Poor layer adhesion means that printed layers do not bond strongly to each other, resulting in parts that split or delaminate along layer lines. This severely compromises the structural integrity of the print.
Common Causes
- Nozzle temperature too low — Insufficient heat prevents layers from fusing properly
- Layer height too large — Thick layers have less contact pressure between them
- Print speed too fast — Layers cool before the next layer can bond to them
- Cooling fan too strong — Excessive cooling solidifies layers before proper adhesion
- Under-extrusion — Gaps in layers leave less surface area for bonding
- Contaminated filament — Dust or moisture weakens inter-layer bonds
Recommended Fixes
- Increase nozzle temperature by 5-15°C to improve layer fusion
- Reduce layer height to no more than 75% of nozzle diameter
- Slow down print speed to allow better thermal bonding
- Reduce part cooling fan speed, especially for ABS and PETG
- Print in an enclosure to maintain stable ambient temperature
- Dry filament before use — 4-6 hours at appropriate temperature for the material
- Increase extrusion width slightly to improve layer overlap