Update on my rough prints - turns out the drier was only half the fix

Same lesson here, just cost me three months of blaming my printer. I print mostly PETG and kept getting that fuzzy surface on tall thin walls. Tried every bed level and speed tweak I could think of before someone at my local makerspace asked how I stored the spools. Answer was a cardboard box in the garage, which gets pretty humid where I live in the summer.

Now I keep everything in a big airtight tote with a couple of those reusable silica packs, and I dry the spool the night before any long print. For PETG I run it around 65 for about six hours and that's been plenty. I also print from the drier when I remember, though honestly the tote alone fixed most of it.

One thing that helped me figure out what was going on: I printed the same small test piece from a fresh spool and from the old one back to back. The difference was obvious enough that I stopped second guessing my extruder. Might be worth doing if you still get the odd rough patch and want to know wheather it's moisture or somethig else like your retraction settings. Glad you got it sorted. That feeling when the surface comes out clean and you realize the printer was fine the whole time is a nice one.

Funny timing reading this, because I went through almost the reverse with a spool of PLA I'd left sitting on the shelf since last autumn. Dried it overnight like you did and the prints were still rough, and I nearly gave up on the drier entirely. Turns out a badly soaked spool just needs way longer than one night. Mine took about two full days at the drying temp before it finally behaved, and the surface went from sandy to clean somewhere in the middle of day two.

So if anyone tries the overnight thing and still gets fuzz, don't assume the drier is junk yet. Just let it run longer and check again. I also started weighing the spool before and after drying, mostly out of curiosity, and it does drop a few grams, which convinced me the water was actually leaving rather than me imagining progress.

One other thing I noticed is that the first stretch of filament after a dry seems to print worse than the rest. I figure the outer wraps on the spool catch the most air exposure, so now I just feed a foot or so through as scrap and let the fresh stuff from underneath take over for the real print.

I'd push back on the idea that the tote alone fixed most of it. In my experience that's exactly the trap I fell into. Sealed container, desiccant, felt pretty clever about it, and I still got the odd fuzzy patch on long prints months later because the spool had a bit of moisture baked in from before it ever went in the tote. Printing straight out of the drier is what actually killed it for me, same as the OP found. Storage slows the problem down, it doesn't undo absorbed moisture.

Reading this made me realize I'm basically doing the bag thing you described, except worse. I've got two spools sitting in ziplock bags in a cupboard and only print maybe once or twice a month, so they just sit there getting damp the whole time between uses. Still on the fence about buying a drier since my prints are mostly small stuff, but the rough patches I keep getting on PLA might explain themselves.

One thing I'm unsure about, and sorry if this is a dumb question, do you leave the drier running during the whole print? Mine's a cheap one without a fan and I'd be nervous leaving it on for hours unattended.

Printing through the top port worked for me too once I fixed the friction issue. My spool kept dragging on the edge of the hole and the extruder started skipping near the end of long prints. Printed a little chamfered guide that clips into the port and it feeds smooth now. Also stuck a cheap hygrometer inside the box when the lid is closed, mostly out of curiosity, and it's satisfying watching the reading drop over a few hours. Confirms the thing is actually doing its job instead of just guessing.

Update: spool's been living in the drier full time since I posted, feeding straight through the top port like before. The second commenter was right about soaked spools needing longer, I did one extra overnight cycle and that faint seam scar completly went. Storage between prints is sorted now too, no more bag guilt.