Fused filament fabrication 3D printing relies on precise control of material flow through a heated nozzle. However, this flow is difficult to predict when the extrusion speed changes rapidly. A delay exists between the moment material is pushed into the hotend and the moment it exits the nozzle. The hotend therefore, behaves as a buffer, temporarily storing material and building up pressure. The resulting material flow depends on internal pressure and temperature.
To model this behaviour and characterise the performance of different hotends and nozzles, a dedicated experimental setup has been developed. This setup is capable of measuring both the extrusion force of the extruder and the resistance of the filament in the hotend.
An experimental measurement setup for filament resistance and extrusion force has already been developed. However, newly observed behaviour and irregular measurement results suggest that the setup's capabilities should be expanded. Once the measurement setup has been improved and validated, experimental data will be collected and compared with theoretical expectations.