Warping: the part lifts and its corners curl up

Likely causes

In order: the most frequent cause comes first.

1. 01Material shrinkage on cooling: lower layers cool before the upper ones and pull the edges up
2. 02A draught in the room: an open window, a fan or air conditioning chilling the part suddenly
3. 03Bed temperature too low for the material
4. 04A bed surface dirty with finger grease, dust or old glue residue
5. 05A high-shrinkage material such as ABS or polycarbonate printed without an enclosure

How to fix it

Apply one fix at a time and reprint the same test part. Changing three settings at once tells you nothing about which one worked.

1. 01

   Wash the sheet with hot water and dish soap

   Easy

   Finger grease is the number-one cause of adhesion failures and a dry cloth will not remove it. Wash the sheet in the sink with hot water and dish soap, dry it without touching the surface with your hands, and refit it holding it by the edges. On PEI sheets, isopropyl alcohol removes dust but not grease: that needs soap.

2. 02

   Raise the bed temperature and add a brim

   Easy

   Raise the bed to the high end of the material's range (60 °C for PLA, 90 °C for PETG, 100–110 °C for ABS, 110 °C for ASA) and enable a brim in the slicer. Prusa recommends a brim of 3 mm or more to improve edge and corner adhesion on large ASA parts, and 4 mm for polycarbonate parts over 5 cm.

3. 03

   Eliminate draughts

   Medium

   Close the window, switch off the fan and move the printer away from the door and the air conditioning. Prusa specifically warns that draughts around the print hurt results even for materials that in theory do not need protection. A cardboard box over the printer already changes things; a proper enclosure changes them more.

4. 04

   Change material or geometry

   Medium

   If the part does not need heat resistance, print it in PETG or PLA instead of ABS: the difference in shrinkage is enormous. If it must be ABS or ASA, round or chamfer the base corners, because sharp corners concentrate stress and are always the first to lift.

How to prevent it

• —Wash the sheet with soap every five to ten prints and always handle it by the edges
• —Use an enclosure for ABS, ASA and polycarbonate, with extraction or filtering for the fumes
• —Always leave a brim on large parts or parts with sharp corners
• —Place the printer away from windows, doors and air-conditioning outlets

Sources

1. [1]Warping | Prusa Knowledge BasePrusa Research · Manufacturer · accessed July 27, 2026
2. [2]ASA | Prusa Knowledge BasePrusa Research · Manufacturer · accessed July 27, 2026