UMS5 Zits and blobs on the inside wall only

[yetAnotherUsername 4]

Hi all,

While printing with Ultimaker ABS using the nearly default CURA 4.11 Engineering Fine settings I am getting zits and blobs on the inside wall only, the outside wall is clean (the only changes to defaults are walls and top/bottoms set to 2mm and infill to cubic subdivision 15%). The printer is enclosed and the doors were closed. The room temperature is a bit high (30 - 31 deg C, but with low humidity - about 30%. PLA prints fine. With the next print (pics attached) I've also reduced the overall print speed (from 30 to 25 mm/s) and enabled coasting in experimental section), but it didn't help.

 

Interestingly the zits and blobs become much more frequent with height (the object I printed nearly took the whole print space of S5), so maybe it is a ambient temperature / cooling problem?

 

By the way, the external surface is not perfect either, some layers are wider than others...?

[Hammster 0]

Hello, I see similar zits and blobs on some of my prints. And, yeah, on the inside wall, not the outside. 
Did you ever resolve it, and if so, how?