# Why does my filament tangle / knot on the spool?

These comments do not show a knot forming on a spool. One pair argues about PETG squish versus PLA. Another says TPU is a limp noodle in a Bowden tube.

These comments do not show a knot forming on a spool. One pair argues about PETG squish versus PLA. Another says TPU is a limp noodle in a Bowden tube.

A spool knot is the strand crossing under itself so the free end cannot pull. A jam in the extruder can look similar from the outside. [Filament runout](/answers/filament_runout) is the sensor side of a stopped print. A [clog](/answers/clog) is the hotend side. [AMS](/answers/ams) is the feed path on a Bambu multi-material unit. None of those pages is a winding diagram, and neither is this one.
[Hatchbox PLA](/brand/hatchbox/pla) lists 180–220 °C (356–428 °F) and a bed of 50–70 °C (122–158 °F) on the product page checked 19 October 2026. [PolyLite PETG](/brand/polymaker/polylite-petg) lists 220–250 °C (428–482 °F), a bed of 70–90 °C (158–194 °F), and drying at 65 °C (149 °F) for 6 h. [Bambu TPU 90A](/brand/bambu-lab/tpu-90a) lists 200–250 °C (392–482 °F), a bed of 30–35 °C (86–95 °F), and drying at 70 °C (158 °F) for 8 h, with shore 90 stored on the row.

Updated 2026-10-23. Sources accessed 2026-10-23. Use case: Troubleshooting.

## Ranked filaments

| Rank | Filament | Nozzle | Bed | Price per kg |
| --- | --- | --- | --- | --- |
| 1 | Hatchbox PLA | 180–220 °C (356–428 °F) | 50–70 °C (122–158 °F) | — |
| 2 | Polymaker Polylite PETG | 220–250 °C (428–482 °F) | 70–90 °C (158–194 °F) | — |
| 3 | Bambu Lab TPU 90A | 200–250 °C (392–482 °F) | 30–35 °C (86–95 °F) | — |

## Sources

- [Hatchbox PLA product page](https://www.hatchbox3d.com/products/3d-pla-1kg1-75-blu) (manufacturer)
- [Polymaker PolyLite PETG technical data sheet](https://cdn.shopify.com/s/files/1/0548/7299/7945/files/PolyLite_PETG_TDS_EN_V5.4.pdf) (datasheet)
- [Bambu Lab TPU 90A technical data sheet](https://cdn.shopify.com/s/files/1/0645/5876/0155/files/Bambu_TPU_90A_Technical_Data_Sheet_582bf8f6-1f0a-474c-aeda-9e72af3689dc.pdf) (datasheet)
- [a Reddit thread in r/BambuLab](https://www.reddit.com/r/BambuLab/comments/1ltblc4/) (reddit)
- [a Reddit thread in r/FixMyPrint](https://www.reddit.com/r/FixMyPrint/comments/1bi2bsn/) (reddit)
- [a Reddit thread in r/FixMyPrint](https://www.reddit.com/r/FixMyPrint/comments/11uamyy/) (reddit)
- [a Reddit thread in r/3Dprinting](https://www.reddit.com/r/3Dprinting/comments/t8b5o0/) (reddit)
- [a Reddit thread in r/prusa3d](https://www.reddit.com/r/prusa3d/comments/1j1737e/) (reddit)

HTML: https://filamentfacts.com/answers/tangle