I watched a 3D printing youtuber say that Adam Savage said 20% but 10% is what he uses.
I have never seen my sunlu dryer show anything bellow 23% even after days of use and I have no idea how to achieve 10 without cooking the filament.
I live in a really dry climate, so I don’t really notice issues unless I have a spool out on the printer for months, and even then dust is more of an issue than humidity.
To be safe, I bought a storage bin with a gasket on the lid that I store all of my other spools in, and that has seemed to work great.
Yeah… I’ve been printing now for 11 years…
I’ve submerged PLA in water overnight and then printed it to prove humidity has no effect on PLA.
PLA doesn’t give a shit about humidity and never has. All the early days of 3D Printing that used Nylon needed drying out.
Even early days PLA getting brittle was about strain fatigue on the filament and nothing to do with humidity. But modern day PLA these days doesn’t suffer from those old school issues anymore.
Dust will cause more issues than humidity.
I’ve had issues with wet PLA filament that were solved immediately by drying it.
Likewise, I have had PLA get brittle and snap on the way to the extruder when left loaded on the printer and exposed in my basement for extended periods, but this behavior disappears after I bake it in the filament dryer, even on the same spool.
You solved that via annealing and releasing the stress in the PLA, not by drying it.