When you have a 3D printer and a PETG filament, nothing can give you as much delight as getting an object printed from it.
With all your skills, you can easily build stuff like smartphone holders, 3D printer replacement parts, clamps, hinges, or shelving brackets.
But what if something goes wrong? Something like PETG not sticking to bed properly?
What will you do?
Don’t worry. This is actually one of the common issues of this material and there are heaps of reasons why it happens.
Because the reasons are different, the solutions would be different too. This is what I’ll explain here.
What Is PETG?
PETG is short for Polyethylene Terephthalate with a glycol modifier. It is one of the most common polymers that is used presently.
Take a look at any kind of clear plastic bottle or food packaging, there’s a high chance that it’s constructed with the material Polyethylene Terephthalate.
The extra-G i.e. the Glycol makes it easy to print structural components with 3D printer. Hence, you get more flexibility and impact resistance without hazing and brittleness.
As a 3D printing filament, PETG is super versatile. It has stable printing properties so you get objects of any shape. Moreover, it can withstand low-heat or high-strength environment.
Typically, you can say PETG has got the ease of use from PLA and durability from ABS. So, you will get the advantages of different materials in one. You can use its ductility traits to design some flexible geometry-like objects.
- Extremely durable and warp-resistant. So, you won’t be fretting about the objects falling off over the build plate.
- Very sticky. Even if you use the PETG filament with textured PEI sheet, it will stick itself to the bed.
- UV resistant. You can use 3D printed objects outside and get them exposed to sunlight. The object will still stand strong.
- Odorless. It does not emit harmful gas elements when printing, so there won’t be any smell.
- Blobs or zits. Sometimes the outer part of the print can come covered with random zits and blobs. However, you can fix it with right flow rate setting.
- Stringing. PETG can give you stringing issues if you have the setting wrong.
- Stickiness. Since the filament is super sticky in nature, you may have a hard time separating the prints from the plate. That said, you can get rid of it by using a hair spray beforehand.
- Absorbs water. Due to this, the PETG might not stick to the bed properly.
What To Do if PETG Filament Not Sticking To Bed?
1. Set The Temperature Right
PETG will not adhere to the print bed if you set the temperature wrong. If you set the temp too high, it’ll be prone to stringing and oozing. Meanwhile setting it too low would not make the material set, thus it may crumble and tear.
However, the temperature varies accordingly with the type of extruders, brand of printers and filament you’re using. For instance, the hotter filament should work better with a higher temp of the nozzle and build plate.
Typically for the nozzle, the recommended range of temperature is between 230°C and 250°C. So, I would suggest you start with 230°C. Play around with 5°C higher or lower unless you successfully get the perfect print quality.
As for the build plate, adjust the setting between 70° and 100°. Make sure you preheat the bed at least 10 minutes before using filament. This will cause the bed to heat evenly and raise the ambient temperature to prevent warping.
2. Modify The Fan Settings Correctly
The speed of the fan plays a big role in influencing adhesive properties. If you don’t adjust the fan right, sticky threads and blobs will form when the material cools down. As a result, the PETG will not reach the print bed from the nozzle let alone sticking to the bed.
The rule here is to keep the fan turned off when printing the first three layers of PETG. This way, the high temp will work to stick the interlayer better.
If the fan blows too hard during the initial stage, the material will remain cold and thus, the layers will end up holding poorly. Not only that, there would be entrained infills and unclean corners.
When printing the fourth or fifth layers, you can turn the fan on and start with 30% speed. This will ensure the material stays securely on the blade and that the final object doesn’t become very soft.
Increase the speed to 50% or more for printing bridges, getting more details, having short layers or extreme overhangs.
3. Get The Right Plate Material
3D printer always works to make one layer of material build on the previous layer. To get the structure right, the first layer has to be printed properly and individual layers must bond well; otherwise, the object will warp and fall off. This will also cause the following layers to not stick properly.
If you want the first layer clean, then make sure to choose the right plate material. Out of many, I would suggest 5 options.
A. Normal Glass
Usually, glass material always offers a glossy smooth bottom for 3D prints. The material is very stiff and flat, and it doesn’t warp over time. As it comes dense and boasts low thermal conductivity, it takes longer to heat up. This is good for the printing as it results in spreading the heat more evenly on the build area.
Some of the common types of glass for build plates are borosilicate and mirror tiles.
When it comes to PETG bed adhesion, pair the glass with adhesives like hairspray, glue stick or painter’s tape. All of them help the bottom layer stick ideally and smoothly.
B. Polyetherimide (PEI)
Polyetherimide or PEI is a textured, flexible surface perfect for different types of filament. It offers strong adhesion for 3D-printing objects and a smooth finish. You don’t even need any kind of adhesive for PEI. So, it’s a very hassle-free option to pick.
It has incredible mechanical properties including high or low temp resistance, high wear resistance, radiation resistance, chemical resistance and electrical insulation characteristics. You’ll also find the plate in different colors.
However, to get it to stick, you may have to smoosh the first layer slightly. Once the object gets cooled down, it will pop off easily.
This is a very flexible option. It works as a multipurpose sheet coming with an adhesive back that you can peel off easily to stick to the bed.
After you are done with the prints, you can easily remove the print from the sheet and clean the surface.
BuildTak is ideal for FDM 3D printer. It gives you a smooth 3D printing experience. The best part of the build plate is that your PETG would stick strongly to this surface.
Not just that, you can even place a magnetic base on the top of the BuildTak sheet over the print bed. Both the sheets will connect nicely as well as can be slid away from the bed with ease.
Garolite refers to a fiberglass or epoxy laminate material. This surface does not need any adhesive substance. You can even use it without preheating the bed.
Different high-end 3D printers come with a Garolite build plate, it prevents the PETG from getting warped. The texture of such type can get the most difficult filament to adhere well to it.
Although it’s not very popular, you would find it great.
It has a flexible adhesive on its surface. It lets you first peel the build surface off the magnetic base and later, peel it from the bottom of the object you printed.
One amazing factor is that it’s very child-friendly. Your kid doesn’t need any advanced tools to remove the prints. Plus, it doesn’t have any sharp edges or spring steel to deal with.
4. Correct The Print Speed
Print speed would be different for different types of PETG filament. This is because the properties of each filament differ.
However, the recommended range would be between 60 to 120 mm/s. If you go too slow, you’ll have stringing, oozing and deformed parts. Contrariwise going too fast will result in low print quality, extruder skipping and poor layer adhesion.
Thus, to avoid this, I would recommend that you start with 20 to 25 mm/s for the first layer and the exterior wall. Then increase it gradually. Again, this depends on the filament.
You may get a good print quality with the following setting-
Speed For Print Moves
|Small Perimeters||25 mm/s|
|External Perimeters||35 mm/s|
|Infill and Solid Infill||100 mm/s|
|Top Solid Infill||50 mm/s|
|Support Material||50 mm/s|
|First layer speed||25 mm/s|
5. Correct The Nozzle Spacing
Make sure there is a slightly bigger gap between the nozzle and the print bed. The ideal distance would be 0.1mm. It’s the thickness of an index card or 2 pieces of paper.
If the nozzle is set too close, the flow won’t go smooth and can cause the nozzle to jam. If you set it too far, the PETG won’t stick to the heated bed.
To get the best result, you can use an index card and match the gap.
6. Set The Retraction Right
One common problem with the PETG is that it can get very “stringy”. It happens when the nozzle moves over the area and prints another section of the object.
Even though the nozzle doesn’t push the PETG out, its sticky nature makes it pull the remaining filament to cause stringiness across other parts of the object.
But you can combat this problem once you set the Retraction setting right. It pulls a bit of PETG back into the nozzle before it changes layers or moves them.
The right setting will help you lower the stringing effects to a great extent.
I suggest you set the retraction speed to around 50 mm/s and decrease gradually if damage occurs. The distance should be 5mm initially but you can adjust it up or down by 1 mm unless you find the stringing gone.
7. Keep The PETG Dry
PETG is a hygroscopic material. It easily absorbs moisture from air when you leave it outside and hydrolyses when it’s wet. As a result, the interlayer bonding will be weaker on the molecular level and PETG will not stick to the print bed properly.
So, never get the filament exposed to high humidity or temp fluctuations otherwise it will dissolve and become brittle.
Although changing the characteristic of the material is impossible, you can get rid of such issues in 2 ways. First one is dehydrating the filament roll in an oven at 60°C for around 6 hours.
Second, you can store the filament roll in an airtight container with lots of desiccant for around 24 hours. Silica gel or dry beads would be great in this case. They work to prevent humidity inside the box from getting too high.
You can find several special storages that help keep the filament dry. One such special storage would be SUNLU dryer box. It lets you adjust the temperature of the box depending on the type of 3D filament you have. Not only that, you would find it easy to use and carry because of its simple design and lightness.
8. Get High-Quality Filament
One of the major reasons why PETG isn’t sticking. Low-quality filament can result in poorer adhesion. If you want the best options for filament, I would suggest OVERTURE PETG Filament or AMOLEN PETG Filament. Both measure 1.75mm in diameter and come in 1kg.
A. Overture Filament
This product guarantees to be free of clogs and bubbles so you get a smooth 3D printing experience. Moreover, it has high impact strength. If you want the spark in your object, this would be great.
B. AMOLEN PETG Filament
The filament won’t have any jam, bubbles, or warp issues. It promises to melt well and flow smoothly. You would also get the kind of shaping you want with this very filament. Not just that, it’s compatible with a variety of 3D printers.
9. Keep The Print Bed Clean
It’s normal that frequent use of the printer will cause deposits to form on the bed, particularly when you heat it.
Usually, high temp can make the filament adhere to the surface. So, when you remove any object after you’re done with the print, it may leave residue on the bed. As a result, you may not get proper adhesion on your next project.
To avoid this situation, it’s important to inspect the bed after each use. Clean it immediately if you find it dirty.
Some of the methods are-
A. Dishwashing Liquid And Water
If the bed is a bit dirty, then you just need to damp the cloth with dishwashing liquid and water and clean with it. Make sure your bed isn’t hot during the process.
I find Dawn Dish Soap Ultra Dishwashing Liquid very effective in this case. It can remove the light dust easily.
B. Glass Cleaner
If you’re using glass bed, then glass cleaner would be simply great. Just apply the glass cleaner and leave it. After that, wipe it over with a dry cloth. Not only it will remove grease stains but adhesive remnants too.
This Seventh Generation Cleaner can be an excellent pick. It’s tough on grease and dirt and cleans the glass very well.
Isopropanol is great for cleaning the most annoying adhesive. So, it ensures incredible results. Keep in mind that the print bed has to be cool during this process.
Also note that the Isopropanol agent evaporates very fast. So, use a soft sponge for cleaning. It will let you remove the stain faster.
Make sure to use 99% solution if you don’t want any sign of streaks on the bed.
You can think of having Solimo 99% Isopropyl Alcohol for the job. It comes in a set of 12 and each is 16 fl oz. The product can remove the toughest stain incredibly.
You must inspect the actual reason why is your PETG not sticking to bed well before trying out the solutions.
It can be due to low-quality filament, wrong temp setting or incorrect distance of the nozzle or anything.
For this, you must make sure that you get premium PETG filament first. Then, keep fine-tuning the settings unless you get the object stuck to the print bed well.
The solutions we provided are rather easy. Just follow the steps properly and see an efficient result.