How to Fix Common 3D Printing Problems

• Thin strings between parts → Stringing / Oozing
• Corners lifting off the bed → Warping
• Layers separating or cracking → Poor layer adhesion
• Gaps in walls or thin, weak extrusion → Under-extrusion
• Rough, blobby surface → Over-extrusion or overheating
• Bottom of print is wider than it should be → Elephant's foot
• Print detaches from bed mid-print → Bed adhesion failure
• Rough or droopy overhangs → Overhang issues
• Lines visible in the Z direction → Z-banding

Fixes (try in order):

1. Enable retraction if it's off — this is the primary defense against stringing
2. Increase retraction distance — try 0.5mm increments (direct drive) or 1mm increments (Bowden) [1]
3. Increase retraction speed — try 35–50mm/s
4. Lower nozzle temperature by 5°C — less heat = thicker melt = less ooze
5. Enable "Wipe" in your slicer — wipes the nozzle at the end of each line before retracting
6. Increase travel speed — less time traveling = less time to ooze
7. Enable Z-hop on retraction — lifts the nozzle during travel to clear any strings

Fixes:

1. Increase bed temperature — make sure your bed is at the right temp for your material
2. Clean your build surface — oils from fingers reduce adhesion; use IPA (isopropyl alcohol) to clean the PEI/glass surface
3. Use a brim or raft — a brim adds material around the base to hold edges down
4. Reduce part cooling fan for the first 3–5 layers — rapid cooling causes differential shrinkage
5. Use an enclosure — essential for ABS/ASA, helpful for everything else on large prints
6. Reduce infill density — less internal material = less shrinkage force
7. Apply adhesive — glue stick, hairspray, or dedicated bed adhesive
8. Level your bed — an uneven first layer is the most common cause of adhesion failure

Fixes:

1. Increase nozzle temperature by 5–10°C — hotter plastic bonds better to the layer below
2. Reduce cooling fan speed — too much cooling prevents proper interlayer bonding (common with PETG) [2]
3. Slow down print speed — gives each layer more time to bond
4. Increase layer height — thicker layers have more thermal mass and bond better
5. Dry your filament — moisture causes steam bubbles that weaken layer bonds
6. Check for drafts — air blowing on the print causes uneven cooling and weak layers

Fixes:

1. Check for a partial clog — do a cold pull (load filament, heat to printing temp, cool to 90°C for PLA / 140°C for PETG, then pull the filament out — it should come out with a clean tip shaped like the inside of the nozzle)
2. Increase flow rate / extrusion multiplier — try 2–5% increases
3. Increase nozzle temperature — too cold = too viscous = not enough flow
4. Check filament diameter — measure with calipers at several points; if it's inconsistent (>±0.05mm), the filament quality is the problem
5. Slow down print speed — faster speeds need more flow, which may exceed your hotend's melt capacity
6. Check the extruder gear — worn teeth or incorrect tension can cause slipping
7. Check the bowden tube — gaps between the tube and the nozzle cause clogs and under-extrusion (common on Creality-style hotends)

Fixes:

1. Reduce bed temperature by 5°C — less heat = faster solidification of the bottom layers
2. Increase first layer Z offset slightly — less squish = less bulging (but not so much that adhesion suffers)
3. Add a small chamfer or fillet to the bottom of your model in CAD
4. Use "Elephant Foot Compensation" in your slicer — this insets the first layer by a small amount to counteract the bulge
5. Reduce first layer flow rate by 2–5% — less material on the first layer means less to bulge outward

Fixes:

1. Increase part cooling — overhangs need the plastic to solidify quickly after being deposited
2. Lower nozzle temperature by 5°C — cooler plastic is more viscous and droops less
3. Slow down print speed for overhangs — your slicer likely has an "overhang speed" setting
4. Use supports — for overhangs steeper than 45°, supports are usually necessary regardless of other settings
5. Reduce layer height — thinner layers have less mass to droop and better overhang quality
6. Orient your model to minimize overhangs — sometimes rotating the part 90° dramatically reduces the need for supports

1. Upload a photo of your failed print — the AI analyzes the visual symptoms and provides a diagnosis with specific fixes for your printer and filament
2. Use the Profile Doctor — upload your actual slicer profile file along with a description of the problem, and the AI identifies which settings are wrong and generates a corrected profile