Glimmer of Hope

I'm on my Nth rebuild of the extruder and I think I'm finally getting somewhere. Things I've learned:
- Lubricating the filament helps a lot. I've now got a piece of oil-soaked cotton strapped to the inlet of the extruder.
- The bolts holding together the two halves of the extruder body should move freely in the holes. If they're too tight, drill out the holes.
- Keep the drive speed down. I can push the extruder to 12mm/s but 8mm/s is more reliable.

I've currently got the extruder clamped to the frame to make testing easier. I've been timing the 250mm drop from the nozzle to the tabletop to determine extrusion speed.

Next step is to mount the extruder on the carriage and recalibrate the Z axis.

If all else fails, I can always order a new extruder from BitsFromBytes. The new design looks pretty good.