HP Indigo Troubleshooting – Printing Landscape FlexBind Sheets

Duplex printing the landscape FlexBind® products can require additional press optimization.  Since the FlexBind® hinge is on the short edge of the sheet, the flexible spine must be rigid enough to feed properly into the grippers on the impression cylinder. 

Most FlexBind® products have been RIT certified, verify that the landscape sheet being used has received the proper certification and follow any printing directions provided. 

Generally, it is recommended to run the product with the hinge trailing out of the drawer.  The patent pending gap stiffener technology on the FlexBind® sheet keeps the flexible spine in position to feed normally into the grippers.  Small variations in press calibration can have a significant impact on the duplexing of the sheet.  The timing sensors for the duplex grippers occasionally need attention to properly detect the landscape sheet. 

Below is a list of recommendations for jams related to running landscape FlexBind® sheets.

Possible solutions to paper jams on landscape FlexBind®

  1. Verify the sheet dimensions (length and width) exactly.
  2. Flip the stack in the feed drawer and run hinge trailing.
  3. Decrease the sheet length value by 0.02″ (0.5mm.)
  4. Adjust the “push” (sometimes called buckle) into the gripper in the perfector.  The setting is under Diagnostics/ Substrate/ Perfector and Conveyor tab.  Increasing the value will increase the depth the sheet is pushed into the gripper before printing the second side.
  5. Print to the proof tray rather than the stacker (if the stacker is having difficulty with the hinge.  Occasionally seen when printing hinge trailing out of the drawer.)


Printing through the gap – Gap Deletions

It is not recommended to print through the gap on any FlexBind® products.  However, most printers find they can achieve some degree of success printing through the gap on most products.  For tips on printing through the gap on portrait – grain long FlexBind® products, click HERE

The exception is the landscape FlexBind® format.  Regardless of the sheet weight, it has not been reliably demonstrated at any active user that ink can be completely transferred into the recessed gap.  It is theorized that the physical orientation of the gap against the blanket does not provide the intimate contact required to transfer ink properly into the gap.  Deletions occuring on white hinged products are more visible in a completed book.  For this reason, landscape FlexBind® products are only sold as either clear gap or black gap.   Click here for a picture of a Gap Deletion on a white hinged FlexBind product.

Printers that insist on printing through the gap for software (or other) reasons will find that an extra ink stripe will appear at the opposite end of the sheet.  The extra ink that did not completely transfer into the gap staying on the blanket causes this.  When the sheet is then duplex printed, that area on the blanket contacts the other end of the sheet (without the gap) and completely transfers all the ink to the paper.  While this is good news for cleaning the blanket and eliminating any blanket memory from the gap topography, it does not allow for offering a book image that would exceed the residue line.  Typically, this effect on an 18” (457 mm) long sheet would still allow for a 16.5” (419 mm) wide landscape book.

Printing landscape products on the HP Indigo 3500 and 5000.

Currently, all FlexBind® products are 13” (330 mm) wide by either 18 (457 mm) or 19” (483 mm) long.  Since the older HP Indigo presses cannot accept sheets wider than 12.6” (320 mm) the product cannot be certified to run.  Some printers have found ingenious ways to print the product anyway, all of which involve cutting down the sheet to 12.6”.  Some options are listed below.

  1. Using the Mazina(TM) FlexBind® branded product #94043, cut 0.2” (5 mm) off of each side.  There will still be paper gap stiffeners on each side that are 0.425” (11 mm) wide.  Run the product normally.
  2. On any landscape FlexBind® product, the printer can cut off one side on a guillotine cutter, removing the gap stiffener.  The product can then be simplex printed hinge-trailing through the press.