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Nice tip, thanks!

Since the first post, i've had a few more observations that might seem pretty obvious to everyone, but weren't to me (straight away).

1) Silica gel isn't a dessicant. It's a moisture buffer. If its moisture content is higher than the ambient air's, it will make the air humidity rise. (That's actually how they use it in museums - to ensure any shifts in ambient humidity get buffered/evened out in exhibit cases.)
2) Silica get from a sealed bag of cat litter isn't necessarily dry. Mine increased the moisture in the box to 55-60%.
3) Before storage, microwave the silica gel in batches a few times. Do it on a plate (has to be high temp resistant), spread out as much as you can - the goal is to increase the surface area, not microwave as much volume you can.
4) Silica gel doesn't absorb moisture in its volume, but on its surface. Greater surface area = better absorption and higher capacity. That means smaller, more irregular and more spread out crystals are better than regular, huge chunks in piles.
5) Monitor the humidity for a few days or weeks after initial storage, if your filament was wet. The humidity in the box will drop at first, but go up days later, as the dry air absorbs the moisture from the filament. When the humidity stops rising, dump the silica out, left it all to air (in dry air) briefly, microwave the silica again, then pack everything up again.

Mine seems to be happy at a stable 25-30% humidity now.
For comparison, the local air's 60-90% these days.

Orcinus, that's very good advice. Just some minor nitpicking:

orcinus wrote:1) Silica gel isn't a dessicant [sic]. It's a moisture buffer. If its moisture content is higher than the ambient air's, it will make the air humidity rise.

That's mostly true. Silica gel has good affinity for water, so the equilibrium point occurs when the air is drier than the silica gel. That makes dry silica gel a good desiccant. It needs to be much wetter than the air to begin releasing its humidity, but yes, it does work that way too.

orcinus wrote:Silica gel doesn't absorb moisture in its volume, but on its surface. Greater surface area = better absorption and higher capacity.

Also mostly true. Short-term, absorption is on the surface, but the water eventually penetrates deeper. The immediate effect is given by the surface area, but over days and weeks, the bulk of the gel will get involved too.

benmeyer, do they recover their first color as they absorb moisture and is it safe to assume the same trick would restore them to their useful state?

Try uncooked rice as a desiccant. This works very well to keep the filament bone dry and is quite inexpensive. It's the old fashion way

I suggest you buy some filaments individually wrapped with dessicant as well:



Plastic quality is very important... We have a good article on this worth checking out : http://bootsindustries.com/portfolio-it ... -filament/

I picked up one of these at PetsMart. It's a pretty good size for spools and has a screw-on lid with o-ring seal. Some desiccant in the bottom and it should be good.

That’s a pretty nifty idea for filament storage. My ordered filament from 3d2print.net just arrived, and I don’t know where and how to store them. Probably I’ll try yours. Thanks for sharing this.

I wrap my filament in stretchy moving film. You can add a pack of dessicant, if need be.

Keeps the filament clean, and I can stash them anywhere without fiddling with more containers.

Miguel,

If you don't want to go with one of the ideas from Simon, Donald or tmccafferty, you could probably leave the filament at your filament store where you *cough*work*cough* "ordered" it from until you find room at home.

Really? A plug for your store doesn't even work in this thread.