Stringing, blobbing, “zits”, oozing, or other fine artifacts showing up in your prints can be mitigated through the adjustment of several Retraction settings, and might indicate the printing temperature is too high. Retraction, during a print, is how the filament is briefly pulled back some (out of the hot-end) whenever the nozzle is finished depositing in one location and needs to move to another location without extruding anything. Adjusting retraction and printing temperature settings can help clear up these fine artifacts on your prints.
Temperature is too high:
Stringing and oozing may indicate that the printing temperature needs to be lowered some. Try lowering in 5 degree increments until you achieve the desired results, up until the filament will no longer extrude reliably, of course. For other artifacts, if retraction settings are not helpful in improving the appearance of your prints, then you will want to try adjusting the printing temperature.
Retraction Speed determines the speed at which your filament is reversed out of the hot end for travel moves and when changing direction during printing. We recommend keeping this set to less than 25mm/s to help protect the gears.
Retraction distance determines how much filament is pulled out of your hot end on travel moves and when changing direction. You will want to adjust this depending on temperature settings and filament type. Higher thermal retaining filaments such as PLA behave better with a longer retraction distance. We have found anywhere from 1mm to 3mm is a good starting range.
This sets the minimum travel distance of your print head in order to retract. If your print head is not moving this far during travel moves, it will not retract.
This option prevents your print head from traveling over holes in the X/Y plane when printing. This will slightly increase print time, but will prevent strings from getting caught on the holes during travel moves. We recommend keeping this setting on.
Minimal Extrusion Before Retracting:
This will prevent a retraction move, if your extruder has not put out Xmm of filament since its last retraction.
Z Hop When Retracting:
This will raise your print head Xmm while retracting. This setting helps prevent ooze, and strings from being deposited on your print.