3D Printing Forum

Hi all,

Is it possible to regenerate the little drying bags that come with filament rolls? I think I read somewhere that they contain silica gel and can be dried in an oven. Is this the case and if so, what temperature and time?

Reiner

Yes, it' possible to re-use them. I used to work at a power plant where we used silica gel in large quantities to make sure that water didn't build up in some of the oil cooled transformers. And now and then we had to dry them up and re-use them. We just placed them on a tray in a regular oven and turned up the heat for a few hours, or maybe we did it over a weekend, and we just looked at them to see when they were ready as they change color. They are usually pink/blue when they are filled with moisture.

Looks like ~140C in the owen is appropriate. And unless you have a lot of bags it won't take long to dry them.

(Now I just wished that I had saved all those tiny bags I've thrown away all these years...)

I have a dehydrator (DIY beef jerky!). You should be able to use those to dry the silica.

Pretty sure you can jury rig something with a hair dryer as well.

Now I am browsing Amazon for dehydrators - not for the dry bags but to make beef jerky... thanks @nallath!

At work, I normally dry silica gel in an oven for like 6-8 hours, or over night, at 120 C.

So, assuming the stuff in the silica gel bags that comes with the filament is the same thing as what we buy as "silica gel" for keeping things dry at work, heating it in an oven for a few hours should do the trick!

You dry the whole bags or do you open them up..?
Have 3 pc. of 0.5kg bags lying around...

I would dry the whole bags. If humidity can go in, it should also go out and if you dry them at a more moderate temperature, they also shouldn't get damaged.

The maker is the best enemy of the housewife...

... I'm banned from the kitchen in general and from the oven in particular

Amedee wrote:... I'm banned from the kitchen in general and from the oven in particular

I would not dare to use the oven at home too, for the same reason..
Luckily we have good ovens at work, which we are allowed to use for drying things

One has to be careful, storing plastic pellets and boron carbide powder in some of our dinner bowls was not that popular, even thought it theoretically should be risk free according to all available information Moved all that stuff to work after the initial tests.

There are some bigger bags on Amazon that they say a few minutes in the microwave, that way you could say I'll make a cup of coffee dear, and quickly pop them in the microwave whilst you make you both a drink

might work, but I have no microwave - my honey banned it out of our flat.

Regarding oven, same at me but luckily she´s often at business trips. So try to dry next week (hopefully...)

drayson wrote: might work, but I have no microwave - my honey banned it out of our flat.

Regarding oven, same at me but luckily she´s often at business trips. So try to dry next week (hopefully...)

Banned a microwave? Medical device reason?

Nope, just "this thing kills all the good thing in our meals...." reasons.
On the other way round, it´s ok so I get more healthy food than microwave lasagne

But I found out that this little ovens for finalizing buns are very helpfull getting a perfect steak.
Maybe I try to dry with this as I can place it far away from direct view

It's not just a temperature thing. You need both temperature & airflow.

This is why ovens can be used for jerky (or drying fruits) but it just doesn't work that well. Dehydrators have a lot better circulation, which dries them way better.