Hey all,

First time post here, I hope this is the right place (seems like there should be a specific subforum for the Ender-3, but I didn't see it).

I won an Ender-3 in a raffle at Christmas (including black&white spools of Hatchbox PLA), we had a honeymoon period for a few months, I would just throw stuff on there downloaded from thingiverse and sliced with Cura defaults, and it would just print. Once in a while I'd have to re-level the bed, but otherwise it was happy. Based on how much I have left on my kg spools, I guess I pushed about 700-1000g of filament through it.

Then I let it sit in the garage without printing anything for a month or 2 (SoCal -- it's not that cold), then hit it hard with a bunch of new projects (and some new filament: hatchbox grey PLA, and hatchbox green ABS (<-- accident))

Maybe it's mad that I ignored it for a while, because now the printer is very finicky. Now whenever I start a print I watch the first layer or two, and usually stop it, scrape the board clean, and restart once or twice before it gets a good foundation (bed adhesion problems I guess). If it's a short print (~1hr or less) there's a pretty good chance it will work out, but if it's many hours, usually somewhere it goes wrong and I'll come back to a pile of spaghetti.

Even ones that don't go as bad as spaghetti, will have one or two misprinted layers in the middle, so they break apart there. (Often I've just glued them together at the break with superglue or gorilla glue (the open waffle interior is good for gorilla glue which likes to expand))

I noticed that some filament was hard to push into and pull out of the tube (new grey I'm looking at you), so I've tried rubbing the filament with oil -- just one small drop over 6-8in, rubbed on with one hand, and then rubbed off with the other hand, to try to make sure the filament can go through the tube smoothly.

I've replaced the nozzle with the spare nozzle that came with the kit -- now how do I clean a nozzle? Or are they disposable?

I've tried leveling and re-leveling, at temperature -- but how hard should it scratch the paper? If the adhesion brim looks like paste or film on the bed, does that mean (that side of) the bed is too high? I've done micro-tweaks mid-print (1/8 turns of leveling knobs) if I think the printing looks uneven towards one corner. Do I need aquanet? Is the original bed-mat worn and needs replacing?

I've tightened the X- and Y-belts.

I've tried tweaking slicing settings in cura: decreasing resolution, increasing fill%, using a raft, etc.

Nothing works reliably.

Please educate me on what I need to do to maintain my 3D-printer, and get it back up to how well it worked when it was new.