Print Process

Part of Printing

An end-to-end guide to the complete letterpress printing process from manuscript to finished printed sheet.

Why This Matters

Understanding the complete print process — not just individual steps in isolation — allows a community to plan, resource, and execute book production effectively. Each stage feeds into the next; a mistake or shortage at any point cascades through everything downstream. The printer who understands the whole process can anticipate bottlenecks, stage work efficiently, and troubleshoot problems before they waste precious paper and ink.

Letterpress printing is a systems skill. The same person need not perform every step — a community might have a compositor, a pressman, and a binder — but someone must understand how all the pieces fit together. That systems understanding is what this article provides.

Stage 1: Manuscript Preparation

Before any typesetting begins, the text must be prepared in a clean, accurate form. Corrections after type is set are expensive (time-consuming), so eliminate all errors before the compositor begins work.

Copy preparation:

• Write or transcribe the text in clear, legible script, with consistent spacing.
• Mark all formatting decisions: headings, emphasized text, paragraph spacing, special characters.
• Note the intended page size, type size, and column width.
• Calculate the approximate number of pages the text will fill at the intended type size and measure. This determines how much paper to prepare and how many type characters will be needed.

Casting off: Estimating the number of pages that text will fill before setting it is called casting off. Count the average number of characters per line in the manuscript, multiply by the number of lines, and divide by the characters per page at the intended type size and line spacing. This calculation becomes more accurate with experience.

Stage 2: Type Preparation

The compositor must have sufficient type of the correct face and size available before beginning to set. Type must be clean — free of ink buildup, damage, and mixed sorts from other fonts.

Distributing type: After any previous print run, used type is cleaned and returned to its cases. This “distribution” step is critical: type stored mixed or dirty cannot be reliably typeset. Distribution is done character by character, examining each piece and returning it to the correct compartment in the type case.

Checking type supply: Count the number of each character available and compare to estimated usage. Common characters (e, a, t, o, n) exhaust quickly; plan accordingly or cast additional sorts from the hand mold before setting begins.

Stage 3: Typesetting (Composition)

The compositor sets type one character at a time into a composing stick set to the correct line length (the “measure”). Characters come from the type case with the right hand and are dropped into the stick, which is held in the left.

Setting: Each character is placed upright in the stick with its nick (a small groove on the type body) facing up and toward the compositor. Characters are set in reading order, left to right. Spaces between words are added from a supply of blank spacing sorts.

Justification: Each line must be filled to the exact measure. The compositor adjusts spacing between words to fill the line. This is the most skill-dependent part of typesetting — good justification produces lines that are all the same optical density; poor justification produces rivers (vertical white channels running through the page) or overly tight lines.

Proofing: After setting several lines, transfer the type to a galley (a three-sided flat tray) and pull a rough proof impression on a spare piece of paper. Read the proof against the manuscript for errors. Correct errors by removing wrong characters and replacing them. This proofreading step is much faster than correcting errors after the type is made up into pages.

Making up pages: After proofreading, the compositor assembles lines of type into pages, adding spacing for headings, paragraph gaps, page numbers, and running headers. Pages are built up in a galley or on the imposing stone (a flat surface).

Stage 4: Imposition

Multiple pages are assembled into a single form that will print on one side of a sheet. When folded, the pages must appear in the correct sequence. This arrangement is called imposition.

Imposition must be planned before typesetting begins (so pages are numbered correctly) and executed carefully when locking up the form. See Folding and Gathering for imposition schemes.

Locking up: Pages are arranged on the imposing stone in the correct imposition pattern, surrounded by furniture (blocks of wood or metal that fill spaces between pages) and locked into a metal chase with a quoin (a wedge that tightens by tapping). The locked-up form is called a forme.

Test lock-up: lift the chase slightly from the stone. All type should stay in place without any looseness. Any movement indicates the lock-up is inadequate. Re-lock before attempting to print.

Stage 5: Press Make-Ready

Before printing the full run, the press must be prepared:

1. Check and adjust platen alignment (see Platen Design).
2. Build the tympan packing to the correct thickness.
3. Set registration points for paper alignment.
4. Load ink on the disc or slab and condition it to correct consistency (see Ink Consistency).
5. Charge the ink balls or roller.
6. Pull a test impression and inspect it critically.
7. Perform makeready — adjust packing to achieve even impression across the entire form.
8. Pull a final proof. Have it checked against the manuscript by someone other than the compositor if possible.
9. Receive sign-off before committing to the print run.

This preparation phase takes 30 minutes to an hour for a typical form. Rushing make-ready wastes time overall — each bad impression during a long print run represents wasted paper and ink.

Stage 6: Printing the Run

With the press correctly made ready, printing the run is systematic repetitive work. For each impression:

1. Re-ink the form (balls or roller).
2. Position paper on the tympan, seat on registration points.
3. Close the frisket.
4. Apply impression pressure.
5. Release pressure.
6. Open frisket and tympan, remove printed sheet.
7. Lay sheet to dry.
8. Repeat.

Monitoring during the run: Pull a complete inspection sheet every 25–50 impressions. Check for:

• Ink level (add from reserve as needed)
• Type movement or slippage (listen for any change in the feel or sound of the impression)
• Registration drift (paper consistently shifted slightly off-position)
• Ink consistency changes (temperature changes affect ink)

Two-sided printing: Most book printing requires printing both sides of each sheet. The second side is called the “reiteration” or “retiration.” Allow the first side to dry completely before printing the second — at minimum 12–24 hours for oil-based ink, longer in cold or damp conditions. Wet ink on the back of a sheet offsets onto the tympan during retiration, contaminating subsequent impressions.

Stage 7: Drying and Inspection

After printing each side, lay sheets individually to dry. Do not stack wet sheets.

Once dry, inspect every sheet:

• Any sheet with severe smearing, misregistration, or missing areas should be flagged for possible reprinting.
• Minor defects (slight ink variation, very small misregistration) are usually acceptable.

Calculate whether enough perfect or near-perfect sheets exist for the intended run. For a book edition of 50 copies, you need 50 good sheets of each signature. If any signature is short, reprint just the missing quantity before moving to binding.

Stage 8: Binding

After all sheets are printed, dried, and inspected, they move to the bindery. See Bindery Operations for the complete binding workflow.

Workflow Scheduling

Understanding the timing of each stage allows a print shop to work efficiently:

Stage	Time Required	Bottleneck
Manuscript preparation	Variable	Author/scribe
Type preparation	30–60 min	Distribution backlog
Typesetting	1,000–1,500 characters/hour	Compositor skill
Imposition and lockup	30–60 min	Planning
Make-ready	30–60 min	Press setup skill
Printing (per side, per sheet)	~15–20 sec	Press speed
Drying between sides	12–24 hours	Fixed
Binding (per book)	3–4 hours over 1–2 days	Drying time

For a 100-page book in an edition of 50 copies: expect 2–3 days of typesetting, 1–2 days of press work (including both sides of all sheets), 1–2 days for binding. Planning around drying times — keeping the press busy while sheets dry, and staging binding work in parallel — is the key to efficient output.