Tuesday, November 26, 2013

Registration of Multiple Plates

I learned this wonderful registration technique for printing multiple plates at Highpoint and I will be forever grateful. It increased the rate of successfully registered prints considerably. I'm not sure which clever mind invented this registration jig, but I believe my sources got it from Crown Point Press, so I'll refer you to their blog on how to make a registration jig. (I wasn't successful cutting my jig on the jump cutter, so I got someone to cut it for me with a diamond blade. It was quite jagged afterwards, but easy to smooth with a file). The jig consists of two L-shaped copper pieces. The narrower one, or registration bar, is taped onto the press bed with double-sided tape.

The second one, which should be at least as wide as your paper border, is a removable jig.

Every time I put my plate on the press bed, I place it into the jig, which ensures all plates are always in exactly the same spot. I keep the paper trapped under the roller when I change the plates, i.e. the paper never moves and the plates are always in place. This system is pretty much fool proof!

Proofing the Plates - Progress Report Four of My Minneapolis

I finished etching my plates and I've had to wait a while to get my turn at the big press. The studio has been busy lately and with my two plates taking up so much space, I wanted to wait till I had a quiet day so as not to be in anyone's way. To know how the etching has turned out, I need to pull a test print, or proof. I proofed both plates together last Friday. Unfortunately the print didn't come out very nicely for various reasons (I should know by now that I must proof on the editioning paper, but I had a sheet from the same brand only with slightly more surface texture that I wanted to use up...frugal me also used inks I had saved from printing before...anyways, the ink wasn't good and the paper didn't take the ink well, so the image came out rather washed out, streaky and blotchy).

The one good things I was able to discern on this proof was the registration of the two plates: it's working fine! I was afraid some stretching of such a large sheet of paper might become an issue. The colours need some adjusting, but they also might change if the keyplate prints better. I wasn't sure if some of the flaws in my print were errors in the aquatints, but a second proofing of the key plate with straight black ink on Monday showed me - to my huge relief - the plate is fine. While too dark and contrasty at this point, I can now burnish and edit my plate as well as adjust the ink's density by adding transparent base. With the grey and black printing properly now, the green won't come through as brightly on the next proof. 

If you're not familiar with Intaglio printing or etching, I'll briefly describe the inking of the plates here. With a small rubber squeegee, I spread the printmaking ink over the whole surface of the etched and cleaned plate taking care to fill all the little etched lines and grooves. I carefully scrape off most of the excess ink. 

Then I carefully wipe the surface with a bunched up piece of tarlatan (cheese cloth) to remove any ink from the surface without taking the ink out of the etched grooves. I will talk more about the colour printing with the stencil a different time.

Tuesday, November 12, 2013

Stage-biting Aquatints - Progress Report Three on My Minneapolis

For the past three weeks I've been working on the aquatints on my two plates. Aquatints are all the solid colour and tonal areas in an intaglio print. To prepare the plate for an aquatint, I have to degrease it really well. Next, I have to drop rosin onto the plate, which I do in a large rosin box, which is a wooden box with a fan at the bottom and a few tablespoons of rosin powder inside. After turning on the fan briefly, the rosin is suspended inside the box; I place my plate inside and let the dust settle for a certain amount of time (approximately five minutes). When I take the plate out again, I have an even, thin layer of dust of on the surface. The copper plate then goes on a hotplate where the rosin melts onto the surface. Wherever one of the rosin-dust grains melts to the plate, it will resist the acid. The acid, therefore, will bite between all the microscopically small dust grains creating a fine dot pattern or small pits that will later hold the ink. This is where the stage-biting starts, meaning I etch the plate in intervals while stopping out parts that are etched long enough. Once the plate has the rosin on the surface, for example, I stop out (paint with asphaltum) all the areas I want to remain white or don't want to hold any tone (see image above). Then I etch the plate for the first stage at 15 seconds for a really light grey, take it out of the acid, rinse it off, stop out all the areas I want to keep at the lightest grey. 

Then I etch the next stage, doubling the time for my next tone and I repeat this process until I have etched about seven stages, which will give me a nice range of tones from very light to medium tone to a rich black or a deep colour (so, I etch 15 sec, 30sec, 1min., 2min., 4min., 8min., 16min.). Below is a detail after the 1 minute etch. I do this whole process on both plates, etching different areas on each plate which will hopefully work well together once they overlap.

Working on two plates makes it a bit tricky to think about where the colours will go and where colours will overlap with greys to create different tones. I've made a colour map by painting water colours onto my line-etch. While it's pretty ugly at this stage and the colours aren't quite true to the etching inks, this map does help me to visualize the colours and tones as I work my way through the different stage-bites. I'm planning on wiping two colours à la poupée on the key plate and two or three colours on my second plate, possibly adding a stencil roll as well, that's why you see so many colours in my sketch. This might change later as I edit the plate. I'm also planning on doing some soap ground or spit bite in the blank area in the center. 

Friday, November 8, 2013

Needling, Etching, Proofing - Progress Report Two of My Minneapolis

Once the drawing is done, I prepare the copper plates for a transfer. To polish the plates, this time I borrowed a fellow printmaker's orbital sander which he had outfitted with an old piece of printing felt instead of sandpaper to which I applied jewellers' rouge and oil for a final polish. It worked like a charm and saved a ton of time on those two large plates (I need to get one of my own!!!). After the polishing, a hard ground (asphaltum) is evenly and thinly brushed onto the surface of the plate. This brownish-black and shiny coating will protect the copper in the acid. Transferring the pencil drawing is really easy at this point. Once the asphaltum is dry, I simply run the plate with the drawing through the printing press and the graphite transfers beautifully onto the black surface without smudging. In late September I started needling the plate, meaning that I draw the whole image with a steel needle (I also like to use my burnisher for thicker, bolder lines) through the asphaltum layer. Where the copper is exposed, the acid will bite and therefore create my line etch. In this close-up of my plate you can see part of the graphite transfer and part of the already needled lines.

Once the plate is etched, I strip the asphaltum from the surface. Left are all the etched lines in the plate, which I then fill with a special printing ink, polish the surface of the plate clean and run it through the press with a sheet of damp paper overtop. Voilá! I have the first proof of my line etch (click on image to enlarge).

Since My Minneapolis will be a colour print, I need a second plate which will hold the colour. My first plate, the key plate, will hold all the black lines and any grey-black tones or aquatints (more about that later). For the colour plate to line up with my key plate, I need to use a good registration system (more about that also later) that will ensure that both plates will always overlap properly and 'match up' correctly. For this to work, I transfer the key image onto my second plate. As soon as I pull the first proof, I exchange the just printed plate on the press bed with my second plate that is coated with the asphaltum. I then run the still damp paper with the fresh print through the press again on top of my second and blank plate. The wet ink offsets onto the plate and I can start needling the lines on plate two which will be my guides for where I want all my colour areas to go. The offset black ink is clearly visible on the asphaltum as you can see in the detail below. Now I have to draw (parts of) the image for a third time. Usually I etch the lines on the colour plate really lightly simply to be guides for the colour aquatints later. 

Thursday, November 7, 2013

Drawing - Progress Report One on My Minneapolis

Since my new piece is taking so long to finish, I've decided to share some of the early stages and the process that's involved in creating the etching plates with you. In early September I started working on a drawing for a print about Minneapolis. After two years of living here I have established some connections with the place that allow me to create a map of all the things and landmarks that are significant to me. I did a lot of biking around in late summer to take photographs of buildings, bridges, parks, as reference images. I started on the Greenway, which runs just a few blocks from our place (it's the most amazing double-laned bike highway running east to west through the city along old railroad tracks...hardly any lights or stop just go go go), across the Sabo bridge (cyclists' bridge alone!)  to the Mississippi river, up along the river to the St. Anthony Falls and the Stone Arch Bridge, through downtown and back. With all the things I wanted to include in the piece, it got rather large, but since I've always wanted to try to work at this scale, I decided to go for it, especially since I have access to a large rosin box and acid bath here at Highpoint. The plates are 24" x 36" (60cm x 90cm)...yes, you read correctly, 'plates': this will be a double plate print. I hope it's going to work the way I imagine it. I struggled a lot with the layout of the image and since the scale and the placement of various elements kept changing, I opted for cut out sketches that I was able to move around, scan, enlarge or reduce in size until I was happy with the overall image. To me this is the same process as editing a text. I have a first draft; then I start to edit and shift things around until things look and feel right. The process is far from over before I can show a final piece of art.