Why Does My PLA Filament Keep Breaking?

I noticed my PLA filament was snapping in the PTFE tubes leading up to my Prusa i3 Mk3 multi-material extruder. So I've run a few quick tests on some straight PLA to find out what's happening. And I think I've got an answer. PLA filament, when held straight in a bowden tube after printing gets brittle and breaks into little pieces or snaps in the middle. It has to do with the plastic wanting to stay wrapped in the same shape on the spool. Follow up experiment showing mechanical stress on PLA:    • Will 3D Printer Filament Break in PTF...   PCBurn Article: pcburn.com/why-does-my-pla-filament-keep-breaking/

• #science_technology
• #pla
• #snap
• #break
• #brittle
• #filament
• #3dprinting
• #ptfe
• #bowden