If one or both sides of the FieldPrinter stop depositing ink, either immediately or after printing for a short time, work through the steps below in order before initiating a swap.

Symptoms

• Printer deposits ink briefly, then stops
• One or both sides produce no marks on the surface
• Issue persists across multiple cartridge swaps

Step 1: Verify Ink Type Selection on the iPad

Before touching hardware, confirm the app is set to the correct ink type (solvent vs. water-based). A mismatch can prevent ink flow even with good cartridges. Correct this in the Dusty app before proceeding.

Step 2: Power Cycle the Robot

A full power cycle can reset the print head state and clear transient faults.

1. Turn the robot off.
2. Remove the battery.
3. Wait 15 seconds.
4. Reinsert the battery and power the robot back on.
5. Test printing before proceeding to further steps.
    

Step 3: Flick and Prep the Cartridge Correctly

Important: Shaking cartridges vigorously introduces air bubbles and can make the problem worse. Use a firm wrist-flick; not a full shake.

1. Remove the cartridge.
2. Give it a single firm flick (like shaking down a thermometer).
3. Confirm ink is flowing from the nozzle tip; you should see a small bead of ink.
4. Wipe the nozzle clean before reinserting.
    

Step 4: Clean the Print Head Pins and Nozzles

1. Flip the robot so the print heads face down.
2. Using a lint-free wipe, push firmly into the ink nozzles while the print head faces the ground. This helps dislodge any dried ink or debris blocking the nozzle.
3. Inspect the electrical pins on both the cartridge and the print head cradle; clean any ink residue with the wipe.
4. Reinsert the cartridge and test.
    

Step 5: Remove the Wind Guards

Wind guards can restrict ink flow in certain conditions. Remove them and test printing without them. If ink flow improves, the wind guards may need cleaning or replacement.
 

Step 6: Force Ink Using the Controller

Use the joystick to manually force ink through the print head:

1. Drive the robot forward.
2. While driving, hold down the left trigger, the right trigger, or both.
3. Repeat several times; it can take multiple attempts before ink starts flowing consistently.
4. Once one side begins depositing ink, isolate that side and print the same object several times in a row to keep it flowing.
    

Step 7: Check the Print Head Cable

Inspect the cable connecting the print head to the robot body:

• Look for visible kinks, cuts, or abrasion along the cable length
• A damaged cable can cause intermittent ink dropouts
   

Step 8: Try Fresh Cartridges

If none of the above resolves the issue:

• Swap in unused cartridges from a different batch if available
• The issue may be a bad batch — note the cartridge batch if you proceed to a swap so engineering can follow up