Why we need dry filaments
Filaments are an indispensable part in 3D printing world, and moisture absorption is an invisible killer here.
Learning what it is and impact on printing ,then we can prevent and reduce our losses more effectively in our lives. Just don't mess project up!
- What is hygroscopicity
Have you ever used old filament or wet materials for printing? If so, you may experience some print quality issues.
This is most likely due to hygroscopicity, the filament has absorbed water in the air. Most filaments naturally absorb more moisture than other filaments. This means when there is moisture (humidity) in the air, the filaments will naturally absorb it.
Although it is difficult to detect in advance, moisture absorption is a factor that adversely affects the quality of 3D printing. The moisture in the printed material cannot be found by ourselves, but we can find it happening when heated on the hot end of the 3D printer. Essentially, as the filament melts, the water boils, which causes foaming.
- What bad impact on printing
When the hygroscopic material absorbs moisture, printing with "wet" filaments can cause a lot of printing errors, including the following: air bubbles in the printing layer; clog in the extruder; poor adhansion attached to bed ; extra crowding out problems.
If you look at the picture above, you can see the difference between printing with wet (left) and dry (right).
When printing with wet filament, the first sign you will notice. The hissing suddenly appears ,it sound comes from the hot end, usually accompanied by visible steam out of the nozzle. This is because the water evaporated in the filaments when the wire reaches the hot end. This may not trouble you a lot, but we think it is destroying your extruder components .
When the moisture inside evaporates, it will interrupt the normal extrusion performance of the filament. This often cause in under-extrusion or "gaps" in the extrusion. This means that small gaps or holes are printed in the layer.
This will be some consequences happen. Since the printing of each layer is incomplete, the adhesion between layers tends to decrease. This makes the finishment weak in terms of mechanical strength and there is a pit-marked surface. Although the latter can still be remedied by sanding , weak 3D printing will inevitably collapse faster than expected.
Keeping the filament dry is not only should be done before printing, but also important when storing the wire. Wires filled with moisture will become brittle after a few months.
This is simply because the presence of water promotes the hydrolysis process. When water reacts with polymers, they break down into smaller chains, reducing their strength and elasticity. If unattended, the wet filament will eventually become much brittle that it will break down and unusable.
- What materials need to dry
Before discussing which material need to dry, you should know that all materials are hygroscopic and which most affacted.
In other words, there are many types of moisture-absorbing materials. It is a good idea to store properly and dry all filaments if necessary, but please note that the following materials are most likely to get wet quickly: ABS; Nylon; Polycarbonate (PC); PETG; PVA; TPU.
Although there is no material that is completely non-hygroscopic, some are not moisture at easily way. Compared with the above materials, the following materials are better on anti-hygroscopic: PLA & PP.
|No.||Materials||Dryer Temp||Drying Time|
|1||PLA||55°C (131°F)||> 3h|
|2||ABS||65°C (149°F)||> 3h|
|3||PETG||55°C (131°F)||> 2h|
|4||Nylon||70°C (158°F)||> 12h|
|6||PVA||55°C (113°F)||> 8h|
|7||TPU/TPE||55°C (131°F)||> 4h|
|8||ASA||60°C (140°F)||> 4h|
|9||PP||55°C (131°F)||> 6h|
|11||PC||70°C (158°F)||> 6h|
These recommendations above are made under the following conditions.
* Ambient RH: 50% * Ambient Temp: 20°C (68°F) * 1kg (2 lbs) filament spool
Actual filament drying times will vary due to different filament additives, different initial water content levels in filaments and ambient temperature and humidity.
Quick tips summary
The importance of dry 3D printing filament is too often overlooked! If you have problems printing a material, make sure it’s sufficiently dry!
Vacuum drying works, though it’s not as efficient and effective as drying with heat.
Adding dessicant to the vacuum chamber helps a little.
Weigh your material regularly to determine when drying is finished if you’re in doubt.
SUNLU dryer it's a solution and AW-3D Printing will help on it improving in near future!
Our friends do helps a lot,as link creative tube, thank you all our friends!