Printed the Aria dragon last night on my Mendel90 with standard J-Head. Half way up, things started going south. I was really happy with the results until then. Any ideas what could bring it on? Layer height 0.1mm Sliced in S3D The filament is PLA from RepRap Walmart.
Looks like the longer the travel distance the worse the glob, might need more retraction on travel movements.
I’ve been looking at printing speed vs. retraction vs. object density on my Mendel90 in a bid to stop the blobs at line start/end.
I’ve found that slow printing speed i.e. 20mm/s and 0.5mm of retraction at 80mm/s give the best results.
The blobs appear to increase in size again over 80mm/s retraction and 20mm/s printing speeds.
With additive manufacturing things should only go North 
Still looks good though.
I would try 1mm retraction and I actually use 1.5mm as my setting as I work with materials at higher temps.