Why is my filament brittle and snapping?

A spool that snaps on the way into the extruder is usually old, wet PLA. Dry it at the temperature published for that row, and reject it if it showed up brittle. Boiling it is a joke in the thread, not a process. Drying, storage, PLA printing, filament quality, and clogs are the pages that carry the detail.

Dry the row you have

PLA Basic dries at 50 °C (122 °F) for 8 hours. Prusament PLA dries at 45 °C (113 °F) for 6 hours. PolyLite PLA dries at 55 °C (131 °F) for 6 hours. The print windows are 190–230 °C (374–446 °F), 205–225 °C (401–437 °F), and 190–230 °C (374–446 °F). Drying temperature is not the nozzle temperature. The drying dataset is the table those hours come from. PLA is the hub.

Prusa's PLA article uses "brittle" for the printed part: it breaks along layers or into shards on impact. That stays true after you dry the spool. A dry PLA hook can still snap when you shock it. Hooks is the load case. Prusa's drying article is the source URL stored on the Prusament PLA drying fields.

Bambu's filament guide adds a second brittle case: filament that snaps inside an AMS channel, with certain PLA Wood and some fiber nylons on the example list. Dry those at their own rows before you call the AMS defective. Wood fill has the PLA Wood drying line, 55 °C (131 °F) for 8 hours.

The threads

r/3Dprinting 1myq0ge is the brittle-spool thread. The score-560 comment says refuse it if it arrived that way. The score-464 comment says PLA gets very brittle when it is old and moist, and that cheap filament is worse. There is no moisture percentage in the comment.

r/3Dprinting 1nff6t6 is the photo. The score-8 comment says 8 to 10 minutes in salty boiling water. The score-3 comment says wash the build plate. Skip both. The other three links are glow filament, a snap, and a sound that might be the extruder gear. No excerpt was supplied, so this page does not diagnose them.

Questions