HP Designjet 3D Service Manual page 129

5. Excess Material Inside Head
- Filament Buckled / Spaghetti
Head
- Encased Head
6. Filament motor is running very
fast.
1. Check for loose heater block clamp screws.
2. Make sure the head connectors are seated
properly.
3. Check air plenum for: proper hose
connection; properly seating; cracks or
damage.
4. Check to make sure head blower fan hose
is connected to blower.
5. If extrusion fails on first layer with a used
modeling base, retry with a new one
6. Rerun Z calibration
7. Plugged Liquefier - replace tips.
8. Inspect model for excessive overfill.
a. Toolpaths should not overlap by more
than 50%. If so, reorient and
reprocess STL.
b. If model curl has caused the part to
contact the tip, reprocess part with less
dense fill. Re-run tip Z cal if part is
separating from supports
c. If part curl continues, see part curl
section
9. Check idler wheel gap.
10. Check liquefier alignment.
1 1. Head idler spring is deformed or installed
improperly. Replace head idler spring.
12. Possible head temperature issue
a. Replace head board and TC Amp
board.
b. Replace toggle head assembly.
13. Head motor power wires or encoder
failure - replace toggle head
14. Blower fan not supplying enough air flow -
weak or stalling. Replace fan.
15. Replace umbilical cable
16. Replace controller board
17. In case of Z shift:
a. Realign Z guide rods.
b. Replace Z motor and leadscrew.
c. Replace Z assembly.
1. Make sure the head connectors are seated
properly.
2. Bad motor. Replace toggle head assembly.
3. Broken wire in the umbilical cable. Replace
umbilical cable.
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