When do i need to change the PTFE tube of my ZT-HE ?

[luciancd]

Is there a "sign" to when i should change the PTFE tube on the ZT-HE ?

I am printing PC-MAX at 265°C. Do you have a guess on how many hours i can print
at such a high temperature @ Julia ?

I tried printing at 250°C - 260°C, but the support material seems to detach easier from the raft
during print at those temperatures.

Lucian

[Julia Truchsess]

After 10-20 hours of 260+ printing, the tube will probably look pretty nasty, but you may still not see any bad effect on prints. The tube's only function is to provide a low-friction path for the filament en route to the nozzle, while insulating it from the heat of the metal tube. As long as you're printing OK, there's not really any need to change it out.