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HP Indigo press series 5000 and HP Indigo press series 3000 Banding Troubleshooting Guide...
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HP Indigo Sheet-fed Presses HP Indigo press 3050, HP Indigo press 3500, HP Indigo press 5000 and HP Indigo press 5500 Troubleshooting Guide for Customer Engineers Banding...
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All other products or name brands are constitute publication or intent to publish, in trademarks of their respective holders. whole or in part. The HP Indigo press is a Class 1 Laser Part Number: Product containing high voltage power CA293-04200 supplies and laser light sources.
Contents Preface ........................... 4 General safety instructions........................4 About this troubleshooting guide......................4 Documentation conventions used in this guide .................. 4 Introduction ..........................5 What is banding ..........................5 Troubleshooting Methodology......................6 The banding troubleshooting overview ....................6 Banding troubleshooting road map ..................... 7 Banding troubleshooting ......................
• The guide assumes that the customer engineer has at least 6 months of experience on the HP Indigo presses. Documentation conventions used in this guide •...
Introduction What is banding • Banding appears as sets of lines across the width of Leading edge the page. 5 visible bands • Banding results from interference in the image production process at sensitive stages: • Image writing • Image generation •...
Troubleshooting Methodology Perform the following steps: 1. Perform all the steps in the “Pre-troubleshooting checklist” on page 8. 2. “Identifying the banding type” see page 9. 3. Perform all the steps in the relevant troubleshooting topic - “Troubleshooting by banding type” on page 10.
Banding troubleshooting road map High-level usage summary: • Define the banding type and work through the relevant troubleshooting checklist to resolve the issue. • For details on how to use this table see the “Troubleshooting Methodology” on page 6. For sample pictures see figures in “Appendix 1 Banding Types - Samples“ on page 15. Banding Troubleshooting Button Random...
TS_Grey20.jlt • TS_Banding2_Rev03.jlt These jobs can be copied from CD or downloaded from the HP Indigo documentation portal: http://h21021.www2.hp.com/C5/Test%20Jobs/default.aspx 2. Load the recommended paper: 100 - 150 gsm glossy paper, (minimum) size: 320 x 460 long grain. 3. Print a "base point" reference set of prints: TS_Banding2, TS_Gray20, TS_Registration 4 pix.
Troubleshooting by banding type Troubleshooting Repeatable banding with Non-mechanical causes • The banding cause is probably not mechanical: • This is because the TS_1on_3off vertical lines job is not sensitive to mechanical banding. • But sometimes the cause could still be mechanical, caused by pressure variations. For example BID pressure, 1 or 2 pressure.
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Troubleshooting Periodic banding Troubleshooting: 1. Classify the Band grouping: (Single or Group). 2. Mark as many continuous bands as you can on the print sample. 3. Measure banding periods in millimeters (mm). 4. Calculate the banding frequency (in mm or Hz) - see calculation below. 5.
Causes of Banding (C) Consumables banding There are four major causes: Press component Possible Causes Appearance / Banding type Burns, stains, short circuits, Usually appears like constant banding in some (C1) PIP foil mechanical damage and poor alternate separations (1 &...
Usually vibration banding 0.7—2.5 mm - constant (WH3) Writing head Faulty Writing head installation groups or periodic groups. (Especially on the HP on press interfaces. press interfaces Indigo press 3050.) General solutions for banding caused by the writing head 1.
4. Parts that vibrate under specific loads that may interfere with the writing head. - For example on the HP Indigo press 3050 - stop finger noise during paper feed. (M2) Gear transmission issues interfering with dot placement Gear transmission issues in the drums and gears, during image writing and transfer, interferes with dot placement.
Appendix 2 Gear Transmission Schemas These schemas are used to locate a gear, when you know the number of teeth in the gear. How to use these schemas: 1. Identity the gear using the “Appendix 3 Periodic banding table – caused by gears and rotating parts”...
Appendix 3 Periodic banding table – caused by gears and rotating parts This table is used to identity a gear or pulley / other component, when you know the frequency of the banding or misregistration. How to use this table: 1.
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Gear/Pulley Gear/Pulley Banding Banding Gear or Pulley / No. of Gear type / Press type Frequency Frequency Other component teeth Sub-assembly [mm] [Hz] 50.8 Main motor Drive 5000 Main motor + controller Drive 5000 33.5 36.4 Rotor A pulley Paper feed 3050 32.7 37.2...
Appendix 4 Constant banding table Diagnostic table for constant banding caused by local loads and other causes. Distance from LE Local loads Gripper Press Sepr. shaft Occurs Diagnostic tips action action Print a single proof for diagnostic. 31-39 65-70 Opening Sheet exit transfer Related to stop stations, gripper shaft,...
Appendix 5 Troubleshooting constant banding caused by gear teeth • A defective or dirty tooth on one of main gears causes constant banding. • You will probably not find them it in the Constant banding table. • Constant banding - Some separations A defective tooth on the PIP gear usually causes banding on the some separations.
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Steps 1. Use one of the banding diagnostic jobs. Mark the banding on your print sample. 2. Read the position of the banding on the printed scale from the leading edge of page, in degrees. 3. For example: you have banding at 240 deg. 4.
Run the press. Perform fine tuning according to the Balancing the second transfer pressure with SPV document (CA293-04790). Note: For HP Indigo press 5000 with HP Indigo press software version 7.4.3 and higher - The SPV software tool can be used for adjusting 2 transfer pressure tuning.
If a "TS_1on_3off vertical line transparent diagnostic foil" is available, you can check if banding is mechanical by doing the following: Note: You can create this foil for yourself by running the TS_1on_3off vertical line transparent diagnostic foil job on transparent substrate. You can download the job from the HP Indigo documentation portal: http://h21021.www2.hp.com/C5/Test%20Jobs/default.aspx 1.