Why Won't Filament Stick to My 3D Printer Bed? - Your Ultimate Guide

Hello, Aussie 3D printing enthusiasts! Are you having a bit of a not-so-sticky situation with your 3D prints? Well, you’re not alone. It’s a common issue, especially when printing with ABS and PLA. But don’t worry, we’ve got you covered with some easy solutions to get your parts back to printed perfection!

Bed Leveling

First up, let’s talk bed leveling. If your printer has an adjustable bed and you’re having issues with sticking, check to make sure your bed level is flat. An uneven bed could mean that one side is closer to the nozzle while the other side is too far, creating a tricky print environment. If your bed is uneven, it can result in your print warping or breaking. The process for leveling your bed depends on your printer. Some printers, like the Creality Ender 3 S1 printers, are equipped with automatic bed leveling, but you also have the option to manually level your bed. If your 3D printer does not have auto-leveling, you will need to level it yourself. The most common methods of manual leveling is the paper trick. Being the most common a simple search on Youtube will result in many videos showing you how.

Nozzle to Bed Distance

Next, let’s chat about the distance between the bed and the nozzle. There’s a sweet spot here – not too close, not too far, but just right. If your 3D print is not sticking to the bed, check the distance between the bed plate and the nozzle. If the nozzle is too close to the bed, then the filament will not be able to come out, or the extruder could damage or drag the previously printed layer. On the other hand, if the nozzle is too far, the filament will not properly place on the bed and will not be able to adhere. The filament should be close enough to the bed so that it is slightly squished onto the bed’s surface, allowing it to grip onto the bed. This can also be controlled in your slicer settings. We find a first layer height of 0.25 seems to give us the most consistent results.

Nozzle Speed

The speed of your nozzle can also play an important role. Especially when printing the first few layers, it’s important to find a sweet spot for the nozzle speed. Slowing down the nozzle’s speed gives the plastic more time to bond to the bed and get a better grip. If you print too quickly, the filament may not stick to the bed because the plastic cools off too quickly. After you have laid down your first few layers and feel confident in your print’s bed adhesion, you can resume the nozzle to a normal speed. Most of the popular slicer software have an option to set the first layer speed. 15mm/s is a good starting point.

Automatic Bed Leveling

Automatic bed leveling probes such as the BL Touch are a feature that can help ensure that your first layer sticks properly to the bed. This feature adjusts the bed level based on the readings it gets from a sensor on the printer. It compensates for any unevenness or tilt in the bed, ensuring that the nozzle distance from the bed remains consistent, which is crucial for that first layer adhesion. So if your printer supports it, make sure to use it!

Bed Temperature

Another thing to consider is the bed temperature. The temperature of the bed can have a significant impact on print adhesion. For certain materials, such as ABS, a heated bed can be essential for proper adhesion. Even for PLA, which can sometimes be printed on a non-heated bed, a little bit of heat can help improve adhesion. The temperature should be adjusted based on the type of filament you are using, so make sure to check the recommended bed temperature for your specific filament.

Use a Bed Adhesive

If you’re still having trouble getting your prints to stick, it might be time to try using a bed adhesive. A bed adhesive can provide that extra level of adhesion needed to keep your prints in place. There are several types of adhesives you can use, such as glue sticks, hairspray, or specialty adhesives made for 3D printing. When applying the adhesive, make sure to spread it evenly across the bed and wipe off any excess with a dry cloth.

PEI Sheet

You might want to consider using a PEI (Polyetherimide) sheet on your printer bed. PEI is a type of plastic with excellent adhesive properties when heated, making it perfect for a print bed. When it cools down, it also releases the printed part quite easily. This means you get the benefit of great adhesion during printing, but it’s still easy to remove your part when the print is done.

3D Printer Enclosures

To address warping issues, especially with certain filaments, consider using a 3D printer enclosure. Enclosures help maintain a consistent temperature and protect the print from external drafts. The controlled environment inside the enclosure minimizes temperature fluctuations, reducing the likelihood of warping and improving overall print quality.

Filaments

Certain filaments are more prone to warping than others. Here are some common filaments and their characteristics regarding adhesion:

• PLA (Polylactic Acid): PLA generally has good bed adhesion properties and is less prone to warping. It’s a great choice for beginners and a wide range of applications.
• ABS (Acrylonitrile Butadiene Styrene): ABS can be more challenging to work with and has a higher tendency to warp. Using an enclosure and ensuring proper bed adhesion are crucial when printing with ABS.
• PETG (Polyethylene Terephthalate Glycol): PETG has good adhesion properties and is less prone to warping compared to ABS. It’s a popular filament for functional prints.
• TPU (Thermoplastic Polyurethane): TPU is a flexible filament that usually adheres well to the bed. However, using a heated bed and proper bed leveling are important for optimal results.
• Nylon: Nylon can be tricky to print and has a tendency to warp. An enclosure, along with other adhesion techniques, can help improve results when working with nylon filaments.

Cleaning

Lastly, cleaning your bed is the most important step. Greasy finger prints and residue left from the filament can build up on you glass or PEI sheet. Simply wiping down with IPA (Isopropyl Alcohol) or washing with warn soapy water usually does the trick.

Remember, every 3D printer is a little different, and what works best for one might not work as well for another. It might take some trial and error to find the right combination of techniques for your specific printer and filament.

Special Mention

If you’re still having trouble or if you want to dive deeper into the science of 3D printing, check out these useful guides:

• The calibration guide by Teaching Techs is a fantastic resource. You can find it here.
• Ellis has a detailed guide on first layer squish and many other aspects of 3D printing. Check it out here.

Happy printing!