The StreamFolder™ system for shortrun books produces book blocks comprised of 4-panel or 6-panel signatures. The finished book blocks have extremely accurate page registration and the folding process reverses the natural paper curl every other sheet, resulting in very flat, premium quality books. The StreamFolder system provides unprecedented reliability for short-run digital book printing jobs of varying run lengths including ‘books of one.’ The StreamFolder folds the web once or twice enabling efficient use of a web-fed press at its maximum print width.
When compared to book blocks created from single cut sheets, the StreamFolder system’s signatures eliminate common problems coming from inevitable variations in paper quality. Slight changes in web width will not impact page registration with the StreamFolder system’s unique Z-fold design ensuring pages are always precisely registered to the spine edge. In addition, any paper curl is effectively canceled as pages are folded back against each other.
For 2-up printing, one fold station is used to simply fold the web in half. For 3-up printing, two fold stations are used to create a Z-fold. The Z-fold is a unique feature of the StreamFolder f20 and it provides substantial advantages versus competitive C-fold systems. Every roll of paper has slight variations in width. Only the StreamFolder’s Z-fold design can guarantee fixed page registration to the spine edge, regardless of these variations. The Z-fold forces web-width variations to the face edge which is cleanly trimmed during binding producing a superior quality book.