What Is PETG Filament? [Ultimate Guide]

by Mike Brooks | Last Updated: January 28, 2022

What is PETG filament? When it comes to 3D printing, PETG is an acronym for Polyethylene Terephthalate (Glycol modified). It is a common polymer known for its durability and ease of use.

It is mostly used in the production of common plastics such as water bottles and food packaging items.

What Does PETG Filament Mean?

PETG is a Glycol modified version of Polyethylene Terephthalate (PET) commonly used to produce water bottles.

It is a semi-rigid material with excellent great resistance and a smooth surface which can make it wear out fast. The material also has outstanding features such as great temperature resistance, which allows the end product to cool with little warpage.

With an 80°C glass transition temperature which is less than ABS (105) but more than PLA (60-65°C), printed parts can handle any heat and normal activities with slight shrinking without deforming.

Is PETG Filament Good?

Being a popular 3D printing filament, PETG plastic is one of the most durable materials that are temperature resistant and easy to print.

It combines the most valuable mechanical properties of ABS filament (the mechanical and rigid features for functional parts) with the ease of printing that PLA filament provides.

3D printing with PETG filament (see on Amazon) delivers results that give the materials a clear look which is less fragile and simpler to use than the primary form of PET. (Polyethylene Terephthalate)

What is The Perfect PETG Print & Heated Bed Temperature

PETG 3D printing will go along smoothly at a temperature of 230°C -260 °C. Printing too hot will cause additional slinging or blotching, while printing too cold may take the rind off easily.

Since thermal properties vary in most cases, you will have to try the PETG filament your purchase to decide the most appropriate temperature range to print.

PETG 3D printing requires a heated bed temperature at 70°C – 80°C. Heating your heated bed temperature above the glass transition temperature of PETG(80°C) is not recommended when 3D printing with PETG filament.

What is PETG Filament Used For?

As a 3D printing filament, PETG has proven its worth as durable material that is easy to use.

It is the perfect filament to combine strength and flexibility and manufacture water bottles, food packaging materials, and other everyday plastic items.

Polyethylene terephthalate glycol is ideal for producing flexible materials with outstanding resistance to shocks, such as protective parts and other pressure-clad items.

Getting the Best Out of PETG Filaments

Here are a few tips on how to get the best out of PETG filaments:

1. Printing The First Layer

Like printing using any other filament, printing the first layer right is essential for the final print on the end product. Failure to get a good first layer might force you to consider reprinting the materials. So, you must know the basics of starting a print to build it to completion.

With the different types of heating beds and adhesive solutions, here’s how to make the most out of printing the first layer;

2. Glass Bed Printing

Glass has a fine texture, and this dispatches a glossy heating bed surface on the print material.

To use a glass bed when printing, you need to have a heated print bed surface to get the best results. However, sometimes filaments tend to stick out so well that chunks start to tear out the glass print bed (see on Amazon).

Take caution when printing with glass and ensure you deal with the remnants from your print bed safely.

3. Buildtak

This great 3D printing surface prints perfectly with a PETG filament. It works with both PLA and ABS switching covers or plates, given that it’s a universal print bed surface. Although it might get worn out with time, print parts adhere very well.

4. Smooth and Powder – Coated PEI

Whether in powder form or from Layer Lock, PEI print surfaces (see on Amazon) are the best option for PETG.

However, exercise caution when using PEI because PETG can stick to it permanently and eliminate huge parts of the print bed surface.

Layer Lock build surfaces are not as sensitive. They can withstand 3D PETG printing directly on the print bed with ease and prints popping right off.

5. Layer Lock Garolite

Although it is one of the best surfaces for 3D printing with nylon, Layer Lock Garolite is adaptable and can support PETG 3D printing.

Use the adhesion solution of your choice to acquire extra bed adhesion to improve your PETG 3D printing.

You can also decide to refresh it for more bite for the 3D prints to hold on to through a little roughening up with high grit sandpaper.

6. Blue Painter’s Tape Printing

Blue painter’s tape is an affordable and straightforward bed surface for 3D printing PETG filament materials like plastic bottles. The finish at the bottom might be level at first but will align with the painter’s tape texture.

In addition to the adhesion you get with painter’s tape, you also gain from a disposable print bed surface. PETG adheres to print bed surfaces exceptionally well until you observe tearing out of chunks or bonding with them permanently.

Blue painter’s tape 3D Printing (get it on Amazon) allows you to clean any extra tape sticking to the part and not tamper with your print bed surface, given that you’ll need to smear over the top of any other 3D printing build surface.

7. Deciding The Right Temperature

Monitor the filament that doesn’t end where it’s supposed to. Also, watch out for filaments that end up sticking on top of the nozzle since PETG tends to ooze and string.

In some cases, the blots of PETG filament may stick on the nozzle and end up in another part of the 3D printing that might harm the printer.

In case this happens, the blobs may cool and solidify, which can be detrimental to the nozzle during the printing process. This situation always causes a layer shift which could be a hazard to the 3D printer.

Is PETG Stronger Than PLA? What Are The Differences?

PLA is a bit easier to use for 3D printing than PETG given that PLA is more forgiving in terms of settings.

Both are easy to use but PETG is more durable, stronger, impact-resistant, and flexible making it a better option for your 3D printing materials. You don’t need a heated bed to print both materials.

The key differences between PETG and PLA include :

• PLA is more brittle than PETG
• PLA can be printed cold while PETG will need a heated bed.
• PLA supports are easy to remove while supports are hard to remove with PETG.
• Layer adhesion is unmatched with PETG leaving strong and durable prints.

You might like: PCTG versus PETG

How Much Does PETG 3D Printing Filaments Cost?

PETG 3D printing filaments are slightly more expensive than PLA and ABS. The starting prices of PETG plastic are around $24, whereas PLA starts at about $20.

Higher quality and industrial standard 3D printing PETG filament generally cost more, with starting price at around $55.

You can also choose PETG pellets to save money on filaments and have the equipment and resources for turning the pellets into filament.

Remember to dye it during this process for custom PETG colors and blends.

Does PETG Absorb Moisture? Is It Waterproof?

The excellent interface between PLA and ABS (best of both worlds): PETG is more rigid and can handle higher temperatures than PLA and other filaments while warping less than ABS.

PETG filament is slightly hygroscopic; it absorbs small amounts of moisture from the air, which affects the print quality of PETG parts over time, making them more fragile and bubbly over time.

You are recommended to keep all filament in a suitable filament storage container or other protector or a dry part of the room. You can also dry wet PETG filament with a filament dryer.

It helps remove most of the moisture and avoids the downsides of leaving filament out for too long.

Advantages and Disadvantages of PETG

Let’s look into some of the good stuff and drawbacks of PETG filament.

Advantages of PETG Filament

• Multiple color options: Like ABS and PLA, there are numerous options to choose from with PETG; you will not struggle to find the combination you want for a particular project.
• Excellent layer adhesion without deforming: PETGs stickiness provides great adhesion to the print bed leading to strong and durable materials. This makes it a better option for long and thin parts that are difficult to print with filaments like ABS.
• Good surface finishes: PETG print results come out glossy and glittery with a translucent, radiant finish. Though tastes and preferences might differ, most people enjoy the finish from PETG 3D printing.
• Odorless: PETG does not create bad smells from fumes while 3D printing, unlike ABS.

Disadvantages of PETG Filament

• Low scratch resistance compared to ABS: the glycol property that enhances PETG filament from PET in different ways makes it less scratch resistant. Materials can wear down over time and look less aesthetically pleasing.
• Ability to string, worsening surface finish: ensure that you fix your retraction settings as strings and hairs can affect the surface finish of your print materials.
• Poor for supports or bridges: the excellent layer adhesion feature comes at a cost; PETG supports or bridges can stick too well, creating hard to remove supports that can leave marks on the other materials.

How To Get The Best Results From PETG Printing

Let’s see what can you do to get the best results from PETG.

Use a good build surface

Some 3D printers come with a glass bed or blue printer tape already installed on the bed. Although these surfaces might work for PETG 3D printing, you are recommended to use a heated build surface for excellent results.

The heated bed can improve the first few layers’ adhesion, making things easier for future prints. Most heated beds come with a glass surface that allows you to print directly on the bed without applying any extra layers of tape or glue.

Use a dual extruder with a different filament for supports

Although it sticks well, PETG filament is notoriously poor for supports. If you are using a dual extruder 3D printer, print supports in PLA, or a specialized support material that works well with PETG and can easily be removed or dissolved after the printing process.

Precise, correct print settings

Adjust your PETG 3D printing settings to find the best retraction speed and distance settings within minimum chances of stringing and the best extruder and heated print bed for temperatures.

You should also consider turning off your cooling fan for the first few layers to prevent warping, then turn the fun off for the following layers in PETG prints.

Final Thoughts

With great mechanical properties and exclusive features such as the glassy surface of PETG applicable when using rafts to help separate easily from the raft and maintain a clean surface finish, print PETG is a favorite in the world of 3D printing.

If you set it up correctly, you will find printing with PETG a dream. Odorless printing, no warp, and excellent layer adhesion are just some of the fantastic 3D printing properties with PETG filament.

Michael Brooks is the founder of M3DZone.com. He sees a very bright future for 3D printing that's why his mission is to try and make this easy for everyone. Discover your hidden talent and creativity. You can follow here: Facebook, Twitter & Pinterest.