{
  "opening": "On the thread that is about a pop, the leading comments say the spool is wet and the steam leaves a gap. One of the five links is about cameras. Drying temperatures stay on the drying page.",
  "question": "Why does filament bubble or pop while printing?",
  "slug": "bubbles",
  "useCase": "drying",
  "useCaseLabel": "Drying",
  "updated": "2026-10-21",
  "shortAnswer": "On the thread that is about a pop, the leading comments say the spool is wet and the steam leaves a gap. One of the five links is about cameras. Drying temperatures stay on the drying page.",
  "recommendedMaterials": [
    "pla",
    "petg"
  ],
  "printerConsiderations": [
    "A pop followed by a hole is the moisture sign on r/FixMyPrint. The same thread is already written up on the wet-filament page.",
    "r/prusa3d is ESP32 cameras. The top comments are about cameras, not steam.",
    "Do not copy one brand's drying hours onto a row that lists different hours."
  ],
  "pros": [
    "The two moisture comments are quoted as supplied, including the cut-off ending.",
    "Drying setpoints are not repeated from the drying guide."
  ],
  "cons": [
    "The highest-scored thread in the URL list is not about filament bubbles."
  ],
  "community": "r/FixMyPrint 1098exl, score 80: \"Popping sounds are a clear sign of filament that has absorbed moisture. The popping sound is the water literally boiling and exploding out as vapor as it hits the extremely hot nozzle. This explosion of vapor blows the surrounding filament away creating holes or pockets where it happens. Just need t…\". Score 21: \"A popping sound really indicates wet filament. The water evaporates in the nozzle, the steam has a bigger volume than the liquid water, and by that you get a gap in your print.\" r/prusa3d 1ma37n9, score 20, is about cheap cameras, one per printer. Score 8 says the first camera overheats even with a heatsink. The editorial summary says bubbles or popping almost always mean wet filament. That matches the FixMyPrint excerpts and not the camera thread. No excerpt was supplied for r/prusa3d 1mndze5, r/FixMyPrint 11k1puf, or r/FixMyPrint 1jtph19.",
  "related": [
    "hygro",
    "drying",
    "storage",
    "petg_stringing"
  ],
  "faq": [
    {
      "q": "Why does filament bubble or pop while printing?",
      "a": "On the thread that is about a pop, the leading comments say the spool is wet and the steam leaves a gap. One of the five links is about cameras. Drying temperatures stay on the drying page."
    },
    {
      "q": "Is every pop wet filament?",
      "a": "The score-80 and score-21 comments on r/FixMyPrint say a pop is water boiling in the nozzle. The wet-filament page also records a comment on that same thread where a pop was an air gap after a hotend rebuild. Read that page before treating every click as moisture."
    },
    {
      "q": "Where are the drying temperatures?",
      "a": "On the drying guide and in the filament drying dataset. SUNLU PLA's 200 °C (392 °F) and 60 °C (140 °F) print from the pop thread sits inside 190–230 °C (374–446 °F) and 50–70 °C (122–158 °F)."
    }
  ],
  "sources": [
    {
      "title": "SUNLU filament wiki",
      "url": "https://www.sunlu.com/wiki/61",
      "kind": "manufacturer"
    },
    {
      "title": "SUNLU PETG product page",
      "url": "https://www.sunlu.com/products/petg-3d-printing-filament",
      "kind": "manufacturer"
    },
    {
      "title": "Polymaker US PolyLite PLA product page",
      "url": "https://us.polymaker.com/products/polylite-pla",
      "kind": "manufacturer"
    },
    {
      "title": "Bambu Lab PETG HF technical data sheet",
      "url": "https://store.bblcdn.com/ce12d65176a94f1086e6aefa238e62e2.pdf",
      "kind": "datasheet"
    },
    {
      "title": "Community source, r/prusa3d 1ma37n9",
      "url": "https://www.reddit.com/r/prusa3d/comments/1ma37n9/",
      "kind": "reddit"
    },
    {
      "title": "Community source, r/FixMyPrint 1098exl",
      "url": "https://www.reddit.com/r/FixMyPrint/comments/1098exl/",
      "kind": "reddit"
    },
    {
      "title": "Community source, r/prusa3d 1mndze5",
      "url": "https://www.reddit.com/r/prusa3d/comments/1mndze5/",
      "kind": "reddit"
    },
    {
      "title": "Community source, r/FixMyPrint 11k1puf",
      "url": "https://www.reddit.com/r/FixMyPrint/comments/11k1puf/",
      "kind": "reddit"
    },
    {
      "title": "Community source, r/FixMyPrint 1jtph19",
      "url": "https://www.reddit.com/r/FixMyPrint/comments/1jtph19/",
      "kind": "reddit"
    }
  ],
  "recommendations": [
    {
      "rank": 1,
      "note": "SUNLU PLA lists 190–230 °C (374–446 °F) and a bed of 50–70 °C (122–158 °F). The pop thread printed PLA at 200 °C (392 °F) and a 60 °C (140 °F) bed, inside this row. Drying for this spool is on the drying guide, not restated here.",
      "brand": "SUNLU",
      "product": "PLA",
      "material": "PLA",
      "url": "/brand/sunlu/pla",
      "nozzle": "190–230 °C (374–446 °F)",
      "bed": "50–70 °C (122–158 °F)",
      "pricePerKg": null,
      "datasheetUrl": null,
      "affiliateUrl": null
    },
    {
      "rank": 2,
      "note": "PolyLite PLA lists 190–230 °C (374–446 °F), a bed of 25–60 °C (77–140 °F), and drying at 55 °C (131 °F) for 6 h. 200 °C (392 °F) and 60 °C (140 °F) from the pop thread sit on this row. 60 °C (140 °F) is the top of the bed.",
      "brand": "Polymaker",
      "product": "Polylite PLA",
      "material": "PLA",
      "url": "/brand/polymaker/polylite-pla",
      "nozzle": "190–230 °C (374–446 °F)",
      "bed": "25–60 °C (77–140 °F)",
      "pricePerKg": null,
      "datasheetUrl": "https://cdn.shopify.com/s/files/1/0548/7299/7945/files/PolyLite_PLA_TDS_EN_V5.4.pdf",
      "affiliateUrl": null
    },
    {
      "rank": 3,
      "note": "Bambu PETG HF technical data sheet. Nozzle 230–260 °C (446–500 °F), bed 65–75 °C (149–167 °F), drying at 65 °C (149 °F) for 8 h. The comments in this bank do not print this spool. It is the PETG row with a drying line.",
      "brand": "Bambu Lab",
      "product": "PETG HF",
      "material": "PETG",
      "url": "/brand/bambu-lab/petg-hf",
      "nozzle": "230–260 °C (446–500 °F)",
      "bed": "65–75 °C (149–167 °F)",
      "pricePerKg": null,
      "datasheetUrl": "https://store.bblcdn.com/ce12d65176a94f1086e6aefa238e62e2.pdf",
      "affiliateUrl": null
    },
    {
      "rank": 4,
      "note": "SUNLU PETG product page checked 19 October 2026. Nozzle 240–260 °C (464–500 °F) and bed 60–70 °C (140–158 °F). The catalog drying line is 60–65 °C (140–149 °F) for 6–8 h. Use that row rather than copying PETG HF's 8 h onto it.",
      "brand": "SUNLU",
      "product": "PETG",
      "material": "PETG",
      "url": "/brand/sunlu/petg",
      "nozzle": "240–260 °C (464–500 °F)",
      "bed": "60–70 °C (140–158 °F)",
      "pricePerKg": null,
      "datasheetUrl": null,
      "affiliateUrl": null
    }
  ]
}