Maintaining your 3D printer frequently to ensure that it stays in good shape plays a vital role in obtaining high-quality prints, as there are plenty of physical factors that can affect your 3D printer adversely, which reflects on the quality of the models you print as a result.
Because of this, becoming familiar with the common techniques used in 3D printer maintenance is a vital part of the 3D printing journey and, in fact, as important as the standard tasks we regularly perform, such as configuring the slicer settings correctly or ensuring that the bed is level.
Today, we will be talking about the cold pulling process, which is one of the staples of 3D printer maintenance that every 3D printing enthusiast should be familiar with, and how we can apply it to the Ender 3 as efficiently as possible without problems.
So, how to perform the cold pull process on the nozzle of an Ender 3?
In a nutshell, performing the cold pull process on your Ender 3 involves getting a piece of filament that has a high melting point (such as nylon), heating the nozzle, pushing the filament in until it fills the nozzle, cooling the nozzle down, then pulling the filament back out, which will bring all the dirt clogging the nozzle with it.
Moving forward, we will dive deeper into the process of performing a cold pull on the Ender 3, discuss the primary purpose of conducting a cold pull and the suitable cases for it, and take a look at some handy tips that can help prevent the nozzle of your Ender 3 from clogging.
How to Perform a Cold Pull on the Ender 3 (Pro/V2)?
As cold pulling is a technique that is a lot more straightforward and technically undemanding than its alternatives, having a good grasp of how to perform it can usually save you a lot of your time and effort that is better spent on enjoying 3D printing instead.
Below is a detailed step-by-step guide you can follow the cold pull process on your Ender 3 to unclog the nozzle:
- Remove the filament you are currently using from your Ender 3.
- Detach the Bowden tube of your Ender 3 and put it away for now.
- Raise the Z-axis to a level where you have enough space to work comfortably.
- Heat the hotend to a slightly higher temperature than the required print temperature of the material (the filaments you printed with earlier) you’re trying to remove.
- Grab a piece (which should be long enough to fill the nozzle and still stick out for you to grab easily) of filament with a high printing temperature requirement, such as nylon or cleaning filament. The color of the filament should preferably be white to make things easier.
- Push the filament down the extruder until you see it poking out of the nozzle.
- Stop the nozzle from heating, and keep pushing the filament into the nozzle. At this point, the filament should still be going into the extruder and filling the nozzle up but not coming out of it. The nozzle should be full of the filament you’re pushing in for optimal results.
- Allow the nozzle to cool down to room temperature, then re-heat it to 85-90 degrees Celsius.
- Quickly but steadily pull the filament upwards and out of the extruder with the help of pliers. Be careful not to break the filament during this process.
When you pull the filament out, you should see the dirt gathered on the end that went into the extruder, which will be more easily visible if you have used white-colored filament, as we have mentioned earlier.
Please note that it can be necessary to conduct the cold pull process more than a few times depending on the severity of the clog, and as a result, we recommend repeating the process with a fresh piece of filament until it comes back entirely clean.
What Is the Purpose of Performing a Cold Pull on the Ender 3?
While the purpose of cold pulling makes it a process that you won’t need to perform too frequently, there is no denying that there will eventually be a scenario where you will need to use this technique to get your 3D printer back in working order.
The primary (and only) reason you will need to perform the cold pull process on your Ender 3 is to clean the dirt, such as remnants of old filament, in your nozzle that causes it to become partially clogged, creating problems such as inconsistent extrusion and under-extrusion.
While the cold pull method isn’t the most reliable way of getting rid of the clogs on your Ender 3’s nozzle, it’s the most straightforward and technically uncomplex one as it does not require nozzle disassembly, which makes it an option worth trying as the first step.
On the other hand, despite the cold pull method not being the best performer for removing clogs, it’s usually good enough to get rid of clogs that aren’t too severe, which accounts for the majority of the partial clogging situations.
How to Prevent the Nozzle of Your Ender 3 (Pro/V2) from Clogging?
Taking preventative measures is always better than facing a problem first and then having to fix it, as it both removes the chance of something going wrong during the fixing process and saves you a reasonable amount of time that you would otherwise have to spend on solving the problem.
Below is our list of recommendations to prevent the nozzle of your Ender 3 from clogging as best as possible:
- Clean the nozzle of your Ender 3 as soon as you finish a print with the help of tools such as needles, tweezers, and wire brushes. Performing the cleaning while the filament inside is still in its melted is optimal to ensure that you can remove it quickly and consistently.
- Ensure that the space between the nozzle and the print surface is always optimal. An incorrectly configured Z offset value and a bed that isn’t level are the two primary culprits that can cause such a problem.
- Ensure that you print with the nozzle temperature recommended by the manufacturer of the filament you’re using. Temperatures that are both too low and too high can cause the filament to stick to various parts of the nozzle.
- Refrain from using low-quality or degraded filament. Poor-quality filament and filament that have been damaged by factors such as moisture are unreliable to print with, and they can easily cause the nozzle to become clogged.
The cold pull technique is, without a doubt, the quickest way to free the nozzle of an Ender 3 from any partial clogs that are disrupting the extrusion and causing problems for the printing process, making it an essential instrument in any 3D printing enthusiast’s toolbox.
To quickly recap, let’s once more go through a condensed version of how you can apply the cold pull process to the nozzle of your Ender 3:
- Grab a piece of filament with a high melting point, such as nylon.
- Heat the hotend to a higher temperature than the filament you’re trying to clean out requires.
- Push the piece of filament through the extruder until you can see it come out of the nozzle.
- Stop the nozzle heating and manually push the filament in again to fill the nozzle.
- Let the nozzle cool down to room temperature, then re-heat it to 85-90 degrees Celsius.
- As soon as the nozzle reaches the temperature, pull the piece of filament out with pliers.
While you may need to follow this process a few times to ensure that you manage to catch everything that’s contributing to the clogging of the nozzle, performing the cold pull routine alone should be enough to clear out partial clogs in most cases.
Mike started his 3D printing journey with the Anet A8 when it first came out back in 2017, and has been obsessed with 3D printers ever since. Nowadays, he primarily uses his Ender 3 to print functional parts that make his life more convenient whenever possible.