How to Print ABS on the Kobra 3 Without an Enclosure
kobra3absno enclosurewarping
ABS wants an enclosure. The Kobra 3 doesn't have one. You can still print ABS if you manage the environment carefully — here's how.
Why ABS Is Difficult Open-Air
ABS shrinks as it cools. Rapid cooling from ambient air causes:
- Layer delamination (layers separating)
- Warping/curling at corners
- Cracking (especially tall thin parts)
Environment Setup
- Print in a room with no drafts — close windows, AC vents, fans
- Build a simple cardboard box enclosure over the printer (leave top slightly open for exhaust)
- Turn off the part cooling fan entirely (or max 10%)
- Run bed at 110°C to maintain ambient warmth around the print
Settings
| Setting | Value |
|---|---|
| Nozzle temp | 240–250°C |
| Bed temp | 105–110°C |
| Speed | 50–70 mm/s |
| Fan | 0–10% max |
| Retraction | 1.0–1.2 mm |
| First layer speed | 20 mm/s |
Bed Adhesion
PEI alone can work but:
- Apply ABS slurry (dissolve ABS scraps in acetone, paint thin coat on PEI)
- Or use Magigoo ABS glue stick
- Large flat parts: add 8–10 mm brim
Part Design Tips for Open-Air ABS
- Round corners — sharp corners are warp initiation points
- Add a brim on any print over 50 mm footprint
- Keep parts shorter/wider — tall thin parts delaminate
- Avoid large flat areas touching the bed
Ventilation
ABS fumes are not healthy. Always ventilate — crack a window, use a fan to move air away from your face, or wear a respirator with organic vapor filter.
When to Give Up and Use ASA
If you're printing outdoors or UV-exposed parts, just use ASA instead — similar print settings but better UV resistance and slightly easier to print.