No major new developments with the printer. I received white PLA from mendel-parts.com and have been using that after the green color all over my apartement started to hurt my eyes.
Green and white seem to behave pretty similar (which is not guaranteed!) but lately I had issues with the printquality being lower than with the previous extruder. For some reason the plastic was not always sticking to the layers below it, but tended to curl up a bit, leave a small void, and than deposit a blob a bit further instead of making a nice line. I tried cleaning the extruder hot-end, varying the temperature, varying the extrusion speed, but nothing gave major improvements. Last weekend I changed for the first time ever the layer thickness from 0.34 to 0.25 mm. This was a major change! Of course you get better details because of the layer thickness, but the plastic does not get the chance to escape anymore to curl up and it will always stick to the layer below.
Some pretty nice quality in the pictures below:
There is a drawback: both running skeinforge and printing takes much more time than before, but for now I can live with that. The remaining unwanted jitter in the surfaces which should be flat is due to many different small factors like: z-axis wobble, belt tension, x and y stepper gear train play etc.