I got some PETG and it came WET. Like I’m surprised there wasn’t water in it wet. How do I dry it out without a dehydrater or an oven?? People are really suggesting an oven in this economy lmao
I know about the airtight box and dessicant method but that will take a few days and in all honesty I’m impatient. It’s on a cardboard spool if that matters since I don’t want a fire hazard. All the suggestions I’ve seen don’t really seem to be great as they’re all “use a filament dryer or a box”
Sorry if the answer is obvious, Google really doesn’t want me to know the tested methods lol
Edit: apologies, I have an A1 mini. Probably should have mentioned that, agh.
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You have your answer 
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I wish, they’re pretty expensive considering I got an AMS with my printer and it seems like a frivolous purchase if I can just use a box of dessicant, my power bill is probably already quite high lol
box with dessicant is to keep it dry, it won’t do the drying…
i have a sunlu s2 which was pretty cheap in a promotion, will eventually get the s4, as it’s boring to dry each one individually, but that’s what you need to do if you’re on a budget
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They’re still pretty expensive, I’m not looking to spend more than £20
Surely that’s not the only way so I’ll just keep looking for other options until I can afford it I guess
it’s definitely a worthwhile small investment, wet filament prints poorly, so you’ll be wasting rolls of filament and wear and tear on the machine with little to show for it, so i think that is more expensive than an initial spend
for a diy i’ve heard of people sticking them in an oven, i wouldn’t do it myself though, you can’t really properly control the temperature, so it can become a solid 1kg piece of filament 
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You can dry with the print bed, look at the official wiki guide on it:
I would still suggest a proper filament drier but this works in a pinch.
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Ah that’s a good price but it’s not that same price on the UK site : (
I’ll save up for it I suppose and just not use my PETG until then, shame because I really wanted to print a dummy 13 and the joints won’t hold up in PLA
Awh that could have been perfect but I have an A1 mini! Thanks for sending it though
You don’t say what kind of printer you have (that I saw - but edit - now you did 
) but @Lenyo is right - with a heated bed you can dry filament in its cardboard shipping box.
You might want to get a cheap hygrometer to monitor humidity because that’s very important to drying and most drying methods are limited by ambient humidity.
Filament really doesn’t dry well in an AMS or any container with desiccant at room temperature. The water sticks too hard to the filament and needs heat to get it to let go and be removed. Some water will leave it at room temperature but it’s very slow and won’t dry very much.
It’s hard for me to recommend drying in a kitchen oven. First if it’s gas, that creates water as a combustion byproduct and gas ovens are humid. You’re starting with a disadvantage with a gas oven. Electrics don’t have that issue but plastics can have volatile contaminants in them and in any oven they may stick around to contaminate food.
PETG HF is problematic for water. Unfortunately if you’re having water issues with it you’ll need to up your drying and storage game. Good luck!
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Thanks, and thanks everyone else. I guess I’ll just have to be more careful with who I buy from and how I store PETG. I’ll make sure to get a dryer when I get a good dry storage setup!
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And there’s the rub - folks have had water issues with just about all vendors’ filaments.
It’s actually pretty easy to measure filament water content indirectly. Just put a spool in a thick ziplock bag or a sealable impervious container with a hygrometer and seal it up. No desiccant - that will ruin the measurement. Let it sit 10-12 hours and read the hygrometer. I use those same hygrometers as you used in the AMS and dried filament pulls them to 10% (as low as they can read) in pretty short order.
If you put fresh desiccant in with filament, like your AMS reading, it can be low humidity but the filament itself may still be holding water.
Then you need to seriously reevaluate whether this hobby is right for you. It’s an expensive hobby, and there are no shortcuts. Desiccant alone won’t do the job; it only absorbs moisture from the surrounding air. To dry filament, heat must be applied to release the water molecules. The laws of physics are impartial—they apply to everyone equally.
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Just from a theoretical standpoint this doesn’t make sense as a measurement technique. The nitrogen in the air and the plastic in the filament have a different attractive force to moisture. They will reach an equilibrium that is related to the moisture in the plastic, but other than “went lower” or “stayed the same” you can’t attach any significance to the number.
As a thought experiment, imagine using your technique to measure how much water is in silica desiccant itself. Sure, exhausted gel will read higher, and dried gel will read lower, but other than that you can’t ascribe any meaning to the numbers.
It actually does make sense. There are graphs for various hygroscopic materials that relate moisture content and equilibrium humidity. The relationship is indeed defined by various characteristics of the material and every moisture content has a corresponding humidity and no duplicates.
That means we don’t have to know the actual moisture content. We can just know the equilibrium humidity to know where we are on the moisture content / humidity curve - even if we don’t know the curve or moisture content. What is important is that relationship is defined by the physical properties of the material and doesn’t change.
What we do is just use the equilibrium humidity instead of moisture content. If I test the equilibrium content of a spool and it’s 30% RH and doesn’t print well, but it does print ok when I dry to 20% RH in the test method, then I know spools showing 30% and above will cause problems and spools 20% and below should be fine. Through experience we can narrow up those ranges to know what to expect from 25% RH test results.
But I don’t think many or any are doing this. Nobody believes it works I guess. I am not generating useful data now either. I dry my filament to where it pegs the hygrometers low and don’t see moisture effects so am gaining no experience where the dividing lines are because my filament isn’t wet to marginal any more.
I believe it “works” in the sense that higher moisture in the plastic results in a higher reading on the hygrometer, I just don’t think it’s a useful technique. You’d need to have equilibrium points for each material (PLA, PETG, Nylon, etc) and control for temperature carefully (10c->20c is 2x more moisture capacity in air). Too many variables and hand-wavy numbers to interpret.
That’s funny because it worked fine for me before I decided it was better to just dry to a point far beyond the transitions and not worry with it.
For me, it’s not useful any longer because my filament is more dry than it needs to be to not show moisture effects. For others with stringing, lifting, and other moisture issues it’s a way to diagnose why. The very few who have tried it and reported back found their humidity levels were fairly high.
But as a true diagnostic the issue isn’t that it’s hand-wavy. It’s really not. It’s that people don’t seem to understand it or trust it and the lack of information on where the issues appear makes it less useful. But it’s still a good diagnostic and could explain why some have issues. (And has.)
Time to trot this out and just drop moisture issues. Few seem to care.
