Make Lehigh Valley Make Hardware, Make Software, Make Art

21Sep/140

Member Project Update: Frank’s Filament Extruder (WIP)

Hi All, the following is an update the Make Lehigh Valley Filament Extruder Project.  Thus far, the concept has been demonstrated successfully with production of several meters of ABS filament!!!

The emphasis on the project at this stage is determining fundamental parameters for operation of key sections of the design.  Key sections of the project include; nozzle design (nozzle diameter, length, inlet & outlet shape), material heater body design (single stage vs. multistage heating, heater element design including material, voltage, current, insulation), extruder design (length of extruder, hopper geometry) and drive mechanism (gear reduction, clutch, drive motor options).

Safety is a key design consideration for the project.  For example, low voltages are planned for powering of the heater element along with interlocks to protect against extruder or motor overload.

Next steps include; refinement of the heater element, incorporation of automatic heater control and testing of motor drive options. Once these items are tested satisfactorily, more sophisticated automation is planned.  The automation is expected to include an integrated control scheme incorporating heater controls, clutch slippage detection, drive motor controls and hopper feed sensing and controls.  Control platform and sensor options are still under review with the emphasis on safety, open source, simplicity, availability, cost and reliability.

Additional project details are provided in previous posts.

Comments and suggestions welcomed!

Frank Lyter

Prototype heater used to refine heater design requirements

Repurposed oven heater element - prototype heater used to refine heater design requirements

Final over heater fit up to nozzle

Heater fit up to nozzle - one of several bend configuration under consideration

Extruder heater test to evaluate operating voltages and currents

Extruder heater test to evaluate operating voltages and currents

Extruder heater testing for voltage and amp evaluation

Autotransformer used for voltage and amp evaluation

Heater element attached to extruder - subsequently covered in fiberglass insulation.

Heater element attached to extruder - subsequently covered in fiberglass insulation.

First filament production!!!  Evaluating various temperatures and pressures - sections with bubbles are when temperature was too high

First filament production!!! Evaluation ongoing for optimum temperatures and pressures - sections with bubbles are when temperature was too high

Posted by Frank Lyter