This particular filament (Sunlu matte HS PETG) is one of the absolute worst I've ever used WRT being hygroscopic. It arrived so wet that I had literal steam from the extruder the first time I wanted to use it. It took almost 48h in my drier to dry it completely so I could use it. Its been sitting in an airtight box with dessicant for 5 weeks and I needed to dry it for >16h for it to be usable again. The wet part in this print was in the bowden tube between dryer and printer, I restarted the print after took this image.
Sure it prints well at 300mm/s, but it is by no means matte at the temperatures that allow printing it at high speeds, it is actually very glossy. A huge bummer.
smooth first layer...so nice
@ExcessShiv
I have bought some cheap petg noname stuff which prints without issues at 40% rh in the room.
Another roll transparent petg dont work without drying. Its strange.
Maybe it depends on additives how much water it will get into the material
Very strange.
I see there a lack of information from the manufacturers too. No one specifiy the needed storage conditions
They do state it is more hygroscopic than normal PETG due to additives that allow the fast printing, but this is still significantly worse than I ever expected. I also didn't expect to need to dry it for two days after unwrapping it just to print with it.