All guidesClogging / no extrusion

How to Fix a Clogged 3D Printer Nozzle

Extrusion stops or slows dramatically mid-print, often with an audible clicking sound as the extruder gear grinds against filament that isn't moving.

Common causes

  • Debris or burnt residue in the nozzle

    Built-up carbonized filament from past prints can partially or fully block the nozzle's opening.

  • Heat creep

    If the heat break and heatsink aren't cooling properly, filament can soften too early and jam higher up in the hot end, above the nozzle.

  • Filament grinding instead of feeding

    If the extruder gear can't grip the filament — often from too much retraction or a jam downstream — it carves a groove into the filament instead of pushing it.

  • Moisture in the filament

    Absorbed humidity can flash to steam inside the hot end, disrupting consistent flow and contributing to clogs.

How to fix it

  • Perform a cold pull

    Heat the nozzle, then let it cool partway before pulling the filament back out — this is the standard, reliable way to clear internal debris.

  • Check your heat break cooling fan

    Make sure it's spinning and unobstructed — this is the most common cause of heat creep jams.

  • Reduce retraction distance/speed

    If grinding correlates with retraction moves, dialing these back can stop the extruder from chewing through the filament.

  • Dry your filament

    Especially for PETG, nylon, or TPU that's been sitting exposed to humidity.

  • Replace the nozzle if needed

    Abrasive filaments like carbon-fiber or wood-filled blends wear out brass nozzles — a worn or damaged nozzle may need replacing outright.

Still stuck?

ForgePrint diagnoses the exact cause for your printer and filament — describe it, or just upload a photo.

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