Hi everyone! I been about 2 years with a custom made printer, and I had one of the chinese PTFE lined hotends from Aliexpress, printing mostly PLA and a bit of ABS. I wanted to get serious about filaments, and bought a genuine E3D Chimera+. I've installed it, and altough it prints ABS beautifully, I can't print PLA reliably. Depending on the PLA, it can go mostly fine (Prima3D PLA+) with some expare underextrusion here and there, 50/50 chance with Sunlu PLA and I can't get a finished print of Eryone PLA. I've checked all the usual suspects: - The fan is the E3D fan included. It is mounted with the logo facing the heatsink (pushing air into it) and directly connected to 12V (it's a 12V setup) - I used the thermal compound included in the cold side of the heatbreak, as described - I already had semitec 104 sensors, so marlin already was configured with thermistor 5 - There's no fan pointed to the nozzles, and temperature is stable during the print - Retraction is never greater than 2mm, with 50mm bowden tube, and retraction speed from 20mm/s to 60mm/s - First layer is as perfect as it gets (can realiably print 0.1mm first layer) - Tried to print cold (185ºC), medium (200ºC) and hot (220ºC). No success. Remember I already had a perfectly (PTFE lined) working printer for 2 years, which I designed and build from scratch. Is PLA printing with all metal hotends allways this hit-and-miss??