I have never had problems with moisture on abs. If you find bubbles like the pictures Erik shows. It can be a manufacturing problem. I have had that problem on one of my rolls. I sent it back and got a new one. Try to cut filament and see if you find bubbles. There should not be any.by birchman - Ormerod
HI. What infill percentage do you use. It could be that you are over extruding. If you use 100% infill. Try to lower the infill to 40%. If the problem disappear it can be that you are over extruding. If the infill is 100% and you over extruding the material is building up and as no where to go. That causes bumps. Very often in the corner where the layer change is done. If so you have to calibraby birchman - Ormerod