TPU is a very soft material, and if it moves in and out of the nozzle repeatedly it can get stuck in the hotend. Lower the retraction distance to 2mm and decrease the retraction speed to 20mm/s to prevent clogging and underextrusion, the less retractions the better.

In the industrial manufacturing space, PLA is usually reserved for prototypes, while 3D printed TPU parts are found in many customizable end-uses that demand flexibility and strength. Generally speaking, TPU is more challenging to 3D print than PLA, which does not frequently cause jamming, stringing, or clogging.

The optimum layer height is usually 50% of the nozzle outlet diameter, but it can be lowered to 25% or raised to 75-80%. For a 0.4mm nozzle, an optimum layer height would be 0.2mm within a range of 0.1mm and 0.3mm.

Print temperature should be in the range of 210–250 °C. Bed temperature should be in the range of 40–60 °C. Print speeds should be limited to 15–20 mm/s. Layer heights of 0.2 mm or less help minimize the feed rate.