Why do 3D prints warp?

Warping is caused by differential thermal contraction. Each layer deposited on top of a cooling layer pulls in a different direction as it contracts. The accumulated stress is highest at the corners of the print, which lift off the bed. Materials with a high coefficient of thermal expansion (CTE) — ABS, ASA, Nylon, PC — warp far more than PLA, which has a low CTE.

How do I stop my 3D print from warping?

The most effective fixes are: (1) increase bed temperature to its maximum for the material; (2) add a brim (8–12 mm wide) to increase first-layer contact area; (3) use an enclosure to maintain ambient temperature above 40°C; (4) turn off the part cooling fan completely for high-warp materials; (5) add a draft shield in the slicer. For ABS and Nylon, all five of these measures may be necessary simultaneously.

PETG warps less than ABS but more than PLA. On standard-sized parts, PETG usually prints without warping at 70–85°C bed temperature. For large flat prints (footprint over 150 mm), add a brim and increase bed temperature to 85°C. PETG does not require an enclosure to prevent warping.

How to Fix 3D Print Warping

Warping — where the edges or corners of a print lift off the build plate during printing — is one of the most common FDM failures. It is completely preventable once you understand why it happens and which combination of fixes is appropriate for your material.

Why warping happens

Every plastic contracts as it cools. The problem is that each new layer is deposited at printing temperature onto layers that are already cooling and contracting. The top layer wants to shrink, but the bottom layer resists. This creates internal stress throughout the part. In low-warp materials like PLA, this stress is small and the part stays flat. In high-CTE materials like ABS, ASA, and PC, the stress is large enough to physically lift the corners off the bed — sometimes dramatically enough to knock the print over mid-print.

The solution is to reduce the temperature differential between the printed layers and the ambient environment — either by keeping the ambient hotter (enclosure) or cooling the material more gradually.

Warping risk by material

Material	Warp risk	Min bed temp	Enclosure?	Notes
PLA	Low	55–65°C	No	Warps on very large flat prints in cold rooms. Usually manageable with a brim.
PLA+	Low	60–70°C	No	Similar to PLA. Slightly more flexible, slightly less warp-prone.
PETG	Low–Medium	70–85°C	No	Generally well-behaved. Warps on wide flat prints without brim.
ABS	High	100–110°C	Required	Severe warping without enclosure. High CTE causes corner lift even with brim.
ASA	High	100–110°C	Required	Same behavior as ABS. All ABS warping fixes apply directly.
Nylon PA6	Very high	70–80°C	Required	Moisture and thermal expansion combine for severe warp. Dry first.
PC	Very high	100–120°C	Required	Highest CTE of common materials. Active chamber heater recommended.

8 proven fixes for warping

1. Increase bed temperature to maximum for the material: Hotter bed = slower cooling of the first layers = less warp. ABS: 100–110°C. PC: 100–120°C. Nylon: 70–80°C. If your bed cannot reach these temperatures, consider whether your printer supports the material at all.
2. Add a brim: A brim adds extra perimeter lines around the base of the print, increasing the contact area between the first layer and the bed. This provides mechanical resistance against corner lift. Use 8–12 mm brim for ABS and 5–8 mm for PETG. Brim is free — there is almost no reason not to use it on large prints.
3. Use an enclosure: An enclosure maintains a warm ambient temperature around the print (40–55°C), dramatically reducing the thermal gradient between printed layers. Required for ABS, ASA, Nylon, and PC. Even a simple cardboard box around an open-frame printer helps.
4. Turn off part cooling fan: The part cooling fan actively cools the printed layers. For high-warp materials, cooling accelerates the contraction differential. Set fan speed to 0% for ABS, ASA, Nylon, and PC. PLA and PETG need fan for good overhangs and bridges, so keep it on for those.
5. Clean the bed surface with IPA: Fingerprints and oils on the bed reduce first-layer adhesion. Even if the first layer appears stuck, an oily film prevents the mechanical bond that holds the print down. Clean with 90%+ isopropyl alcohol before every print on problematic materials.
6. Use a bed adhesive for the first layer: Glue stick (Elmer's), Magigoo, or hairspray can improve first-layer adhesion for ABS and Nylon on PEI surfaces. The adhesive does not bond structurally — it increases the coefficient of friction between the material and the PEI surface, resisting the sliding motion that causes warp.
7. Add a draft shield in the slicer: A draft shield is a thin-walled perimeter printed around the entire part. It traps heat radiated from the part and reduces the effect of room airflow. Enable it in your slicer's support settings. Useful when an enclosure is not available.
8. Reduce print speed for the first 3 layers: Printing the first few layers slower gives the plastic more time to bond to the bed surface before shrinkage forces act on it. Use 20–25 mm/s for the first 3 layers on high-warp materials, then increase to your normal speed.

Find settings for your material

ABS printing guide →Nylon settings guide →High-temp materials guide →ABS settings database →