I’m using AMS PRO2, which recommend us to dry PLA for 8 hours straight!
It sounds sooooo long.
How much does it cost for electricity and everytime I have to print, do I always need to dry filament like this way???
Can’t you dry filament and print simultaneously?
You dont have to dry it unless its wet and exhibiting some brittleness (PLA) or stringing while printing. Its much easier to store it properly, I use those big clear bin from IKEA with a box of desiccant in each one. Also it really depends on the humidity in your area. Up here in Toronto its pretty dry so even if I dont store PLA in those bins, it takes a very long time it to get wet and spoil.
With some engineering filaments like PA/PPA/PPS its is a requirement to dry before printing as they are very hygroscopic, I use vacuum bags to store those.
Thanks so much.
What if it’s 45-55% at inside of house, and keeping filaments in AMS PRO2?
Actually, I see a lots stringing these days.
Am I supposed to use AMS PRO2’s drying function before printing?
You are supposed to use it when you see problems appearing due to moisture. Honestly its nice the AMS 2 has built in drying function but as it can only be used while not printing (unless you have multiple AMS units and the power supply) I am not a big fan of that feature. Its much more convenient to use a stand alone dryer that does not take your printer out of commission. A good one can be purchased very cheap now days.
Thanks!!!
Do you have any recommendationfor external dryer??
You want three things in a dryer:
I use a FixDry NT2 as I purchased it very cheap and I wanted a small unit due to limited space but I dont think they are available anymore, NT1 (single and dual) are sold on aliexpress. As long as it has the above features any brand/model will do, its a simple heating device. You might want to buy a two or four spool unit if you have the space/budget/need for it. Creality Space Pi and Sunlu has some nice models, but they are not cheap.
https://a.aliexpress.com/_mslDRoj
https://a.aliexpress.com/_mNqrYLd
@maxximit is correct. It may not need dried. Unless youre in a hurry, it wont hurt. I dry pla for 12 hours personally. Kind of a measure twice cut once idea. Or I guess dry good print once.
I have similar humidity levels here and honestly I never dry PLA.
It’s a different story with PETG and the more technical materials.
I even store PLA in the paper boxes it came in without any bags. As I heard you can overdry PLA and it becomes brittle then not due to moisture but due to too much longtime heat, which changes the chemical structure. No first hand experience though, as I never dry it 
I’m very careful though to protect PLA from UV light, e.g. sun because that can badly deteriorate PLA. Some brands (or colors?) seem to be resilient while others very susceptible.
So if you stay with PLA for now, I would delay the decision for a dedicated dryer until you really need it and know what you will be printing.
For PETG, 70°C is fine. For PC and Nylon you rather want higher than that. If you have an air fryer that could also be the perfect filament dryer.
I use either the heatbed or our air fryer but I’m heavily eyeing the AMS HT because it ticks many boxes for me.
In my opinion, there’s usually no need to dry PLA or PETG filament. I’ve been printing since 2020, and I’ve only had one issue with moisture—specifically with a spool of PETG that had been sitting out of its packaging for over a year. You could already tell visually that it had absorbed a lot of moisture.
I ended up using my wife’s food dehydrator (she wasn’t exactly thrilled to find filament drying in there instead of apples 
—but that’s another story). After drying, the filament printed just fine.
ASA and TPU, however, are a different story. I take much more care with those—I always store them with silica gel beads in airtight bags or containers. But of course, that’s just based on my personal experience.
The idea is to dry it before first use or if it has been stored for a long time - not every time you use it. This is because it can’t be guaranteed to be “dry” out of the packet/storage.
Local conditions and storage method will affect how long filament can be stored or left without needing to be dried. My usual approach to storage is vacuum bags with a pack of colour changing dessicant as this gives and indication of how much moisture has gotten in.
Also remember that drying is the means, not the end. As long as the print is good then it’s fine. Filaments don’t have to be bone dry to print well.
It may depend on the climate, but I haven’t had to dry any PLA or PETG. I store PLA in the open on a rack. I also have no desiccants inside the AMS which shows a 30% humidity at the moment.
Ive shot steam from the nozzle many times before I learned (Do a long manual purge close to the front of the bed and watch closely). Bambu pla is usually good to go, but I still dry it when I open it. May aswell make the best possible print, if you have the time to wait. It also plays a role in overall strength of the finished part and how much it will shrink and warp over time(PLA). If you havnt noticed, some pla parts slowly shrink
It’s not because of being or not PLA, it’s because of ADDITIVES.
Shiney, or foamy filaments require to be dried, because of their additives. Otherwise you’re going to have a nightmare…
Additives may cause issues, however moisture is a big factor; it turns to steam at 3D printing temperatures, and there’s a big difference between laying down a clean track of plastic vs. mixed steam bubbles and plastic coming out of the extruder nozzle, and drooling when you didn’t want plastic coming out. And it takes a LOT of energy to boil water; that’s going to suck heat out of the hot end. Consider what you might do to quickly cool off something hot: dunk it in water or spray water on it.
Filament is extruded through a water bath during manufacturing (speaking of quickly cooling something off). I use filament from many sources, and I’ve had some of mine for quite a while. Apparently some batches from some manufacturers – or, permeability in the bags and shipping or storage in humid conditions; this plastic may be coming from halfway around the world in a cargo container in or on top of an ocean-going vessel – results in moisture in the filament.
Rather than risk print failure, I just formed the habit of drying my filament in a stand-alone dryer.
Agreed that dryers should be settable to at least 50, 60, or 70C (PLA, PETG, Nylon).
Preferably single-button-push select of a long drying time.
We’ve NEVER had a problem with PLA. The only ones that can be troublesome if not dried is the translucent, and to a lesser degree the silk variants (the silk is more susceptible to specific settings which are more likely to be the cause of any issues), but the basic and matte, we’ve had so little problems that we even stopped placing it in sealed bags. We have far too many reels to use tubs or containers, we just don’t have the space. Just wrapping the reels in a layer of cling film instead unless it’s a colour we only use occasionally has been fine. We’re UK based, which isn’t exactly the warmest, driest place and our humidity reading outside the printer is around 35%.
Do be aware that we do use the dessicant holders placed in the middle of every reel, so there’s something there to absorb any moisture all the time. If you’re having problems with stringing try increasing the nozzle temp by 5 degrees or so.
It’s important to remember that everyone’s humidity environment is going to be different than others.
Those in dry environments can certainly give advice to others but it likely won’t be useful or could even be misleading for those in more humid environments.
Those in humid environments will have to do more to dry and be more careful with filament storage than those in dry environments.
Anyone having issues with filament moisture should measure ambient humidity to see where they are on the spectrum. My ambient humidity is around 40% generally and I have to dry and store carefully to keep water from affecting my prints.
Anyone saying “all you have to do is…” without stating their own conditions and knowing if others are in comparable environments could be giving misleading advice. These answers need to be qualified and conditions specified. This is obvious by inspection of the well-meaning answers given — they mostly all contradict each other. They are likely good and valid for the person giving the advice, but can be totally wrong for others in different environments. It matters.
Those asking for help need to understand there are big ranges of ambient humidity. Know your own environment and ask yourself if the helper has stated their own environment where you can tell if the advice is appropriate for you or not. You can still pick up tricks and tips, but without environment details you could be wasting time and money.
Also, plastic bags tend to be terrible for long-term filament storage in humid environments. Water diffuses through the walls. Without desiccant in the bag to scavenge water and a hygrometer or indicating desiccant to know how much water has leaked in, it can be a false sense of security. This includes brand new filament in the factory bag with desiccant. It can be too wet to print well and still need to be dried to print properly.
Well said.
My home sits at around 25 to 35 percent humidity all year around and the AMSs usually sit around 5 to 15 percent. If I based my advice off of my experience, I would tell people to keep their PLA and PETG out on a shelf and to not worry about some silly cereal boxes or complicated drying setups. The only filaments that I keep stored are nylon, tpu, and pc, but I also do not dry them before printing most of the time.
The only “universal” advice is to always use desiccant (it is cheap enough that you might as well) and get a system to regulate the humidity in your home. I spent an extra 500 dollars to get a good dehumidifier built into my AC when I got it replaced a few years ago, and I am glad I did that instead of fussing around with humidity issues.
Side note: 5 gallon bucks are my go to. Pick them up for $3 at almost any hardware store and I can get 6 kg of filament in each one.
I live in FL and the printer is in the garage. Humidity hasn’t been a huge issue for me so far, except for older filaments. I bought a cheap toaster oven to dry petg and abs before printing with it. I don’t worry about PLA. I also keep desiccant pods in my AMS 2 Pro and HT. Humidity in the garage is around 40-55% this time of year. The ams units read around 15 to 25%. I do have to recharge the beads every week or so. But again, pop em in the toaster oven at 200 for 3 hours and they are good.
I guess it depends on humidity levels and brand. I’ve never had to dry PLA, stopped doing so a long time ago and I’ve had no real issues other than with translucent. I have had to dry PETG frequently though, in particular a few reels of Elegoo that I bought but the Bambu PETG-HF has been fine, when you can get it. I’m in NW England where it rains a lot. I store in individual bags, I use the blue resealable ones for PLA and single use ones that I seal with a vacuum sealer for PETG. I also add a desiccant “tube” to the core of each reel. Seems to work fine for everything except the Elegoo which has been a pain, will be glad when it’s gone.
for pla just print it and only worry about drying if it goes weird
British people always say their country is rainy but it is not really.
