Post-press and finishing: cutting, folding, binding, laminating, die-cutting, QC
What the exam tests
Finishing questions test the sequence from printed sheet to delivered product - cutting, folding, binding, laminating and die-cutting - plus the checks that prove the job is right.
Cutting and folding
- Guillotine order: cut the gripper edge first, then the opposite edge, then the sides. Trim marks and 3 mm bleed are useless if the sheet is cut before folding.
- Folding: parallel (buckle or knife), cross and right-angle. Every extra fold multiplies thickness at the spine.
- Grain must run parallel to the fold; coated board needs scoring before folding.
Binding
- Saddle stitch: wire through the spine, roughly 8–64 pages, lies flat; creep must be compensated on inner sections.
- Perfect binding: glued spine from about 40 pages up; needs a rough, notched spine and grain parallel to the spine. PUR gives the strongest film.
- Wire-o and spiral lie flat and suit manuals; case binding for hardback books.
Laminating and die-cutting
- BOPP gloss or matt, thermal or wet lamination, adds stiffness and scuff resistance but complicates recycling and can curl a thin sheet.
- Die-cutting uses a steel-rule die carrying cutting rules and crease rules on the same forme; nicks hold the waste until stripping.
Quality control
Check register, colour against the approved proof with a densitometer, trim to the specified size, crease quality, ink adhesion (rub or tape test) and count against the delivery note.
Worked example
A 64-page saddle-stitched brochure on 0.10 mm paper.
- Leaves per copy = 64 ÷ 2 = 32.
- The inner leaves push out by roughly half the section thickness: 32 × 0.10 ÷ 2 = 1.6 mm of creep.
- Set creep compensation of about 1.6 mm across the spine and allow extra fore-edge trim, or the inner pages will be short after trimming.
Traps that cost marks
- Folding against the grain, then blaming the stock.
- Forgetting creep on thick saddle-stitched work.
- Creasing with a cutting rule instead of a crease rule.
- Laminating before the ink is fully cured, causing blistering or delamination.
- Trimming to final size before binding, then finding the spine out of square.