Clogging and adhesion issue  

Re: Clogging and adhesion issue

Dirty bed will cause it.

Use ONLY the hot water wash before your next print, and do NOT touch the bed surface with your fingers, at all.

Hot Water wash: often, as needed
Handle the bed only by the edges.
Wash the bed in hot water, use a fresh paper towel as a wash cloth, with a few drops of plain dish soap (Dawn, unscented, no anti-bacterial, etc.). Rinse well in hot water - if you have very soft water, rinse a bit longer.
Dry the bed with a fresh paper towel.
Handle the bed only by the edges.
Place bed on printer.

Alcohol rinse: every few prints
Once in a while, an alcohol rinse is helpful to remove PLA residue. It does not remove finger oils.
Pour a 5 cm puddle of 91%+ alcohol in the middle of the bed, with clean hands use a fresh paper towel to scrub the bed. Wipe up all the alcohol.

Streak test: when contamination is suspected and after a wash
With a fresh piece of paper towel, and very clean fingers, dampen the towel with 91%+ alcohol, and wipe the bed side to side moving back to front, like you're painting it with alcohol. The alcohol should be thin enough on the towel it quickly evaporates. If you see any streaks, the bed is dirty and needs a wash.

Acetone wash: infrequent
Pour a 2 cm puddle of acetone on the bed, scrub it around with a fresh paper towel. It will evaporate fast as you clean. This step removes PEI oxides that form over time and with heat, and improves PLA adhesion to a like new state.

Re: Clogging and adhesion issue

Okay that goes definitely better! Since it's a brand new bed I thought it didn't need it but I was wrong. Thanks a lot

Re: Clogging and adhesion issue

So the adhesion is going very well, but i still have another issue that still occurred again just now...
The printing goes perfectly and then at some point it just stops extruding. Here are a few photos of the state:
https://drive.google.com/open?id=1RBGD2TevHUC_4m2Dq8qClvVcCQQwUF9-
https://drive.google.com/open?id=1DCoyiHfAiFAFeRQ3LLyGHQouMIfV0Px-
https://drive.google.com/open?id=1enRJ-l-vt8Oes3ciZdZzrVe-ntjV6F7L

So we can see it has been able to print more than a centimeter (already 7-8 hours) so still a decent height before stopping extruding. And the filament spool also has no problem, there is no tension on the filament.
What can be wrong here? I print with 220/60 settings. I can try colder but the other times I tried it stopped extruding after an even shorter time, even with the basic 215/210 Prusa PLA settings.

Edit 1: After the fail I did put back the nozzle temperature to 220, made a Load filament and pushed a little the filament and it came out without big issue, which frustrates me even more as it's not really clogged...

Edit 2 : I tried to make another print with Prusa PLA settings (215/210) for a way smaller print and it stops extruding after 10 minutes. On the spool it's indicated to print between 205 and 230, I'll maybe try at 225 then.

Edit 3 : 225 got worse, it just wrapped all around the nozzle.

Edit 4 : I still had some Prusa PLA filament, and I tried with all the default settings from Slic3r with 0.2 layer height but it still stops extruding after 1 or 2 millimeters.

Re: Clogging and adhesion issue

So I've made all the tries I mentioned in the "Edit" parts of my previous message. Still cannot make it extrude until the end... If anyone has a clue I'm really desperate, I spent the last few days trying to make it work without success and I'm running out of ideas.

As a temporary solution so I can print what I need I'm using some ABS I still had in my stock and here I have no issue at all, still with brand SUNLU.

Re: Clogging and adhesion issue

A simple thing is the tension applied to the idler gears in the extruder. Too much tension can be as bad as too little tension. Have you adjusted the idler tension since this began?

Which nozzle are you using? I assume it is the E3D-V6-175 0.4, the factory 0.4 mm brass?

Have you completed a PID calibration for the Nozzle Heater? There is a chance the heater is having recovery problems when the print fan blows over some surfaces and cools the nozzle too much. You can also test by printing with the fan at 25%, or off, to see if that helps.

It might be helpful to upload your .stl and .gcode (place in ZIP and drag ZIP into the text box).

Excessive retractions can cause a print issue, so if you have sliced using all of the default profiles for Printer, filament, and print ... all at default settings.

And, is there anything "unusual" about the gray filament? Does it have any special properties, UV resistance, titanium-dioxide filler, metallic flakes or glitter, etc? If the answer is YES to any of these, you might have a simple plug. A hard piece of plastic larger than the nozzle orifice, that a COLD PULL will remedy.

RE: Clogging and adhesion issue

I haven't been able to test everything you've mentionned - the forum was down yesterday evening (CEST) so I could not remember all the points - but so far I couldn't make it work when trying to manage the gears screws.

I've also made a cold pull since I tried with ABS - which worked except that the filament got big warpings during the night when colder but that's ABS issue.

For my nozzle I don't use the default one, I bought the "Hardened steel E3D V6 Nozzle" when I ordered the MK3 since a friend advised me to.

I'll try the fan thing tonight.