On the black ink

The black I print with started life as a commercial Van Son rubber-base black, but it has been adulterated so many times over the years that I would not call it Van Son any more. The current recipe is a blend of Van Son 800 rubber-base, a small quantity of carbon black powder (added a teaspoon at a time, mixed in by hand with a small ink knife), a few drops of cobalt drier, and, this is the part that took years to settle on, a quantity of boiled linseed oil sufficient to give the ink a particular tackiness that I can only describe by feel.

Why bother? Letterpress and offset are physically different processes. Offset printing puts a thin layer of ink onto a sheet via a rubber blanket; letterpress puts a slightly thicker layer of ink directly onto a sheet, with the paper compressed into the type. The result is that letterpress ink sits in the paper rather than on the paper, and the visual difference is striking. A letterpress black is darker than an offset black because it has more pigment per area, and the pigment is distributed unevenly into the paper's surface in a way that catches light slightly. You can see this if you put a letterpress print and a laser print side by side under raking light. The letterpress print has a small but visible relief; the laser print is flat.

Letterpress ink sits in the paper rather than on the paper. The black is darker because the pigment is distributed unevenly into the paper's surface in a way that catches light slightly.

The recipe (current as of 2024)

• Van Son 800 rubber-base, 1500 ml
• Carbon black powder, about three level teaspoons
• Cobalt drier, six drops
• Boiled linseed oil, about 50 ml, added slowly, mixed continuously, until the ink draws a string about four centimetres long when lifted with the ink knife

I mix it in a 2-litre stainless steel bowl with a flat-bladed ink knife. The mixing takes about forty minutes. The result fills four 500 ml ink cans, sealed with food-grade wax paper under the lids, that last me about eight weeks at the workshop's normal printing rate.

Why not just buy ink

I have, in the past, simply bought ink. Commercial letterpress ink is reasonably good. But after the first eighteen months of running the workshop, I noticed something: the prints that came out of commercial ink looked, side by side with the prints I had pulled with hand-mixed ink, slightly more even. The commercial ink behaves predictably. The hand-mixed ink behaves slightly less predictably, and the slight unpredictability, the variation in tackiness from sheet to sheet, the small density shifts across a run, gives the prints a quality that I have come to think of as warmth.

This is, I am aware, the sort of claim that letterpress printers make about everything we do. We tend to overstate the differences. But I have done the experiment with my own eyes, a hundred prints of a single page, fifty in commercial ink and fifty in hand-mixed, and I can pick out the hand-mixed sheets from across the studio. So I have continued to mix.

The smell

The smell of fresh letterpress ink is one of the things people who do not work with ink underestimate. It is a complex smell, linseed, slightly nutty, with a faint metallic note from the carbon, and after nine years I can no longer enter the workshop without breathing it in deliberately. When the workshop closed in 2024, the smell took about three weeks to fade from the loft. I went up there on a quiet afternoon in May, after the press had gone, and the room still smelled faintly of ink. The next time I went up, in June, it was gone.