I finally got a filament drying box and I’m using it prior to and during prints. It seems to be helping. I’m a bit of a color queen, so I keep a pretty big backlog of different filaments. I’ve been storing them in vacuum bags but the vacuum bags often seem to lose some of their vacuum after a few months; the whole process is a bit of a pain. Is this really worthwhile or as long as I’m using the drying box can I forgoe the vacuum storage? If vacuum storage is still a good idea, are there better bags I should be looking for that don’t lose some of the vacuum after a few months or is that pretty standard?
The big issue for long term storage and exposure to moisture is hydrolysis, in which over time water molecules infiltrate and alter the polymer chains of the filament, causing the mechanical properties to degrade. Hydrolysis is, to the best of my knowledge, not reversible by simply driving the filament as the water molecules become incorporated into the polymer chain.
That said, simply storing your filament in your vacuum bags and tossing in some dessicant pouches before you seal it should drastically increase the time you can store filament before running the risk of it degrading noticeably.
Personally I just have a large plastic bin with a rechargeable dessicant device that keeps things relatively dry and I haven’t had any issues storing filament long term.