How to Store and Dry 3D Printing Filament

Moisture is the silent killer of print quality. Learn how to store filament properly, recognize wet filament, and dry it back to perfect condition — with drying temperatures and times for every material.

If your prints have become suddenly rough, stringy, or full of bubbles — and you haven't changed any settings — wet filament is the most likely culprit. Most printing problems that people spend hours troubleshooting are simply caused by moisture-contaminated filament.


Why Moisture Destroys Print Quality

Most 3D printing filaments are hygroscopic — they absorb moisture from the air. When wet filament is heated in the nozzle, that moisture instantly vaporizes into steam. The result is:

  • Popping, crackling, or hissing sounds from the nozzle
  • Rough, bubbly surface texture (tiny craters from steam escaping)
  • Excessive stringing
  • Inconsistent extrusion and weak layer adhesion

Which Materials Are Most Affected?

MaterialMoisture SensitivityNotes
Nylon (PA)ExtremeCan absorb 3%+ of its weight in hours
PVAExtremeAbsorbs so fast it becomes unusable
PCVery HighMust be dried before every use
ABSHighOften mistaken for temp issues
ASAHighSame as ABS
PETGModerate-HighVery common source of stringing
TPUModerateStrings excessively when wet
PLALow-ModerateTakes longer to absorb

How to Recognize Wet Filament

During printing:

  • Popping, crackling, or hissing from the nozzle
  • Steam or wisps of vapor from the nozzle
  • Extrusion that looks foamy or rough

On finished prints:

  • Rough, pitted, or bubbly surface texture
  • Stringing much worse than usual
  • Transparent filament appears yellowed or cloudy

On the spool:

  • Nylon that snaps when bent (dry Nylon is flexible — wet Nylon is brittle)

How to Dry Filament

Recommended Temperatures and Times

MaterialTemperatureTime
PLA45–50°C4–6 hours
PLA+50–55°C4–6 hours
PETG65–70°C4–6 hours
ABS65–80°C4–6 hours
ASA65–80°C4–6 hours
TPU (95A)50–55°C4–6 hours
Nylon (PA6)80°C8–12 hours
Nylon (PA12)70°C6–8 hours
PC80–90°C8–12 hours

Do not exceed the glass transition temperature of the filament — PLA is the most sensitive, keep it at 45–50°C maximum.

Drying Methods

Dedicated filament dryer (recommended): Products like the Sunlu Filadryer S2 or eSUN eBOX have accurate temperature controls. Cost: $30–80.

Food dehydrator: An excellent cheap option with accurate temperature control for most materials.

Kitchen oven: Works in a pinch but most ovens are inaccurate at low temps. Use an oven thermometer.


How to Store Filament

Vacuum bags with desiccant: The cheapest and most effective storage. One 50g silica gel packet per spool. Recharge desiccant in the oven at 120°C for 2–3 hours.

Airtight containers: Storage totes with gasket lids (like Sistema or Iris boxes) work well for multiple spools.

Dedicated dry boxes: Products like the eSUN eBOX or Sunlu Filadryer let you store and print from a sealed heated environment — the best solution for Nylon and PC.

Priority for dry storage:

  1. Nylon, PVA, PC — store immediately in dry box or vacuum bag
  2. PETG, ABS, ASA, TPU — seal with desiccant between uses
  3. PLA — seal when storing long-term

Quick Checklist

  • Store all filament in sealed containers with desiccant when not in use
  • Dry Nylon, PC, and ABS before every use if stored open
  • Listen for popping/crackling — that's your early warning sign
  • Recharge desiccant packets before they saturate

See our Settings database for material-specific drying recommendations alongside print profiles.