Remove nozzle?

[Bassna]

I have been trying to fix my left extruder for a few day's. It's clicking, won't extrude filament (barely does). I have taken the extruder assembly apart, and cleaned that all out. Still wont load filament through. I don't have anything 0.4mm or less to try to load through to clear the nozzle, home depot did not have a drill bit that small, guitar center sold me the wrong guitar string size! So other than ordering the right size string/drill bit online and waiting, I was going to remove the nozzle and try to heat it up to clear it out.

I heated it up to temp, and was trying to use a socket wrench to remove the nozzle, but it's really on there good. I don't want to try to turn it too hard and break it, but I did try pretty hard a few time's and it won't budge. So I just took a break from it again, and am currently just using the right extruder. Should I just not take the nozzle apart and order some guitar string or something and go that route? How are you supposed to replace the nozzle's?

[curious aardvark]

first - DONT heat it to remove. All that does is expand the metal and lock it tight to the thread.
Why anyone would think heating it up makes it easier is beyond me.

Do it cold.

Secondly, use the allen key that fits the lug above the nozzle to lock the heatblock in place. otherwise the bastard thing moves :-)

I've changed a few nozzles now and this is the way that works best.

Thirdly - change both nozzles at the same time.
Otherwise the new left nozzle will be longer than the old right nozzle.

What happens is that when printing rafts or the first layer, both nozzles will at times rub over the plastic and over time it wears the nozzle s down - at the same rate.
So when you change one nozzle you end up with different length nozzles.
I had athread a while back all about this.

The answer is to always change nozzles in pairs and keep them in matched pairs.

I have a ratchet wrench for the nozzles and - as said - I use the allen key in the extruder bolt to keep everything steady while changing nozzles.

The bugger of it is I currently have a matched pair with right nozzle being 0.5 and left being 0.4.
And I'm all out of 0.4 mm nozzles lol

Have to find out where dave got them from and buy a bunch of 0.4s.

[Bassna]

Haha thanks for all the info. I don't actually have any spare nozzle's on me at the moment. I was going to try to cook out the old plastic, and maybe get in there with something to clean out the rest before putting it back on. And that allen key that goes above the nozzle is in the back on mine, so I have to take the extruder off to get to it. I'll wait till my print is done and everything is cooled down and give it another shot.

[jfkansas]

I have removed nozzles both cold and hot. Hasn't been an issue either way. Generally though it is recommended to heat it up since the aluminum expands more than the brass and it loosens up a little easier. The threads don't have much metal behind them since the nozzle is bored out for the teflon tube. I have seen pics where some have twisted the nozzle off the threads.

[curious aardvark]

I've changed quite a few now. Not a problem.
Tricky if you don't have the allen key bolt to wedge the heatblock with though.

I have used gripper/plier thing but you have to be careful it doesn't damage the insulation. Mine does look a bit dogeared, still works perfectly well but you'd never sell it 'as new' :-)

[Bassna]

Update to this thread:

I was unable to actually get the nozzle removed. Not sure why. It's on there pretty good. So what I ended up doing was going back to Guitar center (they gave me the wrong size guitar string the first time I went =/ ) and got the correct 0.38mm guitar string. Then removing the extruder from the assembly, and using a small nut to keep the fan screwed into the heating block still, pre-heated the nozzle to normal temp.

Once pre-heated, I used a paper clip to get down in the hole, and just cleaned out what I could with it that way. I used a few paper clips because it got caked in plastic and hardened etc. I tried one toothpick as I read online, but it almost broke inside the hole, so I went back to paper clips. They won't break very easy! Cant imagine trying to fish out a piece of wood from there. Then took the guitar string, and feed it up through the bottom of the nozzle and up, going up and down getting the nozzle nice and cleaned. Hooked it all back up, and it's working great.

Next time I clean this thing out I will take a bunch of pic's and make a lil tutorial for people, cause it took me quite a bit to get it all cleaned out, and not much info out there for it. I first seen the guitar string idea from Geoffro on here. Helped ton's. I was emailing with Tang about it, and mentioned that they should include one guitar string with new purchase's. Would be a great tool and is almost guaranteed to be needed at some point I would guess.