PET bleh.
Que te a pasado?
Needs a sock 
Whats and efectuar way to clean that being PLA?
Wow. Did you ever try to scrub it off with a tooth brush at extrusion temp? My hot end looks barely used in comparison, but I don’t let stuff just bake on.
wow, thats pretty bad! Crank the heat to 300 and kock that crud off. I’ve had good luck with cotton swaps ( qtips… ) recently but a nylon bristle brush would also help especially for the initial cleaning
I’ll give heating and scrubbing a shot when I’m back in the lab.
Bring it up to around 180c, pull off with needle or tweezers while it is soft at its contact but firm enough to help remove itself. I had about a third of that mess once and that’s what I did, it came away all as one without much trouble. I caught it immediately though it wasn’t baked on. Not sure if it has been through a lot of heating cycles it could be harder to deal with.
I take mine apart stick it in a vice and heat it with a oxy acetylene torch till it’s all gone. Low heat by what it’s capable of or you’ll wreck it just about what you would get with a lighter.
Know this problem. Pet is actually nice to print but this is its biggest downside…sad.
PET. I always get this build up after a few (dozen) prints. Found a soft brass brush @ temp is the best method. Cleans off nice and easy.
I try to keep my head clean as well, but seriously thinking about the new E3D Silicone Sock. Just not thrilled with having to upgrade to the new screw in thermistor.
@John-Paul_Hopman yeah but its awesome 
If mine was broken, would already be in the mail. But replacing something that works? Feels wrong.
@John-Paul_Hopman cartridge works better 
Yeah My old blocks were like that, replaced them with the Thermistor cartridge blocks and heating is much more accurate. Worth it, just need to pick up some socks…