RepRap: Blog

Some were a little puzzled as to how the interior of the no-lathe extruder works. As I'm putting a few together, I took a photo showing how it combines the ideas of a simple locknut thrust bearing and a chopped-up drilled nut being used as the bearing behind the filament contact point. Files now online at http://www.thingiverse.com/thing:765.

Vik :v)

Labels: extruder, reprap, tamiya

Here's a shot of the extruder designed to use the Tamiya Universal Gearbox, no lathing required. The Tamiya shaft is replaced with a 2.5mm hex key, and that fits into an M5 grub-screw locknutted on to the top of the M5 extruder drive. There is a crude thrust bearing (locknuts & washers) inside, and half a drilled M5 nut to support the drive screw where the filament presses against it. It's mechanically complete but needs wiring up with a working opto board and a thermocouple - which are in the post. Yes, I know I'll have to paint the opto vanes or stick tape on them.

So Simon, here's your new extruder :) Actually I'll tidy up the models a bit and run you off a fresh one. The modelling has been done in BRL-CAD, exported with g-stl to STL format, then repositioned with ArtOfIllusion, saved as an STL again, converted to g-code by skeinforge and then sent to the Gcode RepRap "Phoenix" by the Java GUI program. It's a convoluted path but I kept on having snags at every darned step!

With the exception of the opto-board, all the pieces were sourced in New Zealand (which bodes well for other places). One day, I'd like to stick this on an I2C control bus so everything can be controlled from an Arduino without running out of pins!

It can take either a 16mm PTFE extruder barrel or the no-lathe heatsink one as shown. The clamp fixture is compatible with Darwin interchangeable extruder holders - I checked :) I'll post the files after their final tidying.

Vik :v)

Labels: extruder, pla, reprap, tamiya