3D Printing Materials: Which One Should You Use?

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3D printing has seen an amazing surge in popularity over the last couple of years, with desktop 3D printers making the technology more affordable and accessible for casual hobbyists. This has resulted in some creative developments and innovations in the technology, including the materials that are used for 3D printing.

Nowadays, there are literally hundreds of 3D printing filament products available in the market. With such a wide choice, it can be a little overwhelming for the budding hobbyist. Don’t worry we’ve got you – in this article, we go over the most common filaments, their respective strengths and drawbacks, and help you decide which filament you should go for.

Acetonitrile Butadiene Styrene (ABS)

ABS is a widely used material not just in 3D printing, but in many other industries. Among others, ABS has been used to manufacture sewage pipes, electrical components, toys, and automobile parts. ABS is notably a durable material, with good heat and chemical resistance and a slight flexibility.

The popularity of ABS as a material for 3D printing is a testament to how easy it is to work with. The printing temperature of ABS is in the high end – about 210 to 250 °C. The high printing temperature does pose a small challenge, as rapid cooling of the print may lead to poor layer adhesion, warping, or shrinking. To avoid this, you will have to use a heated printing bed. It is also recommended to use an enclosure to promote the slow cooling down of your print.

Finishing an ABS print is also quite easy. Rough edges can be sanded, and all surfaces can be polished with acetone to get a smooth sheen. Separate ABS prints can be put together using ABS glue.

The major drawbacks of ABS stem from its chemical composition. Printing using ABS produces noxious and toxic fumes, for which you will have to provide some sort of ventilation system. The degradation of ABS can result in the release of hazardous components such as butadiene and acrylonitrile, both of which are considered carcinogenic compounds. For this reason, it is not recommended to use ABS to print objects meant to stored food or drink.

ABS is a petroleum-derived material, which means that it is not a biodegradable plastic. Although it may be recycled, it is safe to say that the 3D printing hobby has likely produced a lot of ABS scrap that still contribute to solid waste.

Polylactic Acid (PLA)

Together with ABS, PLA constitutes for a large majority of the materials used for 3D printing. Its common applications include food packaging, medical implants, hygiene products, and furniture. It is generally a tough material, but is not as flexible as ABS.

PLA prints at a lower temperature of about 160 C and does not require a heated printing bed. It is not as prone to warping or shrinkage, and actually benefits from using a cooling fan while printing. It also does not emit harmful fumes during printing, so you should not have issues printing with PLA in your house. Overall, PLA is a very easy material to work with, more so than ABS.

The non-toxic nature of PLA is probably the biggest reason for its popularity. Unlike ABS, PLA breaks down into relatively benign lactic acid. PLA is so safe that is the material used for medical suturing that is essentially absorbed into the human body. Owing to its originating from renewable resources, PLA is also a 100% biodegradable material.

Nowadays, PLA is so popular that you can find a good selection variants and other PLA-based specialty filaments. Some of the most interesting ones include glow in the dark PLA filaments, and unique materials such as wood or carbon fiber filaments.

Nylon

Nylon is a very common and widely-used synthetic copolymer, known for its versatile applications and superior durability. Despite its strength, it is a very lightweight material, making it perfect for manufacturing ropes, tents, and parachutes. It has good elasticity, resistance to chemicals, and protection against abrasion.

In the field of 3D printing, nylon is a favorite choice for objects that need to be durable and able to withstand normal wear and tear. However, not all printers are equipped to print using nylon, as it prints at a very high temperature of 260 to 280 C. It is also quite prone to warping, so you may need to use a heated bed with an enclosure.

Nylon is an extremely hygroscopic material, so you will need to exercise care during its storage and use to minimize its moisture absorption. Printing with a filament that has not been sufficiently dried will lead to prints that are weaker and have visible cavities and air bubbles.

PVA

Polyvinyl alcohol (PVA) is a long chain polymer primarily used in 3D printing due to its property of being completely soluble in water. This property has given way to the popularity of PVA as an environment-friendly packaging solution.

You might ask, how is this solubility useful? There may be certain designs, such as those that include overhanging features, that will require integration of support structures. This comes as a consequence of the additive technology of our particular 3D printing technology. The solubility in water of PVA makes it an excellent choice for support material, as the final print can be merely soaked in water to remove the support structures. PVA breaks down in water into its vinyl alcohol monomers, making it completely biodegradable.

PVA is especially as a support material printed in tandem with PLA. PVA and PLA have similar printing temperatures, ensuring good layer adhesion and little or no warping. As with PLA, a heated printing bed is not necessary with PVA. A 3D printer model with dual extrusions will be needed if you intend to print a design which incorporates both PVA and PLA.

HIPS

We mentioned above that PVA works best with PLA. How about when you have to work with ABS? This is where high-impact polystyrene (HIPS) comes in. HIPS is a graft copolymer that has an excellent mix of rigidity, toughness, and flexibility. It is an easily manufactures, readily moldable material that has been used to create computer housings, automotive instrument panels, toys, and cups for drinks,

In contrast to the water solubility of PVA, HIPS requires a limonene solvent to dissolve. Limonene is a fairly common chemical compound so this should not pose much of a problem. HIPS prints at a temperature range of 230 to 240 C, making it the perfect support material for prints made with ABS. As with ABS, a heated printing bed with a temperature of 90 to 110 C is recommended when working with HIPS. To remove the support structures in your final print, it needs to be submerged in limonene for at least 24 hours.

PETG

You may have heard of Polyethylene Terephthalate (PET). It is one of the most common plastics in the world today and is quite ubiquitous as a material for food containers and water bottles. In 3D printing, a glycol-modified version of PET, or PETG, is used as a common filament material. The addition of glycol to standard PET makes it more durable and less brittle. PETG has been used to manufacture food containers, electronic devices, credit cards, medical tools, and prosthetic devices.

PETG has often been described as having a combination of the best properties of ABS and PLA. They have the superior durability and temperature resistance of ABS, while being almost as easy to work with as PLA. Although it also prints at high temperatures of 220 to 245 C, it is less prone to shrinking or warping and shows excellent layer adhesion.

A major drawback in using PETG is the difficulty in finding the most optimal settings for your printer to maximize the benefits of PETG. It requires very particular conditions, and a beginner might have to go through several trial and error runs to get the desired results.

Although prints made using PETG are generally very durable, they can be weakened by UV light. This means that PETG is not appropriate for printing objects that will undergo constant outdoor exposure, such as street signs or external house fixtures.

Flexible Filaments

Sometimes the durability and rigidity of plastics just does not cut it. Flexible filaments, such as those made from Thermoplastic Elastomer (TPE), are made from a blend of plastic of rubber to produce a material that combines the elasticity and flexibility of rubber with the workability and versatility of plastic.

Flexible filaments are notoriously difficult to work with, as they tend to deform inside the extruder assembly. For this reason, it is often recommended to use only Direct Extruders when working with flexible filaments, instead of Bowden extruders. Direct Extruders are placed directly above the hot end, leaving little room for the flexible filament to deform. Failure to set the printer at the optimal settings for flexible filaments may lead to a messy print full of strings and bobs.

Most flexible filaments print well at high temperatures of about 220 to 250 C. You will probably need to set a deliberately low printing speed to avoid deformation of the filament.

Admittedly, flexible filaments are niche products that serve the need for an extremely flexible filament material. They are quite challenging to work with, as you will need to fine tune your 3D printer’s settings with regards to printing temperature, printing speed, and retraction. You are also going to need a lot of patience, as printing with flexible filaments will likely be a very slow and long process.

Specialty Filaments

Going beyond the realm of standard filaments, specialty filaments are composed mostly of a PLA matrix infused with a variety of solid powder. This technique has given rice to more than a dozen specialty filaments, from wood to carbon fiber. Being PLA-based, these specialty filaments merely simulate the look of its powder material. For instance, a print made from wood filament may look like wood but may not have the same level of strength and durability.

Printing using PLA-based specialty filaments is very similar to printing with basic PLA. The printing temperature, speed, and retraction settings used in standard PLA can also be used to get good results with PLA-based specialty filaments. However, the presence of solid particles in the filament can make handling them quite a challenge. The filaments can be very brittle so you will have to make sure that the filament path from the spool to the extruder are free from sharp turns.

Another problem posed by specialty filaments is the fact that they lead to premature wearing down of the nozzle in the hot end of your printer. This is especially true for the standard brass nozzles that usually come with desktop 3D printers. To avoid this problem, you are going to have to invest in a more durable nozzle, such as one made from stainless steel.

The challenges of using specialty filaments are tempered by the fact that prints made from them have really amazing aesthetics. If you have ever wanted to create custom wooden figure and did not want to bother with complicated woodworking, then there are several PLA-based wood filaments that you can use. You can even make your own copper or stainless steel prints, glow in the dark prints, or prints that can conduct electricity. Specialty filaments are a little expensive, but they make unique prints that no other filament product can.

Conclusions

FilamentProsCons
ABS– Cheap, widely available

– Durable and flexible

– Good heat resistance

– Produces harmful fumes while printing

– Requires high temperature to print

– Prone to shrinking or warping

– Petroleum-derived and not biodegradable

– Produces harmful compounds upon breakdown

PLA– Cheap, widely available

– Fairly durable

– Not prone to shrinking or warping

– Plant-derived and 100% biodegradable

– Does not release harmful compounds when broken down

– Poor heat resistance

– Not as durable as ABS

Nylon– Very durable

– Excellent impact resistance

– Prone to shrinking or warping

– Requires high temperature to print

– May need special handling to avoid moisture absorption

PVA– Perfect support material for PLA prints

– Readily dissolves in water

– Not recommended as a stand-alone filament
HIPS– Perfect support material for ABS

– Readily dissolves in limonene

– Not recommended as a stand-alone filament
PETG– Combines durability and heat resistance with ease of use– Getting the right printer settings can be quite challenging

– Requires high temperature to print

Flexible Filaments– Excellent, rubber-like flexibility– Prone to deforming inside the extruder assembly

– Generally not recommended to be used with Bowden extruders

Specialty Filaments– Superior aesthetics

– Some filaments may have unique capabilities (electrically conductive, glow in the dark, etc.)

– Very brittle filament material

– Very abrasive to standard brass nozzles

The choice of filament material depends on a lot of factors: what kind of project you’re working on, how it is going to be used, your budget, and your level of experience. If you’re still relatively new to 3D printing, we suggest sticking to the big two: ABS and PLA. As you progress, you can start taking on the more challenging materials, such as PETG or specialty filaments.

The field of 3D printing is ever growing and evolving, and there will probably be more types of filament materials in our future. We are personally very excited for what the future holds for this technology, and we hope that you can tag along in this journey.