Do not let moisture within the air have an effect on your filament or your 3D prints. Take an in-depth take a look at the science behind your filament and the way water within the air impacts it.
All plastics, together with 3D printing thermoplastic filaments, are polymers. Polymer science is an unlimited and complicated subject, but it surely’s pretty simple to grasp what a polymer is. A polymer is a cloth made up of a number of repeating monomers. That in all probability appears like one other language, so let’s put it by way of a cloth you’re probably conversant in – PVC.
The Fundamentals: What Is A Polymer?
PVC, which is brief for Poly (Vinyl Chloride), is a cloth made up of a number of vinyl chloride molecules joined collectively in lengthy chains. Vinyl chloride is the monomer, and there are a lot of of them, thus, ‘poly’. Straightforward sufficient, proper?
More often than not, the “P” in a cloth abbreviation stands for “Poly”. Frequent examples embody:
- PET – Polyethylene terephthalate, generally often known as Polyester
- PLA – Polylactic acid (additionally known as polylactide)
- PP – Polypropylene, or polypropene
- PE – Polyethylene
- PS – Polystyrene
- PA – Polyamide, generally often known as Nylon
PLA, PET, and Nylon – these are just some of many polymer supplies that makers can 3D print their elements with.
Now, you probably have come throughout the phrases ‘copolymer’ and/or ‘copolyester’ when filaments to your 3D printer.
A copolymer is solely a polymer made up of multiple monomer. ABS might be probably the most acquainted copolymer. It’s made up of three monomers – Acrylonitrile, Butadiene, and Styrene. Particularly, ABS is a terpolymer, as a result of it’s made of three monomers, however ‘copolymer’ covers every little thing comprised of greater than 1 monomer. Different examples can be Taulman’s line of Nylon copolymers – 618, 645, Bridge, and Alloy 910.
A copolyester is shaped when PET, aka Polyester, is modified. Copolyesters have gained recognition as 3D printing filaments not too long ago – PETG, PET+, Colorfabb XT, nVent, nGen, and T-Glase are all copolyesters.
MatterHackers’ NylonG is made out of Polyamide and strengthened with glass fibers to extend tensile power and soak up giant quantities of kinetic power.
Hydrolysis – Sounds Fancy; Is It Dangerous For My Filament?
Now that we’ve got a fundamental understanding of what a polymer is—an extended chain of monomers—it’s time to speak about water and a course of known as hydrolysis.
When monomers are joined collectively, it’s known as polymerization. Be aware that this isn’t a one-way avenue. Polymer chains can degrade and be damaged down—or depolymerize—and there are numerous ways in which this occurs. One in every of these methods is hydrolysis. Hydrolysis is when a water molecule breaks a polymer chain. All types of advanced chemistry happen when polymers hydrolyze. We’re not going to get into these particulars, however the materials properties affected when hydrolysis happens (they’re modified anytime the polymer chain size is decreased or elevated) are lack of tensile power, change of readability, and so forth.
If you extrude filament that has absorbed water, the water in/on the fabric vaporizes and creates air bubbles. This may break aside polymer chains (shortens them), weakening the fabric and creating voids within the strands of filament which weakens inter-layer adhesion. It additionally leaves an undesirable floor end.
Chances are you’ll not realize it, but it surely’s probably that you’ve got already skilled the consequences of hydrolysis in your 3D printed elements. Pictured under take a look at prints made out of Taulman Bridge nylon. The left was dried earlier than printing. The precise was not dried. These had been printed with materials from the identical spool.
The print on the left was dried earlier than printing whereas the print proper was not dried.
After drying the nylon spool in a vacuum oven earlier than printing, we produced the print on the left. Then we left that very same spool sitting out for two+ weeks earlier than printing, which resulted within the print on the precise.
The dried nylon is pretty clear. The moist nylon is sort of opaque. It is probably not clear within the picture, however the dried nylon has a easy, shiny end, whereas the moist nylon has a tough, textured end. Each objects are powerful, however the moist nylon is significantly simpler to tug aside on the layers. You may as well see that nylon tends to warp—regardless if it’s moist or dry.
That is MatterHacker Black Professional Sequence PETG. The left dice was dried earlier than printing, and the precise one was allowed to take a seat out for two+ weeks.
The left dice was dried earlier than printing, and the precise one was allowed to take a seat out for two+ weeks.
As you may see, there’s a clear distinction in floor end and texture. It’s onerous to inform within the image, however the dry dice is shiny and has a constant end from prime to backside. The moist dice is textured, with a satin-matte end. The feel is the place air bubbles left voids. Moist PETG is considerably extra brittle than dry, and the interlayer adhesion is considerably diminished.
Happily, a lot of the filaments we print with aren’t very inclined to hydrolysis at room temperature with out the presence of an acid or a base. They’re, nevertheless, very inclined to hydrolysis when heated to extrusion temperatures. Because of this we don’t have to fret as soon as a component has been correctly printed, however we do have to take steps to forestall hydrolysis when printing.
Since lots of the widespread 3D printing supplies are hygroscopic (readily soak up moisture from the air), we should take steps to each dry our filament and maintain it dry.
Nylon, polycarbonate, and copolyester filaments are all very hygroscopic and inclined to hydrolysis when printed within the presence of water. Nylon and PC can soak up sufficient water in 48 hours to damage prints.
How Do We Know If Filament Is Moist And Wants To Be Dried?
The best approach is to extrude some filament and watch it come out of the nozzle. Should you see any bubbles, hear any hissing/popping/cracking, or see steam coming off the filament, then it’s positively moist and must be dried out.
This video reveals a transparent distinction between moist and dry nylon. (This was Taulman 645 nylon)
The Best Strategy to Dry 3D Printer Filament
Though the strategies that we’ve got listed are tried and true, the best strategy to dry 3D printing filament is with the PrintDry PRO Filament Drying System. Its compact body lets you dry and retailer filament proper out of your desk or workspace, each outdoors of printing hours or throughout printing. It even comes with one vacuum-sealed container and pump for further cupboard space. We right here at MatterHackers have been utilizing the PrintDry for fairly a while and are more than happy with the outcomes.
When you have nylon, polycarbonate, TPU, TPE, or PETG and the spool has been sitting out for greater than a day or so, then you definitely probably have to dry it. PLA and ABS are additionally inclined, but it surely takes fairly a bit longer for them to soak up sufficient water to trigger main points.
How Do You Dry Filament And Preserve It Dry?
There are just a few methods to dry out filament and maintain it dry.
First, it’s necessary to dispel a typical fantasy. You can’t successfully dry filament out by storing it in an hermetic container with desiccant. You possibly can maintain filament dry this manner and it’s extremely advisable when not utilizing a spool. Nevertheless, to correctly and totally dry it as soon as it has been saturated you have to actively dry it.
Essentially the most obtainable methodology to dry your filament is to bake it in an oven. Nevertheless it’s simple to overheat your filament which might trigger off gassing from the plastic. These gasses will be poisonous, which will be harmful to inhale or have meals close to. Ovens will not be advisable for drying filament, nevertheless it nonetheless will be executed with warning. Convection ovens work very effectively as they continuously flow into sizzling air across the spool. That is basically how the uncooked resin pellets are mostly dried – sizzling air is handed over and thru the uncooked resin pellets earlier than they’re extruded.
There’s one necessary factor to know earlier than baking your filament. You need to preheat your oven and permit it to achieve the set temperature earlier than placing the filament in. Ovens work the identical approach that sizzling ends on 3D printers work – with PID temperature management – and it’s widespread for ovens to overshoot the goal temperature a bit. This doesn’t have an effect on meals, but it surely positively can damage your filament by fusing the filament and/or melting the spool that it’s on. To utterly take away any risk of by chance fusing/melting your filament throughout drying, we advocate utilizing drying methods particularly designed to take away moisture from filament just like the PrintDry.
Efficiently print hygroscopic filaments with ease through the use of a PrintDry Filament Drying System.
How To Dry 3D Printing Filament:
1) Preheat your oven to 160-180°F (or 70-80°C).
2) Place spool within the oven for 4-6 hours
3a) Take away and place it in an hermetic container, ideally with desiccant. 5-gallon buckets with hermetic lids from native {hardware} shops work very effectively for filament storage. Raw rice works as an affordable desiccant various.
3b) If utilizing a PrintDry PRO, you may alternatively feed filament out of the system’s port and on to your 3D printer for dry storage whereas printing.
Filaments with decrease glass transition temperatures (Tg) like PLA, use decrease temperatures to dry. Decrease temperatures additionally require extra time to totally dry.
That’s just about all that’s essential to dry out your filament and guarantee optimum materials efficiency and floor end. Lots of our clients usually resolve mattress adhesion points and tough floor completed elements by merely eradicating the moisture that has gathered of their filament. When you have some spools which were sitting out for some time and aren’t printing in addition to they used to, dry them out and check out once more. Possibilities they simply want a bit drying off to print like new once more.
As at all times, Comfortable Printing!
Preserve your hygroscopic filaments freed from moisture earlier than 3D printing to realize most high quality elements.
