3D Print Failures: The Most Common Problems and How to Fix Them

Why Do 3D Prints Fail?

Even experienced makers run into failed prints. The good news: most failures have a clear cause and a straightforward fix. This guide covers the most common 3D printing problems and exactly what to do about them.

1. Warping

What it looks like: The corners of your print lift off the bed during printing.

Why it happens: Rapid cooling causes the material to contract and pull away from the build surface.

How to fix it:

• Use a heated bed (60°C for PLA, 90°C+ for ABS)
• Apply a bed adhesive: glue stick, hairspray, or PEI sheet
• Add a brim in your slicer to increase surface contact
• Enclose your printer to reduce drafts (especially for ABS)

2. Layer Separation / Delamination

What it looks like: Layers split apart or crack horizontally.

Why it happens: Print temperature too low, or layer height too thick for the nozzle size.

How to fix it:

• Increase nozzle temperature by 5–10°C
• Reduce layer height to no more than 75% of nozzle diameter
• Slow down print speed to allow better layer bonding

3. Stringing

What it looks like: Thin plastic threads between parts of the print.

Why it happens: Filament oozes from the nozzle during travel moves.

How to fix it:

• Enable retraction in your slicer (start at 4–6mm for Bowden, 1–2mm for direct drive)
• Increase travel speed
• Lower print temperature slightly
• Enable “Combing” mode to keep travel moves within the print

4. Under-Extrusion

What it looks like: Gaps, weak layers, or missing sections in the print.

Why it happens: Not enough filament is being pushed through the nozzle.

How to fix it:

• Check for a partial clog — do a cold pull to clear the nozzle
• Increase print temperature
• Calibrate your extruder E-steps
• Slow down print speed

5. First Layer Not Sticking

What it looks like: The first layer peels off or doesn’t adhere to the bed.

Why it happens: Bed is not level, or the nozzle is too far from the bed.

How to fix it:

• Re-level the bed carefully — use a piece of paper as a feeler gauge
• Lower the Z-offset so the nozzle is closer to the bed
• Clean the bed with isopropyl alcohol before every print
• Slow down the first layer speed to 20–25mm/s

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