Bed adhesion is a frequently discussed topic when printing with PETG, as it’s no secret that getting PETG to adhere to the bed is usually much harder compared to PLA.
While there are a lot of factors that go into bed adhesion, such as print bed temperature, hotend temperature, cooling fan speed, and many more, the surface you’re printing on is also a significant factor to keep in consideration.
With plenty of different build surfaces to choose from, a common question is how well PEI surfaces work with PETG in particular, primarily due to PEI being one of the most popular surfaces available as of now.
So, should you print PETG on PEI surfaces?
PETG sticks exceptionally well to PEI surfaces, making PEI a fantastic option for printing with PETG.
As PETG can even stick way too much to PEI in some cases, we recommend going with a powder-coated PEI surface rather than a smooth one or using a separating agent (such as hair spray) on smooth PEI.
In the upcoming sections, we will take a more detailed look at why PEI surfaces are a good option for printing PETG, different types of PEI, solving bed adhesion issues between PETG and PEI, and preventing PETG from being stuck to PEI.
Should You Print PETG on PEI Surfaces?
With PEI being one of the most popular build surfaces and PETG being one of the most popular filaments, there is no surprise that many enthusiasts would like to learn more about the compatibility between the two.
PEI is one of the better surfaces you can use to print PETG on, as the common problem of bed adhesion a lot of enthusiasts have trouble with when printing with PETG becomes non-existent with PEI.
While there is a slight drawback to using PEI due to PETG sticking too well in some cases, you can remedy this issue by using a powder-coated PEI surface or applying separating agents to a smooth PEI surface.
So, what makes a powder-coated PEI surface better than a smooth one for printing PETG?
In a nutshell, as PETG sticks too well to smooth surfaces, a smooth PEI surface can often cause issues where the plastic gets stuck to the surface, both ruining the print and making it a burdensome process to remove the residue.
Since a powder-coated (textured) PEI surface is rougher, PETG won’t adhere to it as strongly as it does to smooth PEI surfaces. As a result, you won’t be facing issues where parts of the print are entirely stuck to the surface.
That being said, as it’s possible to prepare a smooth PEI surface with the help of separating agents such as Windex or hair spray, a smooth PEI surface can also work with some preparation.
How Do You Get PETG off PEI?
The most common issue enthusiasts face while printing PETG on PEI is being unable to separate the plastic from the surface due to the adhesion being too strong.
To remove PETG that has stuck to a PEI surface as efficiently as possible, we recommend following the steps below:
- Wait until the bed, the surface, and the PETG entirely cools down.
- Gently pull the larger pieces off the surface with your hands.
- Scrub the surface thoroughly with dish soap and water until the surface is free from plastic and grease.
- Leave the PEI in the mixture of soap and water for a few minutes.
- Scrub the surface one more time to ensure that it’s clean.
- Dry the surface thoroughly to prevent it from rusting. If the PEI stays wet for a prolonged amount of time, it can rust in some cases.
- If you’re using a smooth PEI surface, spray Windex or hair spray on the surface after the cleaning process is over, and let it dry. These separating agents will form a thin layer that will stop PETG from sticking way too much the next time you print.
While some sources recommend using sharp tools such as spatulas to scrape the plastic off, this can easily damage the surface if you aren’t careful. As a result, we do not recommend using any sharp objects on your PEI to get PETG off.
If there are pieces that you can’t get off with your hands, you can use plastic tools that aren’t sharp as gently as possible to refrain from damaging the sheet.
PETG Not Sticking to PEI – What to Do?
While an uncommon issue compared to PETG sticking to PEI way too much, it’s also possible for PETG not to stick to PEI in some cases.
To get PETG to stick to PEI as it should, we recommend following the steps below:
- Let the surface cool down completely and remove it from the bed.
- Prepare a mixture of water and dish soap in a large container, and place the PEI in the container.
- Scrub the surface thoroughly, and leave it in the soap water mixture for a few minutes.
- Scrub the surface once more, and remove it from the container.
- Dry the PEI as much as possible with a towel, and let it fully dry for a few hours.
- Place the surface on the bed again while avoiding touching the top side to ensure that the surface doesn’t get greasy.
As the main reason behind PETG not sticking to PEI is the surface being dirty from previous prints (especially if you have used a different type of filament such as PLA), cleaning it thoroughly with soap and water will ensure that it’s as good as new.
Can You Print PETG on Smooth PEI?
While powder-coated PEI is without a doubt the best option for printing PETG, smooth PEI can also work with the correct preparation.
While PETG adheres way too strongly to smooth PEI, which causes issues such as pieces of plastic being stuck on the surface and prints breaking off, it is indeed possible to print PETG on smooth PEI with the help of separating agents.
Separating agents such as Windex and hair spray form a thin film on the surface which prevents the plastic from adhering to the surface as much as it does, allowing you to print PETG on smooth PEI without issues.
While glue sticks are often recommended as a separating agent, we recommend avoiding them as much as possible as they create too much of a mess on the build surface.
There is no surprise that PEI surfaces are getting increasingly popular with the number of filament types they work with, and PETG is no exception.
To recap quickly, PEI is a great surface to print PETG on as it does an incredible job of preventing bed adhesion issues that we commonly observe while printing PETG.
As PETG can stick way too well to a point where it gets stuck on the surface, it’s best to go with a powder-coated PEI surface or use a separating agent such as hair spray if you already own a smooth PEI surface.