Guide

How to Dry 3D-Printing Filament Correctly

Most filaments are mildly hygroscopic; PETG, nylon, and TPU are very much so. A spool left out for a week in humid weather is often the real reason behind sudden stringing or a sandy surface texture.

Step-by-Step

  1. Diagnose the symptoms

    Listen for a faint popping or crackle at the nozzle, and look for excessive stringing, blobs, or a rough surface. Those are usually moisture, not a slicer setting.

  2. Choose a temperature

    PLA: 45 °C. PETG: 65 °C. ABS/ASA: 70 °C. Nylon: 80 °C. TPU: 50 °C. Stay 10–15 °C below the glass-transition temperature of the polymer.

  3. Dry for long enough

    Run for 6 hours minimum for PLA/PETG, 8–12 hours for ABS/ASA/TPU, and 12–16 hours for nylon. Severely wet nylon can need 24 hours.

  4. Print directly from the dryer

    Re-absorption begins immediately once a dry spool returns to room air. Print straight from the dryer, or transfer to a sealed dry-box with fresh desiccant.

  5. Store properly afterwards

    Resealable bags with silica gel work for short term; a sealed dry-box (filament fed through a PTFE tube) is best for long term.