BOM
- Lulzbot hexagon hotend $70 https://www.lulzbot.com/products/lulzbot-hexagon-hot-end
- 24V/4-5A power supply
- 3mm id x 6mm od PTFE tubing 630mm long
- 2x M6 x 0.8mm hex nut
- 3mm print effector
- 3mm extruder drive body
- ~1m 18ga speaker wire
- 2x ~1m 28ga twisted pair
- Heat shrink tubing
OpenSCAD design
- End effector - download latest version of [Athena SCAD files] and [SCAD libraries]. Change the Bowden dimensions in athena.scad. Render the end effector and print.
- Extruder drive - download latest version of [extruder drive SCAD files] (requires the SCAD library, as above). Change the filament dimensions in extruder_drive_renderer.scad. Render the extruder drive body and print.
Build Instructions
Test conditions on Athena RepRap 3D printer
10/23/15 - Test 0
Filament: Maxpower 333605 Residential Grade Round .105-Inch Trimmer Line 690-Foot Length from Amazon for $24.35/3 pounds (1.3kg $18.73/kg) End effector: 3mm Athena print effector Hot end: Lulzbot Hexagon, 3mm x 0.35mm Extruder drive: 3mm Phidias extruder drive Firmware: Franklin (latest) Temperature: 260 C Print speed: Variable (testing capabilities) Slicing: Cura 15.04 set to 3mm filament, 1 multiplier, 0.2mm layer height, 70mm/s, 25% infill, 30mm/s initial layer speed Bed: Glass mirror with glue stick Notes: First layer too close to glass requiring decrease in speed. Using a 12V fan on the end effector with pwm. Fan speed too high, end effector would not reach target temperature. Occluded lower half of fan with masking tape.
Result:
- Adjusted speed up to 140% (98mm/s) while printing first ~100 layers
- Lower layers exhibited poor interlayer bonding
- Resulting print is flexible, but makes cracking noise when squeezed due to poor interlayer bonding