Odd extrusion issue

I recently purchased an Anet A8 printer and it was working like a dream up until about a day ago when it started having an issue where it extrudes a second bit of filament during prints that curls and clings to the nozzle and ultimately ends up ruining prints that go longer than a few minutes. Additionally, my nozzle is absolutely covered in plastic, but that may just have to do with the previous issue. If anyone has any idea as to what I should do, your help would be much appreciated.

If its relevant I'm printing using Hatchbox white 1.75 PLA at between 190 and 200, normally 200

To start with take the filament out of the extruder (set it to preheat and as the temperature comes up to 120C, press the release button and pull the filament out). Then let the preheat get up to temperature (a small amount of filament may ooze out of the extruder) and using a pad of non-synthetic cloth, wipe all the filament off the outside of the heater block and nozzle.

Switch to cool down and then let everything cool. Replace the filament (this can be done absolutely cold) and preheat. Using the manual controls run two or three lots of 10mm of filament through (clear of the bed). If this flows alright you are good to go. If not then you will need to strip and clean the nozzle and throat tube.

Filament not sticking is normally a sign that the temperature is too low and it then curls up round the nozzle. Make sure that you have enabled retraction in your slicer also try increasing the extruder temperature during printing by 5 degrees.

Edited 1 time(s). Last edit at 01/23/2017 12:31PM by Supermec.

Filament sticks to the bed perfectly, theres just some extra curling plastic that comes out too. I'll try doing a cold pull later though to see if theres any nastiness in there

Griff4218 Yes, but normally the print cooling fan isn't on for the first layer, this may be having an effect.

Finally discovered what the issue was, my nozzle had a small hole about 0.1mil in size on the side, possibly an unfortunate air bubble from its casting. New nozzle is on the way now