I finaly upgraded my 3D printer:
1️⃣ switched from #
Repetier to
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Marlin firmware
2️⃣ replaced heat bed thick PEI foil mounted by paper clamps by magnetic PEI covered steel sheet
3️⃣ replaced defective extruder termistors
#
DnesBastlím #
3DPrint #
DIY #
Upgrade