum etch as the image starts to darken. At other times the artist may like the look of grease tusche washes or grease crayons. It is possible to convert such surfaces to easier printing and more permanent plates. Nik Semenoff When the plate is drawn with grease material, and has been proofed, it could then be converted for printing in waterless. Normal methods are used but the etch need not be as strong as that can destroy the fine tints. After it is decided to make the conversion, the plate is gummed and the ink replaced with a vinyl lacquer base. Then the gum is removed, the plate slightly counter etched and silicone applied. After curing, the lacquer is removed with acetone and the plate printed. Now all the delicate tints can survive large editions if done properly. If you decide to do the image in grease materials and not worry about proofing with traditional methods, then you don't need to use a very acidified gum. In fact just plain gum is all that is necessary to produce a mask while the grease is removed and replaced with lacquer. The plate is then washed well with water and silicone put on the surface as before. While the normal vinyl print base can be used, I find that there are many others that will work as well and not as noxious. Nik Semenoff I have found that all commercial photo plates can be converted, both negative and positive types. These plates will have a strong images made up of lacquer and the usual gum etched surface. For conversion, the first thing is to remove the gum with water and a good counter etch solution - all gum must be removed. Depending on the type of lacquer, I advise washing the plate with sodium metasilicate as this produces a better bond with the silicone. Next silicone is applied and buffed to a smooth thin film. After curing, acetone is usually enough to remove the lacquer and reveal the metal for printing the image. Some negative plates have a lacquer that resists the acetone to completely be removed, but the silicone comes off the surface and the remaining lacquer accepts ink. These plates will print as if they were designed that way for waterless litho. ________________________________________________ Copyright © 2004 Nik Semenoff Nik Semenoff Artist-in-residence University of Saskatchewan Visit Nik Semenoff's website at duke.usask.ca/~semenoff/ for more information.