Print head breaking printed parts

Hi - which category would I use to get advice on solving a problem?
I tried printing Anish’s Colosseum on my Creality Ender-2 but ran into a problem I can’t figure out.

Everything proceeds fine until the columns on the first tier are to be topped with another complete layer (Cura tells me it’s layer around layer 115 but I haven’t actually caught the failure). I initially printed this using HatchBox Black PLA which mostly worked (only a couple of leaning columns). I tried using Gizmodorks White but still has more than 15 columns broken. Initially I thought it might be warping in the build surface so I tried a glass surface with no difference. I really could use some advice.

by looking at your image I can see that the top of the remaining columns are curled up a little bit, I think it’s a temperature/cooling problem, try to bump up the part cooling fan speed or maybe lower the extrusion temperature by a couple of degree.
Z hop can help too: basically before moving to another position it rises the nozzle up by a certain amount hence avoiding knocking off tiny elements such as your columns. In my experience z hop increase stinging a little bit but it’s better to have to clean up a bit a succesful print than have no print at all :wink: A z hop between 0.5 and 1mm should work just fine

I hope that this will help.