Unresolved Black Spots in the prints like burned plastic

and.. I just got a new one and it was only finger tight... so... you have to know how.

SO.. all ya need to do is.. take it out.. hook up the heater and thermostat and heat it to 250. tighten down. I find this process tedious and difficult.
The stock nozzle only has those 2 flat sides and I'm ... i guess not dextrous enough to handle it.
I don't know what kind of torque guys are putting on them.. I'm putting a couple dozen inch/pounds (1+nm) on the thing. I'm sure I'm on the edge of breaking one side or the other. So.. torque at your own risk. But when I do that much torque, it really seems to work., even cold.

 

Yes it is required to tighten it while hot. Otherwise the thermal cycling will cause it to loosen. The hotter the better, just naturally keep your body parts away from the high temperature parts.

 

he means tighten while hot.
My experience says torque conquers all.. but I do both to be sure. Idea being if you deform the parts through torque far enough, you overcome thermal cycling problems.. or at least postpone them beyond the realm of care.
]torque to yield, but its dangerous to your parts in these cases.

Anyway, I have my super complicated way of tightening these things that requires like a 19mm wrench and a torch.. but people seem to do well with the method I basically transcribed above.

 

On day one I just grabbed mine with a wad of paper towel while hot and gave it a twist by hand. Been leak free since.

 

one day I grabbed mine with a polyester towel.. wet or not.. it melted.. ewwww.

 

That does not sound like a good idea to me.

 

it wasn't... I was frustrated... I thought it would be wet enough to not matter. It wasn't

 

I am currently away from my printer for the weekend. will try it and post the results. i tried to tighten it while it was cold and did not put a lot of force. I will try to tighten it with a little more force and see what happens.

Thanks a lot guys.

 

I tried the cleaned extruder and run for about 20 minutes. I did not see any leaks. I will try to print something big in a few days.