Selecting a filament material - Microsoft Teams Tutorial

- [Woman] There are many different types of filament that can be used by a 3D printer. It can be challenging to figure out what material you want to use for a particular project. This movie covers some criteria you can use to think through which filaments are best suited to what you're trying to do. One key thing you need to worry about is how strong your material needs to be. Various days have looked at the strength of filament plastics and gotten widely variable results. Rather than give numbers with a lot of caveats we'll discuss the materials in comparison with each other. It's best to test apart made with the precise filament you plan to use right down to the color. Since different types and concentrations of pigment can affect the plastics properties. There are new formulations almost daily that combine different materials. In general, it's a good idea to keep the printer filament cool and dry and sealed up somehow. Weather seal containers or vacuum bags are best. A five gallon bucket is a good alternative. A first rule of thumb is to print in the easiest to use material you can get away with. Generally speaking, this will be PLA, which is very forgiving for most applications and can be printed on printers without a heated bed. PLA is also biodegradable in commercial composters. PLA however, will start to warp significantly in environments like a car dashboard on a summer day or a desert garden. But if you're just making a model that does not have to be very strong and you won't have it in a hot environment, PLA can be a very good way to go. PLA comes in a wide variety of colors and even in translucent forms, they're also filled PLAs, shown here along with regular PLA pieces. The ones shown here includes steel field two plain PLA pieces, and one woodfield. - [Man] Another material that's relatively easy to use is PETG which is a close relative to the plastic that water bottles are made from. PETG can handle much higher temperatures than PLA unless it requires an extruder that can handle higher temperatures than PLA. Most formulations printed a range of 240 to 260 C which is a bit too hot for printers that have a PTFE liner inside the nozzle. PETG makes very attractive and sturdy translucent prints like the one shown here. As a side note although some PETG formulations are food safe making a food safe part also requires a printer that's designed for it. - [Woman] ABS is another common material for 3D printing. But its use has become much less common. ABS is a plastic used to make many toys in consumer products. It's stronger and less brittle than PLA and can withstand higher temperatures. It also needs a nozzle that can handle temperatures in the 240 to 260 C range. ABS needs to be carefully temperature controlled during a print, and so it needs a heated bed and ideally a temperature controlled chamber. ABS will want to pull away from the print bed if the temperature is not matched carefully and can split along layer lines if cooled too rapidly. - [Man] Nylon is another strong material that's flexible when printed at a few layers thick and strong when printed in more substantial pieces. Nylon can be challenging to print since it does not like to stick to anything. A print bed made of Garelight LE shown here is recommended for printing nylon. Though some formulations may be able to print on some other surfaces, nylon tends to absorb moisture more than other filaments. If nylon filament has been sitting around somewhere damp the print can be pitted by water boiling and popping out as it prints. These bubbles of moisture can also weaken the print significantly. Nylon can be dyed after printing, using nylon fabric dyes. They're also materials mixed with chopped carbon fiber or even continuous fiber. These fibers increase the materials rigidity and may increase part strength. We'll talk about those in the movie about composites. If a print needs to be strong to withstand higher temperatures, you can also try polycarbonate. Like ABS, only more so it needs to be printed at temperatures that push the limits of consumer printers. It also tends to warp during printing unless high extruder and bed temperatures are maintained. Even higher temperature materials like PEEK and Ultem require machines specifically designed to handle the temperatures required. - [Woman] If you need to make something flexible you might consider printing in a TPE or TPU. These stand for thermoplastic elastomer and thermoplastic urethane respectively and the terms are often used interchangeably. These materials can be used to make very flexible prints. They're challenging a print because a soft filament can flex during a print and tend to jam in the extruder. It's particularly challenging for printers with Bowden tubes using 1.75 millimeter diameter filament. Elastins printed moderate temperatures, one of the better known ones is called NinjaFlex. They have moderate heat resistance. - [Man] HIPS and PVA are specialty filaments that are usually used as dissolvable support. HIPS dissolves in limonene and PVA in water. This solubility makes some unsuitable materials for many applications. PVA in particular, is notorious for turning into a sticky mess if it gets damp. Unless you have a very unusual application, it's unlikely that you would want to create a whole print in either of these filaments. - [Woman] Chemical compatibility is an issue in many applications. If you're creating prints that will be used in water or an environment where they may be exposed to other chemicals, you should check with the manufacturer of your particular filament for compatibility since formulations vary. Similarly, UV resistance varies with formulation and color significantly. You may also be able to increase the material's UV resistance with coatings applied after a print is complete. If something is going to be outdoors, heat, water absorption, and where the plastic is made brittle by UV all need to be taken into account. When strength is important, you also need to remember that the print will be a lot stronger in the plain parallel to the platform than will be across layers. This is particularly true for loads that create tension forces that want peel part layers. Finally, there have been some moves by big chemical companies to create filament versions of their industrial brands or new materials. The availability of well-known industrial plastics in the 3D printable spear may give a big boost to short run manufacturing. Now designers might be able to 3D print a prototype in the same material. They'll be used for the production part. For more about this, check out our course: 3D printing short-run production. The bottom line is this. See if you can print in PLA. If you need more thermal stability and strength try PETG next, followed by ABS, nylon or for extreme cases, polycarbonate. If you want a flexible print you most likely use the TPE or nylon. However, not all printers can print in every material. We'll explore more specialized materials elsewhere in the course.