Inexpensive Piezoelectric Elements for Nozzle Contact Detection and Build Platform Leveling in FFF 3D Printers

Abstract

Inexpensive piezoelectric diaphragms can be used as sensors to facilitate both nozzle height setting and build platform leveling in Fused Filament Fabrication (FFF) 3D printers. Tests simulating nozzle contact are conducted to establish the available output and an output of greater than 8 Volts found at 20 °C, a value which is readily detectable by simple electronic circuits. Tests are also conducted at a temperature of 80 °C and, despite a reduction of greater than 80% in output voltage, this is still detectable. The reliability of piezoelectric diaphragms is investigated by mechanically stressing samples over 100,000 cycles at both 20 and 80 °C, and little loss of output over the test duration is found. The development of a nozzle contact sensor using a single piezoelectric diaphragm is described.

Keywords

• 3D printing
• open source
• RepRap
• calibration
• bed leveling