Extruder motor skipping

The main extruder stepper “clicks” or “tak-tak-taks” because it can’t deliver enough torque to push the screw. Almost always a tuning issue, not a hardware fault.

Symptoms

• A rhythmic “tak-tak-tak” sound from the main extruder motor
• The motor visibly jerks instead of rotating smoothly (look at the coupler between motor and screw)
• Extrusion is intermittent or stops entirely
• At low speed it seems fine, but as speed/acceleration increases it starts skipping

Possible causes

1. MVS (Max Volumetric Speed) too high for the current material/setup — the most common cause
2. Temperatures too low — material isn’t fully melted, screw can’t push it
3. No SmoothFlow with materials that need it (PETG, rPLA, reinforced grades)
4. Barrel clog — solid plug inside the extruder
5. Aggregated pellets from an overheated dryer

Diagnosis

Step 1 — Check the temperatures

Read the current setting on each of the three heating zones and compare:

• Start from the temperatures in the profile for your material. The temperatures for a material are whatever its Ginger Slicer profile says. The slicer is what sends them to the printer, so it is the only place they are true — see Material profiles, PLA or PETG.

If the values are below these starting points, raise them per the supplier datasheet and retest.

Note

Small nozzles want a cooler Feeding Zone. Slower flow means pellets sit longer at the inlet with less material passing through to cool it, so the top zone runs effectively hotter than the number suggests. The shipped PETG profiles already set Zone 1 well below the other two.

Step 2 — Check if SmoothFlow is in use

Ask: “Did you mix SmoothFlow into the pellets?”

• For PETG, rPLA, GF, or any reinforced grade → SmoothFlow is strongly recommended
• For virgin PLA at high MVS → SmoothFlow helps

Step 3 — Test extrusion at low speed

In Mainsail, manually extrude at low feed rate while the nozzle is at temperature:

• Material flows smoothly → it’s a flow / MVS / temp issue, not a clog
• Nothing comes out → possible clog → see Nozzle and barrel clog

Step 4 — Inspect the pellets

Open the hopper and check visually:

• Loose, individual pellets → ok
• Aggregated chunks (pellets stuck together) → the dryer ran too hot → break them apart and dry cooler next time; the material is not spoiled

Fix

Lower the MVS or raise the temperature

In Ginger Slicer, find the Max Volumetric Speed setting in the material profile. Reference values:

Material	Safe MVS
Each material	the MVS set in its own profile

If the motor skips at the current MVS, you can either:

• Lower MVS (most direct fix)
• Raise the temperature by 5–10°C (allows more flow without lowering speed)
• Add SmoothFlow (reduces friction, allows higher MVS without temperature increase)
• Combine the above

Add SmoothFlow

If it is not in use:

1. Dose at 0.05% to start (1 g per 2 kg of pellets)
2. Mix thoroughly in a sealed container
3. Load and purge until extrusion stabilizes
4. See SmoothFlow for full procedure

If barrel is clogged

See Nozzle and barrel clog for the purge procedure.

If pellets are aggregated

1. Empty the hopper
2. Break up the aggregated pellets, checking no compacted lump remains
3. Lower the dryer setpoint and dry a fresh batch — see Starting the dryer
4. Reload only loose pellets

How to prevent

• Always start with the recommended uniform temperature for the polymer; tune per grade
• Use SmoothFlow proactively with PETG, rPLA, GF, and recycled grades
• Back the dryer off as soon as pellets start packing together — that, not a fixed number, is the ceiling
• Visually inspect pellets each time before loading

Motor stops completely (no clicking sound)

Different from skipping: the motor stops entirely with no sound, instead of clicking rhythmically.

Cause: temperature too low — the material is not melted, so the screw cannot turn against it.

If raising the temperature does not restore movement, stop treating it as a material problem: a screw that will not turn points at the wiring, not the motor. Work through the four electrical checks — connector, loose connection, 55V step-up, driver. No E0 stepper has ever failed in the field.

Diagnosis:

• No extrusion, no “tak-tak” sound
• Motor feels unusually hot (stalled)
• Extrusion starts again after raising temperature

Fix: increase all zone temperatures to the polymer’s minimum recommended value, then retest. Raise in 5°C increments.

This is distinct from step-loss skipping: step-loss skipping means the motor IS turning but losing torque at peaks; complete stall means it can’t start rotating at all.

Motor temperature — what is normal

The motor that turns the extrusion screw is E0, the NEMA 34 on top of the gearbox. It runs hot under load, and customers regularly report that as a fault when it is not.

Reading	Meaning
Warm, up to 80°C on the body	Normal. The motor is working
Above 80°C	Not acceptable. Check the current setting on the DM860T DIP switches — not the Klipper config — and check for a partial clog creating back-pressure

E0 and E1 are different motors

E0 turns the extrusion screw. E1 is the mixing stepper on the hopper, which turns the auger — a smaller NEMA 23 at 45°. This section is about E0. See the two extruder steppers.

Notes

• The “tak-tak” sound is the audible signature of motor step loss — clear diagnostic clue
• Look at the screw coupler from the right side: jerky motion confirms step loss
• Motor jumping is a torque shortage, not a hardware fault — don’t replace the motor
• 80°C on the E0 body is the ceiling, not a target — above it, check the driver current setting

Related notes

• SmoothFlow
• Max Volumetric Speed
• Multi-Heating Zones
• Nozzle and barrel clog
• Main extruder motor

Sources

• Ginger Academy — Ginger Slicer / Max Volumetric Speed
• Ginger Academy — Liquid Masterbatch and SmoothFlow