Printmaking (Series 11 of 21) - Using a subplate for rolling up a plate

By Nik Semenoff August 16, 2004

} Using a subplate for rolling up a plate Printmaking Series - Part 11 of 21 By Nik Semenoff When rolling up a plate in traditional lithography, it is done on the press bed. The roller covers the plate, going over the edges and unto the press bed. This leaves ink all around the plate, which has to be cleaned up at the end of the session. One has to be very careful and not get any of this ink on prints. In keeping with making the studio safer, I started to use a subplate covered with silicone for rollup on a table next to the press. There are a number of ways to make a usable subplate and each have their purpose. In my own studio I use a sheet of surplus ¼" plate glass that I have grained with a levigator, like graining a stone. Care must be taken at the edges or the heavy weight will crack the glass. The grained surface is perfect for the silicone as caulking material is designed to bond to glass. Cover the entire surface with diluted silicone at the same consistency you use it for plates. A couple of coats will give you a durable subplate, which can be resurfaced from time to time. For classrooms, glass would not be a safe material to use. At our university I have used sheets of hardboard as they cannot be broken. Masonite comes with a smooth front surface, but the rough back side is the best for subplates. Use ¼" material cut to fit the table on which the rollup will take plate. I suggest making it a bit larger on the sides, overlapping the table so that strips of wood can be attached at the bottom to keep the Masonite from moving around during rollup. First you must seal the Masonite by mixing a batch of silicone much like you would use for plates. This is applied generously and spread evenly, then allowed to set overnight. Depending on the texture of the rough side, there may be a great number of wood fibers sticking out like hair. With a propane torch, singe these off by play the flame not directly at the surface, but along it. Now you can put on the main silicone layer. Prepare a 4-6 inch brayer by covering it with vinyl contact material so that it can be recovered for use again. Silicone would ruin the brayer if allowed to contact the rubber surface. Using a wide putty knife and silicone straight from the cartridge, spread a layer while pushing the material into any depression in the texture. You will have to do this under good ventilation as acetic acid is released and not safe or pleasant to smell. No matter how careful you are, there will be ridges left by the edge of the putty knife that have to be smoothed down. This is done by rolling all over the surface with the Mac Tac covered brayer - but this will leave an orange peel texture that you do not want. To smooth out the surface, use a damp cellulose sponge for this. Silicone will not stick to the wet sponge and you can push down the high points to get a perfect surface. You may need another coat after this dries, if the Masonite was too rough. A third method is to use old aluminium plates that are bigger than the printing ones. Two can be taped together on the back with the thin plastic binding type used for shipping packages. The plates are prepared as if for imaging, but the entire surface is siliconed to produce portable subplates if that is required. I know of institutions that use this concept in their class studios. I suppose a large sheet of industrial aluminium can be used in the same way for a classroom, instead of worrying about broken glass. ________________________________________________ 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.

• Posted: 2004-08-16