Small features overheat because the nozzle keeps returning to the same area before the previous layer cools. The problem is thermal accumulation, not only a high temperature setting.
Identify heat accumulation
- Sharp tips soften
- Thin pillars lean
- Small holes close
- Surface becomes glossy
- Stringing increases
Give each layer time to cool
Print multiple copies, set a minimum layer time, or move the nozzle away between layers. A small cooling tower can also give the part time to solidify without changing the whole profile.
Tune temperature and airflow
- Lower nozzle temperature slightly
- Increase part cooling within material limits
- Reduce extrusion width on fine details
- Slow the outer wall
Protect the geometry
Add sacrificial tips, fillets or extra material that can be removed later. For very small features, consider printing them separately or in a different orientation.
| Symptom | Thermal cause | Control | Action |
|---|---|---|---|
| Tip melts | Residence time | Layer time | Cooling tower |
| Pillar leans | Soft polymer | Temperature | Lower temp |
| Hole closes | Heat and flow | Speed | Reduce flow |
| Glossy surface | Overheating | Cooling | Increase fan |
| Stringing | Hot nozzle | Travel | Lower temp |
Common engineering mistakes
- Raising temperature to improve surface.
- Reducing cooling.
- Printing one tiny part at high speed.
- Ignoring minimum layer time.
- Judging from a single sample.
Checklist
- Is minimum layer time set?
- Is the nozzle temperature appropriate?
- Is cooling sufficient?
- Are small features supported?
- Is the test geometry realistic?
Send the small-feature geometry through the quote form for a profile review.