... graphite is brittle and you have to polish/ream the inner bore for perfect feeding, while PTFE tubing is ready to use - and yes, more heat-resistance would be fine ... but you didn't really want to heat the plastic to higher temps than actually used ...
Viktor
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Aufruf zum Projekt "Müll-freie Meere" - [
reprap.org] -- Deutsche Facebook-Gruppe - [
www.facebook.com]
Call for the project "garbage-free seas" - [
reprap.org]