Blobs, zits, and random surface defects appear when the printer starts/stops extrusion inconsistently or changes layers without smoothing. They don’t always affect strength, but they ruin aesthetics.
Symptoms:
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Random blobs on walls.
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Zits at layer start/stop points.
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Small raised bumps ruining smooth surfaces.
Causes:
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Retraction tuned poorly.
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Inconsistent pressure in nozzle.
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Poor seam alignment settings.
Troubleshooting Steps:
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Enable “coast at end” or “wipe” in slicer.
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Optimize retraction settings.
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Use “randomize seam” or “align seams” for consistency.
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Reduce extrusion multiplier slightly.
Prevention Tips:
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Use pressure advance/linear advance to improve flow control.
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Print at moderate speed for smooth walls.
