Micro Swiss Install for Creality brand 3D Printers
After installing, heat the nozzle (200 for PLA is fine) and load your PLA of choice. While squeezing the extruder tension lever, you should be able to push the filament smoothly all the way to the hot nozzle and watch it ooze out. If you cannot, stop and find the obstruction. If the filament does not move smoothly now, the extruder will not be able to feed it properly.
Image by Distech Automation
Keep in mind that the maximum retract length is proportional to the length of the transition-zone and the length of the bowden tube (BT).
The maximum retraction length can be approximated as follows:
Max Retract Length = TZ length + (BT length / 250mm)
(i.e. With a 2.2mm TZ and a 380mm bowden tube length, you should use a retraction length of 3.7)
With the all metal hot end, a shorter retraction distance works better.
This is an important relation for bowden users to consider. If you retract longer than the TZ, molten plastic will be pulled into the Cold-Zone and will cool, fusing to the inside of the barrel and jamming the hot end.
Starting point for retraction settings:
1mm, 45 mm/sec
Raise Nozzle Temperature 5-10C over previous settings. If PLA brand recommends 195, raise to 205C
Temperature settings can stay the same
If you experience stringing, increase retraction distance by .5mm and try again.
If you experience jamming or any clicking of the extruder gear, there are a few things to try. First, make sure you've lowered your retraction settings to the above recommendations. Next, PLA is sticky and tends to adhere well to the metal hot end. So, dipping the tip of the filament into Canola oil before loading it, acts a seasoning for the metal hot end, like a cast iron pan. If you still have issues, let us know. Remember in the event of any jam, you must completely clear the filament path and make sure the filament will flow smoothly through a hot nozzle.