filament storage  

Re: filament storage

Zip-loc bags and dessicant work well at keeping filament dry. If it's saturated, you'll need to dry it in an oven or heater of some sort.

Re: filament storage

I keep my unsealed filaments in big, watertight plastic boxes (like 10 rolls per box) with some big dessicant bags.
Got 4kg of dessicant and 10 nylon mesh bags for around 40 Euros, the watertight storage boxes from the local hardware store.

Re: filament storage

Thanks 😀

Re: filament storage

Since similar questions come up quite often, does anyone know of a site/article, etc. that compares/rates the hygroscopic properties of filament by plastic type? I've done several searches for such a reference several times, but not found anything very comprehensive/inclusive.

N.B. Of course there will be exceptions & variables--some types of PLA may absorb moisture more/less than others or even other plastics, but some kind of general comparison might be helpful when this topic comes up. 😉

Re: filament storage

I use gallon size freezer bags with a 50g packet of desiccant. It is a bit tight getting the spools in, but seems to work. Something slightly larger than 1 gallon size bags would be ideal.

Steve

Re: filament storage

Something slightly larger than 1 gallon size bags would be ideal.

Is there such a thing as 4 liter size bags (or is that not slightly larger enough)?

Re: filament storage

Since similar questions come up quite often, does anyone know of a site/article, etc. that compares/rates the hygroscopic properties of filament by plastic type? I've done several searches for such a reference several times, but not found anything very comprehensive/inclusive.

N.B. Of course there will be exceptions & variables--some types of PLA may absorb moisture more/less than others or even other plastics, but some kind of general comparison might be helpful when this topic comes up. 😉

You haven't seen this comparison because it doesn't really make sense to make such a thing.

Every material has a state where it's stable and doesn't absorb moisture. This state depends on material, relative humidity and temperature. It's called "Equilibrium moisture content" if you want to search for that. What's actually happening is that by changing the relative humidity (with pallets) or ambient temperature (dry box/oven) you're moving along an EMC curve for this material.
The question is what exactly you want to know? How fast you can move on the EMC curve for the specific material (PLA/ABS/PETG..)? Or the actual EMC curve for the materials? Because you have always 3 variables changing over time. Have fun to put this in a sheet 🙂

That's why you usually get the information like one material is more hygroscopic then the other. Means it has higher EMC curve and can hold more moisture.

I hope it does make sense.

Re: filament storage

Something slightly larger than 1 gallon size bags would be ideal.

Is there such a thing as 4 liter size bags (or is that not slightly larger enough)?
I've got 2 and 5 gallon bags. 2 is just right. 5 is way too big.

Re: filament storage

I use air tight 5 gallon buckets.

Re: filament storage

Let's not forget that where you store it is important too. Airtight containers in a climate controlled room is different from airtight containers in a garage in SW Florida. Its fine in the container but some of those filaments are like a sponge in the open air. For instance, in my case, TPU will begin the "spit and pop" within minutes of me breaking the original vacuum seal and printing.

I like to store in a big vacuum seal bag. The ones you can get for storing winter clothes during the summer. Pack them in and use the vacuum cleaner to suck out the air. Less air less humidity and, hopefully, the more likely the moisture is to "boil" out and get sucked up by the desiccant.

Neal

Re: filament storage

Good idea, Neil, for longer term storage!

To all:
I have only started to store my filament in a drybox with dessicator some 2 weeks ago and didn't print anything in the meantime.

I recognized that for some filaments it's recommended to dry them before printing.
According to your experience, is it still necessary to dry filament if it was stored in a sealed bag/box with active dessicant?
Can the dessicant dry filament that has absorbed some moisture?

Re: filament storage

To all:
I have only started to store my filament in a drybox with dessicator some 2 weeks ago and didn't print anything in the meantime.

I recognized that for some filaments it's recommended to dry them before printing.
According to your experience, is it still necessary to dry filament if it was stored in a sealed bag/box with active dessicant?
Can the dessicant dry filament that has absorbed some moisture?

Desiccant should absorb moisture easier than filament. That is its purpose so I suppose it should act as a sacrificial item. But I don't think it can absorb what is already in your filament. I can only print on the weekends so the vacuum bag works best for me. If it still has its seal unbroken I know that it has not absorbed any more than was already "in the bag" so to speak and the desiccant probably got most of that. However I also have a food dehydrator that can hold 8 2K spools at a time and use that on spools that have been opened a month or so.

Honestly you should start off small. Get some zip lock freezer bags (freezer are made of heavier gauge plastic and tougher IMO) and save all your desiccant bags that come with your filament and toss those in when you store them. You should know that the desiccant can be dried out too at times as it can become saturated. Then go from there.
Oh, and if you go the vacuum storage route you should know to let your filament cool before storing it in a vacuum bag....friggin' stuff WILL vacuum weld to itself where it touches.

Neal

Re: filament storage

I recognized that for some filaments it's recommended to dry them before printing.
According to your experience, is it still necessary to dry filament if it was stored in a sealed bag/box with active dessicant?

That depends on whether it was dry before sealing it into the bag/box. If it was already (sufficiently) dry before storing in a sealed container, then it should be good to go.

Can the [desiccant] dry filament that has absorbed some moisture?

According to the experts, no.
First, it’s important to dispel a common myth. You cannot effectively dry filament out by storing it in an airtight container with desiccant. You can keep filament dry this way, but in order to properly and thoroughly dry it once it has been saturated, you need to actively dry it.

Beat Moisture Before It Kills Your 3D Printing Filament

See Also:

Re: filament storage

Since similar questions come up quite often, does anyone know of a site/article, etc. that compares/rates the hygroscopic properties of filament by plastic type? ....

You haven't seen this comparison because it doesn't really make sense to make such a thing.
....
I hope it does make sense.

First it doesn't make sense, then you hope it does... 😮 😀 😆 (Just kidding!)

But seriously, I respectfully disagree; perhaps we're not on the same page... (?)

For example, spoze we've got 1 spool each of PLA, PETG, ABS, PC, TPE, and Nylon--all pre-dried and sealed with desiccants. Assuming a climate-controlled environment, pop the seals, and stack the spools ready to print. How fast/soon will each absorb enough moisture so as to ruin printing? 1 day? 2 days? 3 days, a week? Longer? Nylon will absorb much faster than PLA (which may be OK for quite a while--my Prusa Silver has been on the kitchen table for well over a month with no appreciable moisture issues). I don't know where the other polymers fall, but I think some generalizations could be made, and those could be helpful versus repeating others' experiences/print failures/ordeals. (IOW, learning the hard way... 😡 )

Of course there are countless variables--absorption rates may vary with lower vs. higher RH, temp, etc.
But given some average climate-control, like 50% RH and 68°F/20°C ambient/room temperature (material properties are very often qualified such) I think such comparisons could be helpful, especially if/when troubleshooting a bad print or planning ahead.

I just thought some kind of general reference could/would be handy rather than having to dig up & review umpteen material info sheets... especially for us inexperienced noobenheimers/tyros. :geek:

Re: filament storage

My rule of thumb is if the "snap, crackle, and pop" is not too bad, the wisps and flags on the lee side of the print aren't too bad, the nozzle is not clogging, and the surface of the print is okay then keep melting plastic.

Neal

Re: filament storage

Can the [desiccant] dry filament that has absorbed some moisture?

According to the experts, no.
First, it’s important to dispel a common myth. You cannot effectively dry filament out by storing it in an airtight container with desiccant. You can keep filament dry this way, but in order to properly and thoroughly dry it once it has been saturated, you need to actively dry it.

Hi Rufus!
Thanks for that clear statement - I suspected it but it's good to get the confirmation.
That said, I did experience a significant improvement with some PETG that I had stored in an non-sealed box for months.
It showed moisture symptoms (oozing with bubbles and crackling sounds, stringing) and was nearly perfect after storing it in a ziplock bag with a fresh 250g silica gel pack for a few days.

But I guess I'll be double and triple careful with nylon and the likes...

Cheers! Georg

Re: filament storage

I use sealable pet food containers for some rolls and large ziplock bags for others. I've checked both methods with a humidity monitor in and out of the bag / container and they seem to perform about the same.

With either bags or containers I'm maintaining an internal humidity level of about 16% (50ish% ambient humidity) with one of these units in the container or bag: https://www.amazon.com/Eva-Dry-Improved-333-Renewable-Dehumidifier/dp/B000H0XFCS/ref=sr_1_5/131-6267466-9262114?ie=UTF8&qid=1536885125&sr=8-5&keywords=dehumidifier+eva-dry&dpID=51w1SKjdCnL&preST=_SX300_QL70_&dpSrc=srch

With desiccant bags and the same bags and containers in the same room I maintain about 20-21%...not sure if that's really a significant difference with regard to effects on the filament.

For PETG that's been sitting more than a few weeks I actively dry it before use (seems to print best this way). For nylon I actively dry it a LOT before every use (seems necessary to get best print quality). With PLA I haven't seen much of a difference so I don't bother drying it anymore.

HTH

Re: filament storage

I put my filament (unopened and opened - plenty of room) in a Ziploc 60qt Weather Shield Clear Storage Box, $12 at Target. I use a Eva Dry Renewable Mini Dehumidifier to keep it dry in the box, $20 at target. The box has a seal on it, to keep the moisture out.

Works well.

Re: filament storage

I put my filament (unopened and opened - plenty of room) in a Ziploc 60qt Weather Shield Clear Storage Box, $12 at Target. I use a Eva Dry Renewable Mini Dehumidifier to keep it dry in the box, $20 at target. The box has a seal on it, to keep the moisture out.

Works well.

That is a good option.