{
  "opening": "Prusa's ABS guide lists a nozzle of 255 °C (491 °F) and a bed of 100 °C (212 °F), with the bed allowed from 80 to 110 °C (176–230 °F) as the part gets larger, inside an enclosure so the air stays warm. Prusa's layer-separation guide says ABS cracks when cold air hits the print, and it says to turn the part fan off. A draft does the damage. The fan and an open room are the usual drafts.",
  "question": "Why do ABS and ASA prints crack between layers?",
  "slug": "abs_crack",
  "useCase": "abs",
  "useCaseLabel": "ABS",
  "updated": "2026-10-28",
  "shortAnswer": "Prusa's layer-separation guide says ABS cracks when cold air hits the print, and it says to turn the part fan off. Prusa's ABS guide lists a nozzle of 255 °C (491 °F) and a bed of 100 °C (212 °F), with the bed allowed from 80 to 110 °C (176–230 °F) as the part gets larger, inside an enclosure so the air stays warm. A draft does the damage. The fan and an open room are the usual drafts.",
  "recommendedMaterials": [
    "abs",
    "asa"
  ],
  "printerConsiderations": [
    "Prusa says to print ABS in an enclosure, or to turn on a draft shield in the slicer if there is no box. The enclosure page is [an enclosure for ABS](/answers/abs_enclosure).",
    "Prusa's fan article says ABS and ASA profiles keep the fan off for the first four layers and then near 15 to 20 percent. The layer-separation article says to turn the fan off completely for ABS. Both sentences are Prusa's. The stricter one is the cracking article.",
    "How to print the two plastics is [ABS](/answers/abs_print) and [ASA](/answers/asa_print). Layers that do not stick for other reasons are [layer adhesion](/answers/layer_adh). Corners that lift are [warping](/answers/warping)."
  ],
  "pros": [
    "The fan, the draft, and the 255 °C (491 °F) and 100 °C (212 °F) line are Prusa's guides, not a comment.",
    "Filament bands stay on the sheets, so a 100 °C (212 °F) bed is not pasted onto a sheet that stops at 95 °C (203 °F)."
  ],
  "cons": [
    "Prusa's PLA range of 195–220 °C (383–428 °F) in the cracking article is Prusa's, not the PolyLite PLA sheet.",
    "A comment's chamber temperature is that person's setup. It is not Prusa's enclosure specification."
  ],
  "community": "A comment says cooling an ASA print too fast left enough stress to break it. Another says ASA warps without a warm enclosure, and that a draft barrier can be enough for a small part that is not flat. A third says brittle ASA was moisture rather than the fan.",
  "related": [
    "abs_print",
    "asa_print",
    "abs_enclosure",
    "layer_adh"
  ],
  "faq": [
    {
      "q": "Why do ABS and ASA prints crack between layers?",
      "a": "Prusa's ABS guide lists a nozzle of 255 °C (491 °F) and a bed of 100 °C (212 °F), with the bed allowed from 80 to 110 °C (176–230 °F) as the part gets larger, inside an enclosure so the air stays warm. Prusa's layer-separation guide says ABS cracks when cold air hits the print, and it says to turn the part fan off. A draft does the damage. The fan and an open room are the usual drafts."
    },
    {
      "q": "Should the fan be off or only low?",
      "a": "Prusa's layer-separation article says to turn fans off completely for ABS, because cold air splits the layers. Prusa's fan article says the ABS and ASA profiles stay at 0 for the first four layers and then about 15 to 20 percent. Use the cracking article when the part is splitting. [Cooling](/answers/cooling) is the general fan page. [ABS](/answers/abs_print) and [ASA](/answers/asa_print) are the material pages."
    },
    {
      "q": "Does a hotter nozzle fix a split?",
      "a": "Prusa says layer separation comes from layers cooling at different rates, and that the fan and the room are the usual cause for ABS. For PLA, the same article says to raise the nozzle in 5 °C (41 °F) steps inside a 195–220 °C (383–428 °F) band if layers split. PolyLite ABS already lists 230–260 °C (446–500 °F). Stay inside the filament's own band and the printer's maximum. [Warping](/answers/warping) and [enclosures](/answers/abs_enclosure) are the shape and the box."
    }
  ],
  "sources": [
    {
      "title": "Prusa, layer separation and splitting",
      "url": "https://help.prusa3d.com/article/layer-separation-and-splitting-fdm_1806",
      "kind": "manufacturer"
    },
    {
      "title": "Prusa ABS guide",
      "url": "https://help.prusa3d.com/article/abs_2058",
      "kind": "manufacturer"
    },
    {
      "title": "Prusa, print fan",
      "url": "https://help.prusa3d.com/article/print-fan-is-not-spinning_2081",
      "kind": "manufacturer"
    },
    {
      "title": "PolyLite ABS technical data sheet V5.4",
      "url": "https://cdn.shopify.com/s/files/1/0548/7299/7945/files/PolyLite_ABS_TDS_EN_V5.4.pdf",
      "kind": "datasheet"
    },
    {
      "title": "PolyLite ASA technical data sheet V5.4",
      "url": "https://cdn.shopify.com/s/files/1/0548/7299/7945/files/PolyLite_ASA_TDS_EN_V5.4.pdf",
      "kind": "datasheet"
    },
    {
      "title": "Bambu ABS technical data sheet",
      "url": "https://cdn.shopify.com/s/files/1/0645/5876/0155/files/Bambu_ABS_Technical_Data_Sheet_V3.pdf",
      "kind": "datasheet"
    },
    {
      "title": "Community source, r/ElegooNeptune4 1ilaf7j",
      "url": "https://www.reddit.com/r/ElegooNeptune4/comments/1ilaf7j/",
      "kind": "reddit"
    },
    {
      "title": "Community source, r/ElegooNeptune4 1d692oj",
      "url": "https://www.reddit.com/r/ElegooNeptune4/comments/1d692oj/",
      "kind": "reddit"
    },
    {
      "title": "Community source, r/ElegooNeptune4 1dwxs2r",
      "url": "https://www.reddit.com/r/ElegooNeptune4/comments/1dwxs2r/",
      "kind": "reddit"
    }
  ],
  "recommendations": [
    {
      "rank": 1,
      "note": "Catalog nozzle 230–260 °C (446–500 °F) and bed 90–110 °C (194–230 °F). Prusa's 255 °C (491 °F) and 100 °C (212 °F) starting point sits inside that band. Heat dataset checked 21 October 2026 lists heat deflection 100 °C (212 °F) at 0.45 MPa and 98 °C (208 °F) at 1.8 MPa, ISO 75, and glass transition 101 °C (214 °F). Drying is 70 °C (158 °F) for 6 h, checked 18 October 2026.",
      "brand": "Polymaker",
      "product": "Polylite ABS",
      "material": "ABS",
      "url": "/brand/polymaker/polylite-abs",
      "nozzle": "230–260 °C (446–500 °F)",
      "bed": "90–110 °C (194–230 °F)",
      "pricePerKg": null,
      "datasheetUrl": "https://cdn.shopify.com/s/files/1/0548/7299/7945/files/PolyLite_ABS_TDS_EN_V5.4.pdf",
      "affiliateUrl": null
    },
    {
      "rank": 2,
      "note": "Catalog nozzle 230–260 °C (446–500 °F) and bed 75–95 °C (167–203 °F). Heat dataset checked 21 October 2026 lists heat deflection 103 °C (217 °F) at 0.45 MPa and 100 °C (212 °F) at 1.8 MPa, and glass transition 98 °C (208 °F). Drying is 70 °C (158 °F) for 7 h. Prusa's 100 °C (212 °F) ABS bed is above this datasheet bed.",
      "brand": "Polymaker",
      "product": "Polylite ASA",
      "material": "ASA",
      "url": "/brand/polymaker/polylite-asa",
      "nozzle": "230–260 °C (446–500 °F)",
      "bed": "75–95 °C (167–203 °F)",
      "pricePerKg": null,
      "datasheetUrl": "https://cdn.shopify.com/s/files/1/0548/7299/7945/files/PolyLite_ASA_TDS_EN_V5.4.pdf",
      "affiliateUrl": null
    },
    {
      "rank": 3,
      "note": "Catalog nozzle 230–260 °C (446–500 °F) and bed 90–110 °C (194–230 °F). Drying stored from the technical data sheet is 80 °C (176 °F) for 8 h, checked 18 October 2026. Prusa's fan-off instruction is a print guide, not this sheet.",
      "brand": "Bambu Lab",
      "product": "ABS",
      "material": "ABS",
      "url": "/brand/bambu-lab/abs",
      "nozzle": "230–260 °C (446–500 °F)",
      "bed": "90–110 °C (194–230 °F)",
      "pricePerKg": null,
      "datasheetUrl": "https://cdn.shopify.com/s/files/1/0645/5876/0155/files/Bambu_ABS_Technical_Data_Sheet_V3.pdf",
      "affiliateUrl": null
    }
  ]
}