Pick: Unwanted spot, not a tool

Most people think of a pick as a tool: an ice pick, a guitar pick, or the pointed end of a pickaxe. A pick is something you use to break, scrape, or pluck. The verb means to choose, gather, or extract. None of these senses enter the printing shop.

In industrial printing, a pick is a defect, and a serious one. It occurs when a particle of ink or paper becomes trapped in the hollow of a letterform, the sunken cavity that holds ink during a print run. The particle fills that cavity partly or wholly. When the inked form presses onto paper, the pick sits slightly proud of the letterface, or blocks ink from flowing evenly. The result is a spot, blotch, or uneven area on every sheet printed until the pick is cleared. In high-volume work, a single pick can ruin thousands of copies.

The source of a pick is usually paper fibres, dust, or dried ink already on the press. Modern printing inks are thick and tacky, and they collect debris. The letterforms themselves are tiny and intricate, especially in small point sizes. When the forme sits on the platen or cylinder, capillary action draws particles into the hollows. Pressroom staff must clean the forme regularly, using brushes, solvents, or compressed air.

The term "pick" carries the same fragment-lodged-in-a-cavity sense across several trades. In metalworking, a pickle is a chemical bath, not a preserved vegetable, because the acid eats away burnt surface layers that have become embedded during casting. In mining, a rockpicker removes unwanted stone fragments from ore. In textile manufacture, a mispick is a yarn that lands in the wrong place in the weave, and a pick is a single pass of the shuttle across the loom carrying the weft thread. In all these contexts, the word originates in the idea of selecting, placing, or lodging something into or onto a surface, whether by tool, by accident, or by design.