For printing tpe / tpu and tires, it is preferable to use a 3mm extruder. With 3DPRN printers it is however possible to print these materials even with standard 1.75mm extruders by implementing some precautions and making some compromises.:

• Print at a very slow speed: with TPE there is a tendency to never go beyond 15mm / s in all printing phases
• Do not use too small nozzles: usually for printing rubbery materials it is preferable not to go below 0.4mm in diameter of the extruder
• Use steel nozzles: rubbery materials tend to slide better on steel nozzles rather than standard brass nozzles
• Do not perform retractions: it is necessary to make the extruder retractions null and void during printing
• Print at a high temperature: it is preferable to print at the maximum temperature of the range allowed by the material used
• Avoid squeezing the layers excessively: it is preferable never to lower below a layer height equal to 0.5 x <nozzle diameter>

However, it should be borne in mind that by printing TPE / TPU and rubbery materials with an extruder from 1,75 mm the rate of print failures can be high.