[Build up of filament on printer head]

Started about an 8 hour print before I left the office. Came in next morning and print was hanging from head and now the head has major build up of PLA filament around the nozzle and inside. Got about a quarter of the way done before trouble seemed to start taking place. Here are a couple of photos:

Is there any way to remove the plastic without damaging hardware? Or is a replacement head necessary? Appreciate any help.

Thanks.

[Need round, smooth finish on cylinder]

Hey guys,

Recently bought an Ultimaker 2 Extended + and am still pretty new to this stuff. When printing a cylinder, it creates a hex like pattern with about 24 flat faces around, however it needs to be a smooth surface.  This is only a prototype and durability isn't of an issue.  I am using Ultimaker PLA.  The drawing came from AutoCad then Cura. It is going to be used as a demonstration for a product which has a smooth, round finish.  I printed the UM2 Cylinder that came on the SD card with the printer and it was much smoother around. Is this due to the wall thickness?

Was wondering if there are any settings to change to achieve this desired finish.  Again, I am new to this and would appreciate any help.

Thanks  

My print

UM2 Cylinder print