Quote Originally Posted by thinkdifferent View Post
The problem is not quality: In long printing times, Temperature of the extruder increase and feeding PLA material can be melting. So Nozzle can clog. I've same problems in 6 hours prints. IMG_4810.JPG
It sounds like your extruder is overheating. Please make sure that the fan is installed properly, your prints are running at 230°C and you have ceramic insulation tape securely fastened to the heater block.