What can cause stringing in FDM prints?

Stringing in Fused Deposition Modeling (FDM) prints occurs due to the presence of small strands or "strings" of filament that appear between the printed parts as the printhead moves from one location to another. This issue is primarily influenced by the printer's retraction settings and the temperature at which the filament is being extruded.

Excessive retraction settings, which involve pulling back the filament before the printhead moves to a new location, can lead to insufficient material being deposited during non-printing moves, while overly high temperatures can cause the filament to ooze from the nozzle even when it's not supposed to be printing. When the combination of these two factors is not optimized, it results in stringing as the filament can drip or ooze while the printhead is in motion.

By configuring the retraction settings properly—retaining a balance that prevents too much filament from being pulled back, yet enough to avoid oozing—and adjusting print temperatures to the lowest effective level that allows for good layer adhesion, stringing can be minimized.