Diagnosing a print failure (SLS)
Diagnosing a print failure (SLS)
During a successful SLS print, the laser sinters powder to build parts layer by layer. After the parts cool, separate the printed parts from the unsintered powder. Post-process the printed parts and reserve the unsintered powder for reuse or disposal.
Normally, an SLS 3D printed part has a slightly grainy surface. If the temperature inside the build chamber is too hot, or not hot enough, the resulting temperature difference causes defects on the part’s surface. Obstructions in the laser path can also cause print defects.
Best practices
To reduce the likelihood of print failures, follow Formlabs instructions and perform routinely scheduled maintenance on your Fuse 1 generation printer:
- Use the recommended refresh rate for your material
- Adjust the bed temperature for optimal part quality
- Clean the optical cassette
- Clean the IR sensor and IR sensor housing
- Clean the print enclosure
- Wait for the internal temperature to drop to 30 °C (86 °F) before removing or handling the build chamber
Print defect overview
If you experience print defects with a Fuse 1 generation printer, consult the list below and visit the relevant support article to troubleshoot and resolve them.
Dimpling and pittingSymptoms:
Troubleshooting steps: |
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Layer shiftingSymptoms:
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Horizontal bandsSymptoms:
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Poor finish or orange peel texture on vertical surfacesSymptoms:
Troubleshooting steps: |
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WarpingSymptoms:
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Fragile partsSymptoms:
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Bumps along Z-axisSymptoms:
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Blurred or missing featuresSymptoms:
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DelaminationSymptoms:
Troubleshooting steps: |
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Powder contaminationSymptoms:
Troubleshooting steps: |
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Recoater artifactsSymptoms:
Troubleshooting steps: |
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Hard cakingSymptoms:
Troubleshooting steps: | ![]() |
















