Prusa Original MK2 fan nozzel

thingiverse

This is a modified Original Prusa MK2 fan nozzle shroud. The original fan nozzle did not fit well and also directed too much cooling towards the heated nozzle, which resulted in thermal runaway and a lowering of the hot end temperature during printing. I fixed my thermal runaway problem (and improved PETG printing) by doing three things: 1. I updated to the latest firmware version 3.1.0 (Nov 2017), which includes a thermal calibration for the PID. I calibrated it for 240 degrees (for my PETG filament) and 215 degrees (for my PLA filament). This calibration will help stabilize temperature during printing. 2. I adjusted the filament settings under the filament setting tab in Prusa Slic3r version 1.37.1 - for PETG, cooling is set to max 30%, min 15%, with fan disabled for the first three layers; for PLA, cooling is set to max 80%, min 75%, with fan disabled for the first three layers. 3. I replaced the fan nozzle with a new version included here.