Introduction
Polyethylene Terephthalate Glycol-modified (PETG) filament is a versatile and durable material popular in the 3D printing community for its strength, flexibility, and clarity. As a copolymer, PETG filament combines the properties of PET (Polyethylene Terephthalate), the material commonly used in water bottles, with glycol to eliminate brittleness and increase durability. This results in a filament that is not only strong and flexible but also resistant to moisture, making it an ideal choice for a wide range of applications, from functional parts to aesthetically appealing projects.
PETG stands out due to its ease of use, bridging the gap between the easy-to-print PLA and the strong, durable ABS without the significant drawbacks of either, such as the odor and warping associated with ABS or the brittleness of PLA. Its excellent layer adhesion reduces the likelihood of delamination, and its resistance to chemicals and UV light further enhance its utility in various environments. As a result, PETG is rapidly becoming a go-to filament for both hobbyists and professionals seeking a reliable, all-purpose material.
About PETG Filament
PETG’s unique composition offers a sweet spot of properties: it possesses a high strength comparable to ABS, without the noxious fumes during printing, and it has a higher flexibility and heat resistance than PLA, making it more versatile. Additionally, PETG is hygroscopic, meaning it absorbs moisture from the air; therefore, proper storage is crucial to maintain its printing quality.
One of the most appealing aspects of PETG is its translucency and glossy finish, which can be advantageous for creating visually striking objects. However, this can also be a double-edged sword, as PETG prints might show layer lines more prominently than other materials. Despite this, its resistance to impact and temperature makes PETG an excellent candidate for both outdoor applications and mechanical parts.
Possible Applications of PETG Filament
Outdoor and Automotive Components
PETG’s UV and weather resistance offer durability for outdoor fixtures or automotive parts exposed to the elements.
Enclosures for Electronics
The material’s resistance to chemicals and moisture, coupled with good thermal resistance, make it suitable for protective casings for electronic devices.
Medical Devices and Prototypes
PETG is a prime choice for prototyping medical devices due to its strength, flexibility, and the fact that certain grades of PETG can be sterilized, adhering to hygienic standards.
Household Items
Its safety for food contact (when using food-safe filament and printer settings) and dishwasher resistance make PETG ideal for kitchen gadgets, containers, and other household items.
Pros and Cons of PETG Filament
Pros: PETG combines durability with ease of printing, offering a strong material suitable for a wide range of applications. It provides excellent layer adhesion, reducing warping and shrinkage, and exhibits great chemical resistance. Unlike ABS, PETG doesn’t require a heated bed or enclosed chamber, although using a heated bed can improve first-layer adhesion. Moreover, PETG is less prone to absorbing moisture compared to PLA, enhancing its shelf life and usability.
Cons: Despite its benefits, PETG can be sticky during printing, which might lead to stringing or blobbing, requiring fine-tuned retraction settings. Its shiny surface can also highlight imperfections, demanding higher attention to detail in print settings. Furthermore, PETG’s viscosity can lead to oozing, necessitating careful temperature control and possibly making it challenging for beginners to achieve perfect prints.
Material Settings of PETG Filament
| Setting | Value |
|---|---|
| Print Temperature [°C] | 220 – 260 |
| Build Plate Temperature [°C] | 60 – 90 |
| Print Speed [mm/s] | 40 – 60 |
| Cooling Fan [%] | 30 – 60 |
| Enclosed Build Chamber | Not Required |
| Air Management | Recommended |
| Min Active Heated Build Chamber Temperature [°C] | Not Required |
| Drying | Recommended |
| Annealing | Recommended |
Achieving optimal print quality with PETG requires a balance between temperature, cooling, and speed settings, as well as regular maintenance of the nozzle to prevent clogging due to its sticky nature. A heated bed promotes first-layer adhesion, significantly improving the print’s overall quality and reliability.
Mechanical Properties of PETG Filament
| Property | Value |
|---|---|
| Shore Hardness | D70 – D80 |
| Specific Gravity [g/cc] | 1.23 – 1.27 |
| Tensile Strength at Break [Mpa] | 50 – 75 |
| Elongation at Break [%] | 5 – 20 |
| Flexural Strength [Mpa] | 60 – 80 |
| Flexural Modulus [Mpa] | 2000 – 3000 |
| Impact Strength Charpy 23˚C [kJ/m²] | 20 – 40 |
| HDT B [°C] | 70 – 80 |
| Tg [°C] | 80 |
PETG’s mechanical properties underscore its robustness and versatility, making it suitable for applications requiring a blend of strength, flexibility, and environmental resistance. The toughness of PETG, combined with its heat resistance, positions it as an excellent alternative to more traditional filaments.
Material Comparison
| Material | PLA | ABS | PETG |
|---|---|---|---|
| Print Temperature [°C] | 180 – 235 | 230 – 270 | 220 – 260 |
| Durability | Moderate | High | High |
| Ease of Printing | High | Moderate | Moderate |
| UV Resistance | Low | Moderate | Moderate |
| Heat Resistance | Low | High | Moderate |
PETG offers a balanced compromise between PLA and ABS, marrying the ease of printing found in PLA with the environmental resistance characteristic of ABS, without the downsides of either. It’s the preferred choice for users looking for durable prints with relatively hassle-free printing experience.
FAQ´s about PETG Filament
What makes PETG a good choice for 3D printing?
PETG is prized for its blend of easiness to print, durability, and resistance to environmental factors like UV light and moisture, making it suitable for various applications.
How to prevent stringing when printing with PETG?
Optimizing retraction settings and printing temperature can significantly reduce stringing. It’s also beneficial to use a part cooling fan during printing.
Is PETG safe for food contact?
While PETG itself is considered safe for food contact, the safety of 3D printed objects also depends on the use of food-safe dyes in the filament and ensuring the printer is clean from contaminants.
Can PETG be used for outdoor applications?
Yes, PETG has excellent UV and weather resistance, making it well-suited for outdoor applications where many other filaments would deteriorate.
How does PETG handle temperature?
PETG offers good thermal resistance up to about 80°C, making it viable for applications in moderately high-temperature environments.
