What Problems Can Wet PETG Cause?
The printing process with a wet filament of any type can cause all sorts of problems. The surface quality of your final product will undoubtedly suffer if you use wet PETG filament. Wet filament can cause the individual layers of the print to have trouble adhering to each other properly.
This can cause the strength of the bonds between each layer to be compromised, ultimately causing your print to be much weaker and more brittle than it should be.
How Do You Know If Your PETG Is Wet?
It’s hard to tell that your PETG filament is wet by simply looking at it, and you might not notice that your print’s layers are not adhering properly until your print is nearly complete. However, there is one indicator that is an obvious sign that your PETG is wet.
If you can hear any sort of popping or crackling sound coming from your extractor, that most likely means that your PETG filament is wet. Those crackling noises occur when water in the PETG filaments dry is heated to the point of evaporation and pops while the PETG is melting. Just like a wood-fueled fire, crackling means that the material being heated is wet.
How To Dry PETG In An Oven
If your PETG gets wet, there is no need to panic. There’s no need to go out and buy new PETG filament and no need for the use of any fancy and expensive equipment. All you need to completely dry out your PETG is the oven thermometer in your kitchen.
All you need to do is preheat your oven to 150 degrees Fahrenheit, put your PETG in, and wait around 4 to 6 hours. This will be plenty of time to dry out the filament leaving it as good as new. Just be careful not to turn the desired temperature up much higher than 150 degrees, as you may risk melting the dry filament to internal temperature, rendering it unusable.
Another thing to be cautious of when drying PETG in an oven setup is the cleanliness of your oven. You need to make sure that your oven is spotless, as stray particles of food and grease can end up on your dry filament, further reducing the quality of your PETG.
The last thing you want to do is reduce the quality of your PETG in this way when you are trying to do the exact opposite.
Additional Ways To Dry PETG Filament
Though not quite as simple and cheap as using your oven, there are other things you can use to dry PETG filament as well. The most common of which are wet filament dryers and food dehydrators.
For anyone looking for the most professional way of doing things, filament dryers like the Print Dry Pro and Sovol SH01 allow proper storage and drying of your dry PETG filament as you’re printing, making this the best long-term solution for anyone willing to shell out the extra cash.
Food Dehydrators are also great for drying filament inside, and if set around 150 degrees Fahrenheit, your filament will be dry in about the same time as it takes in the oven. However, I would only use this method if you happen to already have a food dehydrator lying around, as it makes much more sense to spend your money on the much more purpose-built specialized filament dryer instead.
How To Prevent Water and Moisture Absorption By Properly Storing Your PETG
Though there are many easy ways to dry PETG filament, the best way to approach the problem is by simply preventing your PETG from absorbing water in the first place. You can do this by ensuring that you are storing your PETG filament properly.
Since PETG filaments are hygroscopic, they do not need to physically be submerged in water for them to get absorbed. PETG absorbs moisture from the air bubbles until it is completely waterlogged, and no more water can be absorbed.
This means that people living in the more humid regions of the world will have a bit more trouble keeping their PETG filaments dry box than those who live in a specialized filament dryer area.
No matter where you live, you should, at the very least, be sure that you store your dry PETG filament spool in an enclosed container in the coolest and driest part of your home.
If you plan on purchasing any of the above-mentioned filament dryers, you will already have this step taken care of, as they also act as a dry box, absorbing moisture out of the environment where your dry PETG filament is being stored. If not, any sort of airtight container kept in a dry box part of the house will do the trick.
If you have a vacuum bag, vacuum sealing your PETG is another great option in the absence of any appropriately sized airtight containers. Humidity inside can also help to keep the moisture level in the air around where your PETG is stored much lower so that it has less opportunity to absorb moisture at all.
Silica gel beads can also be put around where your PETG is being stored to suck all the moisture out of the air before it even reaches your wet filament.
The key here is to just work with what you have. You don’t have to have the perfect filament storage setup to keep your PETG in tip-top shape. As long as you have the ability to use one or more of these drying methods in unison, you will be able to keep your PETG dry enough to where it can be used with only minimal to no strong filament drying temperature at all.
Common Mistakes When Drying PETG Filament
We all learn from our mistakes, and it's these little tweaks that can make all the difference in your 3D printing process!
1. Skipping the Preheat
It might seem like a small step, but preheating your convection oven is crucial. This ensures that the filament dries evenly and can prevent moisture absorption or any unwanted surprises.
2. Overcrowding the Oven
Just like when baking cookies, you don't want your filament to touch. Make sure to spread it out so every inch gets the love it needs to dry properly.
3. Getting Impatient
I know, waiting for 4-6 hours can feel like forever. But trust me, cutting the filament drying time short won’t do you any favors. Patience is key!
4. Neglecting Monitor Duty
Always keep an eye on your filament during the drying process. Overheating can lead to damaged filament and, ultimately, subpar prints.