Just when I thought I got the machine printing the way I want I take a model with a couple of fine details sticking up… and the printer messes things up. PLA, fan constantly on, 14 seconds per layer, funning moderately slow, like 17-20 mm/s… The rest of the model is fine, but the top little cubes, of which there are 4 - the layers just don’t eem to stick to each other. Advice anyone?
Looks to hot and up the retraction.
Had something similar and it was my extruder that was not extruding enough material.
Measure 10mm of filament, extrude 10mm and see how much it was pulled, adjust and repeat untill 10mm = 10mm
@Andre_Courchesne1 , extruder calibration is 10x better it you use 100mm.
Not knowing what it’s supposed to look like, the problem could be calibration, retract settings, still too much heat in the part, or extruder moving too slowly to work well (and still heating the part by proximity). Maybe add a pillar to the print off to the side to allow the part to cool and keep the extruder flowing at a happy rate.
@Dale_Dunn True, just being cheap 
I’ve had some luck by adding a small desk fan next to the printer to add extra cooling to the whole part.
@Wayne_Friedt upped the temperature already… will try upping the retraction.
@Andre_Courchesne1 , Extruder calibration is what I started with - by now it seems to be extruding the right amounts (i.e. if I decrease flow a bit it starts leaving gaps, and if I increase it - the print starts leaving small borders at each pass)
@Dale_Dunn it’s a weird problem for sure, I can’t even describe it properly. I also thought it could be too much heat in the part but certainly it’s not the issue now - 1) there is a ducted fan blowing right at the extruded plastic 2) the problem gets worse if there are several small spots to fill in one layer - that’s what is illustrated by the photos above. It’s a frame that has several elements sticking up, 4 of these are quite small and diminishing in size towards the tip. Like 4 small pyramids at the top of a larger structure. And the smaller the layers get the worse - all larger areas are printed perfectly (ans surely under or overextrusion would show up elsewhere?)
@Carlton_Dodd unfortunately it’s more tricky than cooling. It looks like a decrease of strength of bonding between layers when the layers are too small, and then the hotend tip itself could disturb the upper layer by either rubbing against it or against any small filament strands left by retraction, and dragging the layer away… Something like that, but how to test it? And more importantly - how can this be fixed?