The Technique Freak Has a Challenging Week

AKA, how to triumph over the Devil, or his close relative, Almost Infinite Variables.

Having explained the intaglio printing process in a previous post, it can be more easily understood that there are variables in each step of the way in the printing of a matrix. And that’s aside from all the variables of producing the matrix in the first place.

Part of the appeal of printmaking for me has always been the technical, manual and mechanical aspects of the process of producing a print. I take a certain amount of pride in that process, and enjoy being able to make an edition of the highest standard I’m capable of producing. Part of this is learning, with each new plate, what the variables are in the process to produce the best image, and then being able to replicate it as closely as possible.

A few weeks ago I came to the point where I was happy with three etched copper plates, the first in a set of twelve, and wanted to start editioning them, having previous proofed each on different days in the studio. To edition a plate is when the artist gets to the point where it’s time to start making multiple prints without making any more changes to the matrix, ie, an edition of that plate in that state. However, the notion of what an ‘edition’ can be – limited, open, numbered, not numbered, etc – is really the topic of another post. The salient point is that the plates were at the stage where I was happy to want to make multiple prints.

The first step, then, is to pull a proof of each matrix to see what the image is going to look like, and to see if the plate is giving a satisfactory result. I went through the intaglio printing process and pulled a proof off each plate. Lo, there was a technical problem – it looked as though some of the ink wasn’t coming out of the grooves and onto the paper. There were gaps here and there where ink should be.

 

WM Compare gaps details
Above: proofs pulled from the three plates, showing approximately the same areas on the plate, where the ink is not transferring properly

 

At this point, there is a list of possible problems to work through:

Is the plate clean (excess grease, oil, or dried ink left over from the last printing session)?
Is there any foreign matter in the ink (dust, dried ink, anything which may hinder inking up)?
Am I inking the plate correctly (ie, getting ink into all the grooves when inking up)?
Am I overwiping the plate (ie, taking too much ink off when wiping)?
Is the paper too dry or too wet (as either state will affect the transfer of ink)?
Am I using the right sort of paper (high/all rag content, not sized)?
Is the press at the right pressure (too little pressure will not sufficiently transfer the ink)?
Is there the right amount of blankets on the press (affecting how the paper is forced into the matrix)?

As far as I could tell, there were no issues with what I was doing, but to get some perspective, I consulted several fellow printmakers and the head of department for some advice. I went through the process again for one plate with them watching as we chatted, to make sure I was, in fact, doing everything right. I pulled another proof… with the same results.

 

WM Rose plate - compare two plates
Above: first and second proofs from the same plate, showing how the ink is not transferring consistently

 

Now there were two prints of the same plate to compare, because other questions can arise, the chief one which seemed pertinent to this issue being: Are the gaps in the same place? If they are, this meant something wrong with the actual plate – the linework might not be holding ink in the first place, even though it looks like it is. Due to the ground on these plates being thicker than I had hoped, there were actually a couple of places where the lines hadn’t been scribed through the ground cleanly, and therefore perhaps hadn’t bitten properly.

 

WM Pear plate - compare gap with etching error - 3217
Above: areas such as the leaf, and some of the dotwork, have not been bitten onto the plate properly, and cannot hold ink in the groove to the same depth as a well-bitten line. The texture is different to where there is ink not transferring to the paper, such as along the horizontal lines at the bottom

 

However, in general, the gaps in the linework were in different places. I pulled proofs of the other plates in question, and the same result – gaps in different places, so it wasn’t the plates.

The only possible changes anyone could suggest at this point was to use one of the other intaglio presses, and to use a different ink. I was using the 3rd best press as the other two were being used for other purposes that day, and I was actually using what we call ‘House Black’, which is the ink supplied by department. It is a very basic, warm black intaglio ink which has a very simple base of oil varnish and pigment, similar to the first intaglios inks. But by this stage it was home time, so I hied me off to clean up.

Second day, more experimenting. I found the tin of Gamblin ink that had been bought a while ago and forgotten about, and moved onto the Number 2 press, as Number 1 was being used for an enormous linocut. Each of the three plates were inked up under the watchful eye of our fearless leader as we chatted, who was somewhat intrigued by the problem. Then we ran them through Number 2 and the result was – almost no gaps. Hooray!

But now with added plate tone. Not so much hooray!

Plate tone is when there are still the remnants of ink on the wiped surface of an intaglio matrix, in this case, etched plates. Each artist chooses how much plate tone they want to leave, and that also varies from plate to plate, image to image, depending on the artist’s intent and desire, and also their skill and ability. In this case, however, no plate tone was wanted. A very little would be acceptable, but this was excessive and really not what I wanted to see, especially as there was no hint of this happening during the previous printing sessions.

 

WM Comparing plate tone - none and too much
Above top: first proof with the inked line problem, but no plate tone, and below: third proof with less inked line problem, too much plate tone.

 

Plate tone can be due to a number of reasons, including:

How clean the plate is – is there excess grease or oil on the plate to start with?
How the plate is wiped – has the surface been wiped as clean as possible (without overwiping)?
The paper used – some papers pick up more or less detail, depending on rag content and/or sizing
The ink used – inks have different ratios of ingredients, making them tackier/oilier/dryer, giving different results
The pressure of the press – higher pressure will force more ink off the plate onto the paper

The paper I was using was Hahnemuhle, which is generally considered to be the finest quality intaglio paper. One of the characteristics of this paper is that it picks up every detail, and while in this case it was working to my disadvantage, it remained the paper of choice. My wiping had not changed from each of the sessions. The pressure on the press looked all right, perhaps a little higher than usual, but not too high. Everyone had suggested that the Gamblin ink would be better than the House Black.

The next conclusion was that perhaps I should Brasso the plates to ensure they really were as clean as possible. Cleaning with Brasso is very similar to the process of degreasing a matrix using ammonia and whiting – it cleans and polishes the copper, not only removing any traces of oils and solvents, but also gently buffing out some of the tiny surface marks.

And so the three plates were Brasso-ed, and printed again. The result: almost, but not quite, exactly the same amount of plate tone as before, just more even due to the clean surface.

 

WM Compare before and after brasso
Above top: third proof before Brasso and below: fourth proof after Brasso, both showing too much plate tone, but more even tone after cleaning

 

At this point, I had been printing all day. It was time to take a break and think hard.

I suspected the Gamblin ink was not the right ink for the job. It’s a very nice ink, but has a different texture, hard to describe, but almost grippy and slightly plastic. I wondered if it has either a higher rosin content or a modern plasticizer content, which alters the way it spreads and wipes.

I was very happy with Hahnemuhle paper, despite its characteristic of taking up every detail.

I felt the pressure of the press could have been a little bit high, which could have been part of the problem. Because the copper plate is very slightly thinner than a modern plastic-backed zinc plate, I had also packed the back with a couple of layers of newsprint, and perhaps this was unwarranted.

I also mulled over a series of modern intaglio prints I did about a decade ago. It involved making my own inks with ground pigments, linseed oil, and relief transparent medium (a thick, transparent ‘ink’ used to carry pigments or to reduce the intensity of existing inks without altering the tone), and the alteration to the wiping process I developed for those plates.

In modern practice, most people use the thin, smooth pages of an old phone book for the final wipe, but I had noticed that this affected the final colour of my prints – there was, in fact, a transfer of ink from the phone book page to the printing plate, and subsequently to the print. I would mix a beautiful, clear colour on the slab and have it turn slightly muddy when it was printed. So I developed my own method of the final wipe with white, acid-free tissue (usually bought for layering and storing prints), and the problem was resolved.

According to Ad Stijnman in Engraving and Etching, in early printing practice, the final wipe may have been the heel of the hand with a thin coat of whiting, or it may have been a very fine, soft cloth. I have tried hand-finishing, but given the modern attitude towards potentially harmful chemical exposure through absorption, this is not necessarily the way to go.

For these particular plates, on previous days of proofing, I had tried normal modern wiping; wiping with a soft cloth (probably not the best sort, but the best available in the studio on the day); and no final wipe at all, just finishing with tarlatan. It was now time to add tissue wiping to the list.

Finally there was another plan of attack: Same paper, back to House Black ink, slightly less pressure on the press (plus taking one sheet of newsprint out from underneath the plate), and final wipe with tissue.

The next available day, I was back into the studio to put this into action.

And it more or less worked – I achieved a near-perfect print, a very few almost imperceptible gaps in unobtrusive places, and an acceptable hint of plate tone.

 

WM Rose plate - gaps - tone - best result
Above: First, fourth and fifth proofs, with the fifth being a happy medium between good line printing and slight plate tone

 

Happy printmaker dance ensued. And the promise of lots of printing.

 

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