I have uploaded a new STL which has 2 main changes.
- Stronger arm and longer tube grip - the original version flexed quite a lot and ultimately mine broke at the base of the arm
- Slightly greater clearance below the arm to the large gear - I noticed that the gear was rubbing on the arm
The public onshape.com model has been updated.
Inspired by http://www.thingiverse.com/thing:766614 which did not fit the extruder heads on my TAZ 4, I have made this version.
It fits the two heads I have and, at least visually, seems to significantly reduce the stress on the filament at the entry point.
The design was created using onshape (http://onshape.com and I have made the design public there - just search "Lulzbot". If you would like the design in a more accessible format I can upload it in PARASOLID, ACIS, STEP IGES or SOLIDWORKS formats.
No broken filaments since installing so here's hoping that continues.
Obviously printed on my Lulzbot TAZ 4 in PolyMAX from PolyMakr (specialty PLA with great strength and flexibility characteristics. Given the small size, and the expected stress on the part, I printed at .1mm layers, 3 shells, 35% infill.
Revised version printed in PLA. Given the original broke. I increased the infill to 60% for the new print.