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 just put it in my dryer at 40C for a few hours with little regard to a target humidity. I also live in a dry climate where the ambient humidity is low, so maybe it’s not enough in wetter climates, but this works for me.
23% is really just the bottom range of what your dryer will report. My dryer is 15%. Who knows what it really is below that, and whether those numbers are even accurate?
But after a day of drying at 50C you PLA will be bone dry regardless of what the dryer reports.
Try running your dryer with the lid propped open a bit. Most Sunlu dryers don’t have a way to get rid of the humid air pulled out of the filament.
This made an enormous difference. I kept the lid open a crack and the moisture dropped bellow 20 within an hour. The room RH is 30 btw.
I store my PLA and PETG in the bags they come in and have never done anything past that because I’ve never had an issue. I think people are far too concerned about filament being dry over a few filaments where it is actually important like Nylon.
Like everything in life: Depends.
A roll that will be gone within a few weeks? Don’t care.
Long-term storage (exotics)? Vacuum packaging.
Regular but will be open for months? No clue. My Xiaomi temperature & hydrometer go to 0%. In a nutshell, just throw orange gel in a watertight box and replace it once it starts turning colourless/green.
20% should be perfectly fine. I can’t get mine less than that without extreme effort, and it doesn’t performance better at that percentage anyway.
I dry mine in a food dehydrator and print with it in one of the filament dryers to keep it dry during long prints. I live in a swamp though, so it’s necessary for me to do this before almost every print.
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.
