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Notes on Printmaking 3: Evolution




Etching on zinc plate

I don't even know what this is supposed to be. The Aurora Borealis was my starting idea for this piece but then it ended up looking like a mountain range with what appears to be funeral pyres. It's funny how the actual work differs greatly from the inspiration.

After drypoint with plexiglass we moved on to metal plate printmaking. When etching on a zinc plate you don't just start scratching away on the metal surface. Prepping begins by cutting the plate to size, then degreasing and polishing. The surface should then be evenly coated with either asphaltum or bitumen, acrid-smelling tar-like substances used to protect the plate from acid. Once the coating dries, you can now proceed to etching your design using a stylus. In the end you should have a plate with exposed parts making up the design as a result of stripping away the coating during etching.

Afterwards, soak the plate into a mixture of nitric acid and water. The acid will eat away at the parts not covered by the bitumen, essentially engraving your design onto the zinc plate. Soaking time will vary on the nitric acid/water ratio and how deep you want the design to be etched on the plate. It takes about an average of 30 minutes, but usually we tested for the 'bite' with the tip of the stylus. To complete the process,  remove the bitumen with lacquer thinner. Your plate is now ready for printing. 

Printing with a metal plate is the same as with acrylic. Get some paint, smooth it over the surface with a squeegeemake sure that the paint settles in the groovesand wipe away the excess. Run it through the press. The first image is the print result of my plate after following the basic metal plate printmaking process.

At this point it looks... bare. The plate lacks drama, as our mentor pointed out. I agree with him.



To add some depth we used a technique called aquatinting. The actual process we did was a shortcut, because apparently we need to use some sort of special aquatint machine which the studio does not have. For a more practical approach we made use of a can of spray paint. The idea is to evenly paint the surface but you can see from the top right-hand portion of the plate that I did a poor job and accidentally sprayed more on that area. The plate will then have tiny paint splats all over. The principle behind aquatinting is that once the plate is soaked in the acid, parts covered by the paint will be protected, which will lend the design some texture. 

To achieve the final design we did a repetitive process of coating the plate with bitumen and soaking it in acid. First we soaked the spray painted plate in the acid for five minutes, took it out, and covered areas with bitumen gradually from the bottom up. Tossed it again in the acid, waited a few minutes, took it out, covered more areas, and so on. You can see from the prints that the intensity of the texture becomes greater from the bottom up.

In case you wish to smooth over some areas on the plate, a tool called a burnisher is used, which I used to create the bonfire-like things and for highlighting some areas. The burnisher is also used to erase errant scratches in case there are some. It's not easy fixing mistakes and highlighting in metal platesto use the burnisher you need to have good upper arm strength if you intend to get the job done quickly.

The plate took about 8 hours from start to finish, and that's not including the actual printing. I will talk about printing techniques in a different post.

I know it's difficult to understand all the different printmaking methods and materials without visuals and I apologize for that. I'm not the type of person who takes photos of every move I make and thus documenting my work would be a conscious effort, something I always forget to do. Unfortunately this results in photos of only the final result, which in turn makes for wordy posts in an attempt to explain everything. I will be able to take photos of the studio and some works in progress of other people next year, when classes resume. Until then I hope the various print editions will make up for the gaps. Please tell me what you think of them, whether you like them, points for improvement, etc.

3 comments:

  1. Thank you for sharing this. It's very fascinating to read about the different stages of printmaking..

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