i2 Printhead Alignment

Optimal print quality requires that the printheads be properly aligned. Printhead alignment is done during the initial setup process and may be done as a maintenance task at other times if needed.

Preliminary Checks

The following steps should be taken before changing the printhead alignment. Modifying the alignment without first completing these checks may result in misaligning the printheads while unintentionally compensating for a mechanical issue.

  • Ensure that the printer is level, adjusting the height of the table’s four feet/casters as needed.
  • Ensure that the distance between the top of the platen and the bottom of the printhead mounting bracket is the same at each of the platen’s four height adjustment screws.
  • Clean the encoder strip.
  • Clean and lubricate the carriage rails.

Alignment Process Overview

The Head Adjustment tab of the i2 UI program’s Maintenance screen is where adjustments are made, in response to visual feedback from test pattern prints.

  1. The Mechanical Offset is adjusted first to position the starting x,y position (0,0 by default) at the flat front-right corner of the platen — inside the beveled edge.
  2. Forward, Reverse, and Bi-directional (horizontal) alignment must be done at the 1200 DPI setting.
  3. Vertical alignment between the two heads is done using the White-Color Distance control.
i2 alignment types with numbered callouts.

Let’s get started!

Mechanical Offset

The Mechanical Offset‘s ‘Table X’ and ‘Table Y’ settings calibrate the top-left corner of print jobs, which may also be thought of as the near right corner of the platen when viewing from the front of the printer.

Mechanical Offset's target position

i2 platens have an approximately 1/8″ bevel around their outside edge. This should not be considered part of the platen’s printable area. We want to confirm that a nozzle check print has its top-left corner (bottom-right from the front of the printer perspective) at the edge of the flat area of the platen. There should be virtually no space between the platen’s flat edges and the ink, and there should be no ink on the beveled part of the platen.

  1. Select the i2_Nozzle_Chart_Preview.bmp file from the Test path in the i2 UI software’s Job Setting section.
  2. Set both the Top & Left Margins of the Job Setting section to ‘0’.
  3. Send the job to the print queue and print it.
Mechanical Offset calibration Job Setting

If the top-left corner of the nozzle check pattern print isn’t positioned at the corner of the platen (the flat part of the platen, not on the beveled edge) then we’ll need to change the X value (for horizontal adjustments) and/or the Y value (for vertical adjustments).

Increasing the values shifts the print toward the center of the platen. Decreasing the values shifts the print towards the edges of the platen.

If adjustments are needed, click the Save button after changing any values and before running another test print. Repeat as needed to position the corner of the print at the corner of the platen.

Horizontal Alignment

There are three horizontal alignments: Forward, Reverse, and Bi-Directional. These names describe carriage movement when printing occurs — when the carriage is moving in the forward direction only, in the reverse direction only, or in both directions. Most printing is done bi-directionally for the speed benefit, but alignments for all three types of printing must be performed.

Carriage Forward movement as defined as right-to-left when facing the front of the printer, which is left-to-right from the perspective of the printed image.

The process for checking and adjusting the Forward & Reverse alignments are identical so we’ll provide step-by-step details for the Forward alignment, and only list the differences for the Reverse alignment.

Forward horizontal alignment

  1. Select the ‘X-1200 DPI’ setting at the bottom of the Forward section on the Head Adjustment tab of the i2 UI software’s Maintenance screen.
  1. Set Direction to ‘Uni F’ and select the i2_P_Offset_1200_Uni_F_Preview.bmp test file in the Job Setting section of the i2 UI software. The image can be positioned as desired to use available space on a DTF sheet or other transparent plastic sheet.
  1. Print the test image.
  2. Analyze the test print to determine if adjustments are needed, focusing on the highlighted area in the image below.
i2 Forward Alignment Print Sample
  • First analyze the four white channels, W1, W2, W3, and W4.
i2 Alignment - Forward Whites
  1. Each section (W1, W2, W3, and W4) has a series of numbers going from -5 to +5. Above each number are black & white vertical line segments. For each of these ‘W’ groups, identify which black & white pair form a single straight vertical line, or which is closest to a straight vertical line if none are perfectly aligned, and note the corresponding number of each.

    In the pictured example, we would note the following:
    W1: +3
    W2: 0
    W3: +1
    W4: +1
  2. The next step is to sum (or add) the noted numbers to the values currently appearing in Row2 of the Forward Head Adjustment section. The image at the top of this section shows that the Row2 values in the Forward section for W1, W2, W3, and W4 are all ‘0’, so we have the easiest possible math of simply adding the noted numbers to 0.
  3. After updating the values, click the Save button at the bottom of the Maintenance screen.
  4. Loop through steps 3 through 7 until the black & white line segments for W1, W2, W3, and W4 each form straight vertical lines in the 0 (zero) position.
  5. Once the whites are all aligned, find the number associated with the best-aligned vertical line pairs for Cyan, Magenta, and Yellow and sum them with numbers currently in the C, M, and Y rows of Row2.
i2 CMY horizontal alignment
  • The CMY channels in the above example already have the vertical lines perfectly aligned in the 0 (zero) position.

Reverse horizontal alignment

The process for the Reverse alignment is identical to the Forward alignment with the following exceptions.

  • Select the ‘X-1200 DPI’ setting at the bottom of the Reverse section on the Head Adjustment tab.
  • Select i2_P_Offset_1200_Uni_R_Preview.bmp in Job Setting.
  • Set Direction to ‘Uni R’.
  • When updating values based on analysis of the test print, sum with the current numbers in Row1 in the Reverse section of the Head Adjustment tab.
If values are updated we must click the Save button at the bottom of the Maintenance screen before continuing.

Bi-Directional horizontal alignment

Once the Forward and Reverse alignments are completed, we want to make sure the horizontal alignment is also good when printing in the Bi-directional mode.

Start by clicking the X-1200 DPI option in the Bi Direction box.

Bi Direction - X-1200 DPI

Bi-directional alignment teseting can be done using either of the 1200 Uni offset test patterns: i2_P_Offset_1200_Uni_R_Preview.bmp or i2_P_Offset_1200_Uni_F_Preview.bmp.

Likewise, the Direction option in Job Setting can be set to either Bi F or Bi R.

Bi-di alignment Jo Setting setup

After printing a test pattern, analyze the eight columns of stacked squares (one for each color channel), where each square is divided into four smaller squares.

Alignment columns

In the above example, we can see that the bi-directional alignment is good because the upper pair of boxes in each column is aligned with the lower pair of boxes.

In the below example, the bi-directional alignment must be adjusted to make the upper and lower pairs of boxes line up with each other.

Bi-Di over 3 on Bi-R or under 3 on Bi-F

The position of the lower pair of boxes in each column is offset to the left of the upper pair of boxes (as well as the rest of the test pattern) by approximately 3mm. So to correct the alignment we will need to adjust the Bi Direction value by 3mm.

Bi Direction alignment offset

In this example, the Bi Direction value was set to zero (“0”) but you may find another number on your installation. To adjust the alignment we’ll want to change the value by either adding (+3) or subtracting (-3) to the current of zero.

Here’s how to know if you need to enter ‘3’ or ‘-3’ (the ‘+’ sign is not used).

If the above example was printed using the Bi F direction setting then we would enter ‘-3’, or if printed using the Bi R direction setting we would enter ‘3’.

Don’t worry too much about remembering which offset direction calls for entering a larger or smaller number. You can always change directions (upward or downward) if your entry made the offset worse. You can also use decimal fractions (2.7, for example) to fine-tune the alignment.

Remember to Save after each change before printing the next test patter.

White-Color Distance (Vertical Alignment)

Vertical alignment of the two printheads is done using the White-Color Distance setting. As the software’s label describes, performing a vertical alignment is essentially calibrating the vertical position of the two printed ink layers as laid down by the separate white and color (CYMK) printheads.

Rather than using numbered line segments in a test pattern, as in the horizontal dimension, we simply evaluate any test pattern or design print. The adjustment is made by entering the number (in millimeters) by which the layers are out of alignment.

For example, let’s say the white layer is printing 3 mm above the color layer (as prints are oriented on the platen with the top of the design toward the front of the printer). To adjust the alignment we would enter “-3” in the White-Color Distance text box, then click the Save button.

White-Color Distance (-3)

After making an adjustment we always run another test print to see if we nailed it or if we need to make another adjustment.

You can have very high confidence that you will get excellent accuracy and detail when printing even the most challenging designs with all of the alignment options optimized!

Ethernet Configuration for i2

The OmniPrint i2 printer uses the TCP/IP (Transmission Control Protocol/Internet Protocol) over an Ethernet connection to communicate with your PC, along with USB 3.0. The Ethernet connection requires a one-time configuration in Windows, which OmniPrint Training sets up for you during your initial training session.

The following information will help you to perform that same configuration if you should ever need to update your PC’s Ethernet adapter or if you’ve installed the i2 UI and Print Pro software onto a new PC.

Your OmniDTF printer and its software implementation are not designed to communicate over the Internet or any other network. We use a simple point-to-point connection between one PC and the printer, directly connected with a single Ethernet (“RJ45”) cable.

We configure TCP/IP parameters in the Control Panel of Microsoft Windows.

IP Address Configuration

Windows Control Panel’s Network and Sharing Center is where any Ethernet adapters to be used in a Windows PC are configured. Use the steps demonstrated in the video below or the following step-by-step instructions to configure an Ethernet adapter for use with the i2.

Video demonstration


Step-by-step instructions

  1. Run Windows Control Panel.
  2. Click on Network and Sharing Center.
Windows Control Panel - Network and Sharing Center
If you don’t see Network and Sharing Center in Windows Control Panel, it is because Control Panel is in the Category View mode. In that case, first click on Network and Internet, then click on Network and Sharing Center.
  1. Select Change adapter settings
Change adapter settings
  1. Double-click on the Ethernet adapter to be used (or right-click on the adapter and select Properties).
Control Panel - Network Adapters
Your Ethernet adapter may have a different description than the Ethernet 4 pictured above. Don’t be concerned if there is a red ‘x’ on the adapter, which simply means that it isn’t currently connected to anything.
The ExpressVPN TAP Adapter does not represent a physical (actual) Ethernet hardware port and is not usable. This is strictly a “virtual” adapter built into Windows for creating VPN connections and has no purpose for the OmniDTF.
  1. Double-click on Internet Protocol Version 4 (TCP/IPv4) (or single-click on it and then click the Properties button).
Ethernet Properties
  1. Click the Use the following IP address radio-button (if it isn’t already selected) and enter the following, then click ‘OK‘.
    IP address: 192.168.100.1
    Subnet mask: 255.255.255.0
i2 Ethernet IP properties

The Ethernet configuration is now complete!

i2 Periodic Maintenance

Stay on top of these few, easy maintenance tasks to keep your OmniPrint i2 reliably printing at maximum quality.

Clean the carriage encoder strip

  1. Release the printhead carriage from its Home position using the C Out (carriage out) button on the the Motion & Sensors tab of the i2 UI program.
    i2 Carriage Out
  2. Clean the exposed section of the encoder strip with a lint-free cloth wetted with 70% isopropyl alcohol.
    i2 carriage encoder strip
    • Manually reposition the carriage further to the left then clean the section of the encoder strip previously blocked by the carriage.
  3. Return the carriage to its Home position using the C In (carriage in) button on the Motion & Sensors tab of the i2 UI program.
    i2 UI C In (carriage in) button

Clean & Lube the Carriage Rails

  1. Release the printhead carriage from its Home position using the C Out (carriage out) button on the the Motion & Sensors tab of the i2 UI program.
    i2 Carriage Out
  2. Wipe the exposed section of the front & rear carriage rails (outlined in red below) with a clean, dry, lint-free cloth.
    i2 carriage rails
    • Reposition the printhead carriage further to the left to expose the section of the carriage rails previously behind it and clean that section.
  3. Apply dabs of blue grease to the top, bottom, and face of the front & rear rails, then move the carriage back and forth to distribute the grease across the full width of the rails.
  4. Clean off any excess grease, then return the printhead carriage to its Home position using the C In (carriage in) button on the Motion & Sensors tab of the i2 UI program.
    i2 UI C In (carriage in) button

Clean the Spit Trays

Clean any excess ink from the spit trays and replace the soak pads, as needed.
i2 Spit tray, right

OmniPrint i2 Daily Shutdown

Properly shutting down your OmniPrint i2 printer at the end of a production day is the most critical maintenance task.

This shutdown maintenance supports producing high-quality prints and maximizing economical operation. That’s because everything we do during the shutdown routine is focused on protecting and prolonging the service life of the printheads.

Process Summary

  1. Run a head cleaning.
  2. Close the ink clips.
  3. Clean the wiper blades.
  4. Clean the capping station seals.
  5. Clean the printheads’ undercarriage.
  6. Flush ink residue from the capping stations.
  7. Wet cap the printheads.
  8. Clean up any ink under the capping stations.
  9. Exit the i2 UI program.
  10. Turn of the i2 printer’s power.
  11. Empty the waste ink bottle.

Illustrated Step-by-Step Details

  1. Run a head cleaning by clicking the Cleaning button on either the Motion & Sensors or Maintenance screen.
    i2 head cleaning from Motion & Sensors or Maintenance screens.
  2. Close the ink clips
    i2 clips closed
  3. Clean the wiper blades with an anti-static foam swab or microfiber cloth wetted with Super Cleaner.
    i2 wiper blade cleaning
  4. Clean the capping stations seals using an anti-static foam swab or microfiber cloth wetted with Super Cleaner.
    i2 capping station seal cleaning
  5. Clean any ink on the underside of the printheads mounting bracket and the side edges of the printheads, being careful to avoid contacting the mirror-like nozzle plates of the printheads (highlighted with a red tint below).
    i2 undercarriage
  6. Flush ink residue from the capping stations.
    • Fill the capping stations with Super Cleaner.
      Both capping stations with Super Cleaner.
    • Run Suction to flush the Super Cleaner and any ink residue out the capping stations.
      Motion & Sensors - Motion box - Suction 5-sec
    • Repeat (or continually squirt Super Cleaner into the capping stations while Suction is running) until the loose ink is rinsed out.
  7. Wet cap the printheads.
    • Fill both capping stations with Super Cleaner until you can see the surface tension of the liquid sitting slightly above the top of the rubber capping station seals.
      Both capping stations full of Super Cleaner demonstrating surface tension dome.
    • Click the Home icon on the Motion & Sensors screen to send the carriage to its Home position, completing the wet cap process.
      i2 UI Home button
  8. Clean up any liquid (ink or Super Cleaner) that may have spilled out of the capping station while flushing and wet capping.
    • Remove the right side access panel for access and visibility.

  9. Exit the i2 UI program by clicking on the door icon in the upper-right corner of its window.
    i2 UI Exit icon.
  10. Switch off the i2 printer’s power.
    i2 power switch highlight
  11. Empty the waste ink bottle.
    i2 waste ink bottle, empty

OmniPrint i2 Daily Startup

Follow this procedure to ensure that your first print of the day, and every print, is the high quality you expect from your OmniPrint i2.

Following a summary of the steps, we’ll provide the step-by-step details.

Daily startup summary

  1. Turn on the i2 printer’s power switch.
  2. Check the level in your ink bottles and top them off, as needed.
  3. Confirm that the white ink is well-mixed, with no separation of the pigment from the base.
  4. Check the waste ink bottle’s fluid level and empty, as needed.
  5. Run the i2 UI program on the printer’s PC, after waiting at least 20 seconds from the time the printer’s power was switched on to ensure that it’s ready to communicate.
  6. Circulate the white ink for at least 3-minutes, then toggle the Circulation switch to the OFF (red) position.
  7. Open & reposition all 8 of the ink clips.
    • If the printer has been idle a few days, you may want to first open only the white clips to prime the white ink from the manifold through the dampers. Then open all ink clips.
  8. Run a head cleaning for 3-5 seconds.
  9. Run Autoscan to set the platen height.
  10. Print a nozzle check

Daily startup details

Power on and preliminary checks

Turn on the rear power switch, then proceed through some preliminary checks before loading the i2 UI software on the printer’s PC. We do this to allow the printer’s electronics at least 20-seconds to become fully functional before the PC and i2 UI software establish a connection with the printer.
Power up

After turning on the printer’s power switch we do the following preliminary checks:

  • Confirm that all ink levels are at least near the top of the vertical slot in the back of the bracket that holds them. Refill as needed, keeping the ink level below the fittings where the ink tubes enter the bottle. We want the ink levels maintained between the two red lines in the below image.
    Ink bottles; fill & full levels.
  • Make sure the white ink’s pigment hasn’t separated from its base in the ink bottle. The white ink bottle should be lifted out of its bracket a shaken side-to-side enough to ensure that it is well-mixed daily. Do this first because you’ll then need to let the white ink settle for 20 minutes or so to ensure that any bubbles introduced while shaking it have risen to the top and dissipated, to avoid getting air into the ink line.
  • Empty the waste ink bottle if it isnt already near empty.
    waste ink bottle
i2 UI load and printing prep
  • Load the i2 UI program on the printer’s PC. Several startup tests will run, and the printer will sound its initialization fanfare when completed.
    i2 UI initialization
    The printer is now ready for use.
  • Circulate the white ink for 3 minutes or longer.
    i2 UI white ink circulation settings and control.

    After the 3-minutes of circulation is completed, click on the Circulation switch to turn circulation to the OFF (red) position.
    Circulation switch OFF.
The Circulation switch in the i2 UI software must be switched to the OFF (red) position before opening the white ink clips, and must remain OFF whenever the white ink clips are open.
  • Confirm that the white ink in the tubes between the manifold and the white dampers is well-mixed, with no separation of the pigment from the base.
    • If the ink in those short tubes is not fully opaque (a solid white) then we’ll want to “prime” the white ink briefly. If this is needed, open just the white ink clips then turn on Suction for 5 seconds.
      Prime with Suction for 5 seconds.
  • Open all 8 of the ink clips, then run a 3-5 second head cleaning.
    i2 UI head cleanings
Print a nozzle check
  • Place a transparent sheet of plastic, such as a sheet of DTF film, onto the platen. Put it at the front edge of the platen, horizontally centered.
  • Run Autoscan to set the platen height.
    Autoscan button on Motion & Sensors tab
  • Load the nozzle check image in the Job Setting section of the i2 UI app.
    Job Setting for nozzle check print
    • Select the Test file path by clicking the page & magifying glass icon in the top-left corner of the Job Setting section.
    • Select the i2_Nozzle_Chart_Preview.bmp file from the file list.
    • Position the image in the desired position on the virtual platen using the Top Margin and Left Margin buttons (usually a 0.25 inch top margin and at the left margin default of centered).
    • Use defaults of Direction = “Bi F” and Mode = “All” for printing nozzle checks
      Job Setting - annotated Mode & Direction
  • Click the red ‘+’ button in the Job Setting section to send the configured nozzle check print job to the print queue.
    Send nozzle check from Job Setting to the Print Status print queue
  • Click the filename in the print queue (above) on the Print Status section.
    • The test image will appear under in the graphic under the Table heading.
  • Click the blue right-arrow (“play”) button to send the nozzle check to the printer.
    Print Status - nozzle check loaded (v1.9.0)
  • After the i2 beeps, press its flashing blue Start button to run the print.
    i2 printer Start button
    • The nozzle check test pattern prints.
  • If the nozzle check pattern is 90% or better, you’re ready to start your production day.
    i2 nozzle check print
    • Run additional iterations of head cleanings & nozzle check prints, as needed, to achieve 90% or better in each color channel.