There is no debate that cooling is one of the fundamental parts of 3D printing, as the thermoplastic that is exposed to incredibly high temperatures by the hotend for it to melt and flow freely out of the nozzle will quickly need to cool down to solidify and form a layer that can accommodate the upcoming layer of melted plastic.
While it all seems relatively straightforward when we put it like that, the fact of the matter is that cooling is one of the most complex parts of 3D printing, as, for a successful printing process, the amount of cooling needs to be just right, and not too much or too little.
Today, the topic of our article will be the application of too much cooling during the 3D printing process, where we will be discussing the signs that you will observe in such a case, in particular, as too much cooling is an issue that can silently ruin your prints, and leave you to wonder where the problem really is if you haven’t experienced it before.
So, what are the signs that indicate you might be applying too much cooling during the 3D printing process?
Below, you can find the most common signs that indicate the cooling fan speed is too high during the 3D printing process:
- The first layer detaching from the print bed completely
- The occurrence of warping on the first layer of the print
- The appearance of visible cracks on the 3D printed model
- The 3D printed model becoming extremely prone to physical damage
In the upcoming parts, we will be discussing each of the signs that you may potentially observe when your 3D printer applies too much cooling during the print more comprehensively, go through the process of optimally adjusting the cooling fan speed in detail, and finally, take a glance at the signs that may indicate that cooling is insufficient.
What Are the Signs of Too Much Cooling in 3D Printing?
Even though it may seem like a good idea to cool the melted plastic down as quickly as possible for it to solidify and gain structural integrity before losing shape, the fact of the matter is that too much cooling can also easily ruin a print.
Here are the signs that indicate you’re applying too much cooling during the 3D printing process, along with detailed explanations:
- The first layer, and hence, the 3D printed model, detaches from the print bed completely. When the first layer of the 3D printed model is cooled down too rapidly, the plastic won’t have enough time to form strong bonds with the print bed and practically solidify without any connection to it.
- Warping occurs in the first layer of the 3D printed model. Warping is a less-severe product of applying too much cooling compared to the entirety of the layer detaching from the print bed, with only the corners of the layer lifting due to the cooling causing the plastic to contract too suddenly and pull away from the print bed as a result.
- The final product has visible cracks in the areas where the layers connect. This problem is known as layer delamination, where the layers of the 3D printed model end up separating from each other due to the strength of adhesion between the layers being insufficient as a result of the application of too much cooling.
- The 3D printed model is prone to cracking, breaking, and basically any form of physical damage. Even in cases where the layers of the 3D printed model don’t separate during the 3D printing process, the weakness in adhesion can lead to the 3D printed model being prone to damage, where the slightest physical impact can cause the layers to lose any minimal contact that they had.
It’s worth noting that filaments with low glass transition temperatures, such as PLA, are highly unlikely to be affected by the usage of too much cooling, as they can easily remain above their glass transition temperature for a sufficient amount of time, regardless of how much cooling is applied.
How to Adjust the Cooling Fan Speed of Your 3D Printer Correctly?
Correctly adjusting the cooling fan speed is as challenging as it is vital for a successful 3D printing process, as the optimal fan speed depends on many factors that you will need to put into consideration, with even a tiny oversight potentially throwing the value off.
The first factor to keep in mind when adjusting the cooling fan speed is the type of filament you’re utilizing, as each filament type comes with different cooling requirements for a successful 3D printing process, and using the same fan speed value across distinct filaments will most likely result in over or under-cooling.
For instance, a low glass transition temperature filament, such as PLA, is often printed with 100% cooling fan speed, as there is no risk of the increased cooling causing the plastic to go below its glass transition temperature quicker than intended.
On the other hand, a high glass transition temperature filament, such as ABS, should be printed with minimal or no cooling since the plastic can quickly go below its glass transition temperature before the layers get a chance to form strong bonds with each other.
The second factor to put into consideration is the size of the layers, with smaller layers requiring more cooling (but not too much) to ensure that they have solidified by the time the next layer comes on top, while larger layers are unaffected due to having sufficient time to cool down naturally.
For instance, when printing a thin and tall model, such as a tower, which would naturally have small layers, it becomes essential to apply enough cooling to prevent the elephant’s foot issue from occurring.
On the other hand, when printing a model with larger layers, such as a box, you will have more freedom in optimizing the cooling fan speed, where you can go for higher values to increase surface quality or lower values to increase strength.
The third factor to take into account when configuring the cooling fan speed to be optimal is the availability of overhangs and bridges, as such parts will naturally require more cooling to be able to solidify and gain structural integrity due to the lack of foundation beneath them.
As a rule of thumb, overhangs and bridges will always require some cooling than the rest of the model, regardless of the filament you’re printing with, as they won’t be able to hold their shape long enough to cool down naturally.
Finally, the last optimization that you will need to make is for the first layer of the print, where cooling should either be completely turned off or applied at a nominal rate to ensure that the layer can form strong bonds with the print bed and become capable of acting as the foundation for the rest of the model.
Since the first layer is a special case due to its responsibility of connecting the rest of the 3D printed model to the print bed, it’s imperative to ensure that it sticks well enough to the print bed for the printing process to be a success.
What Are the Signs of Insufficient Cooling in 3D Printing?
Like too much cooling, insufficient cooling will also have adverse effects on the process of 3D printing, meaning that simply turning the cooling down to an arbitrary level upon noticing that it’s way too much is not a suitable solution for a successful print either.
Below are the most common signs that indicate the cooling during the 3D printing process is insufficient, along with explanations that further clarify their effect:
- The surface quality of the 3D printed model is low. When the plastic is not cooled at a sufficient rate, it will keep flowing and lose its shape before it solidifies, making it look like the plastic is smeared on the 3D printed model.
- The overhangs and bridges (if any) on the 3D printed model are droopy. As overhangs and bridges don’t have any foundation beneath them (unless supports are used), they will rapidly start drooping if they are left in their melted state for too long without external cooling.
- The elephant’s foot issue is present on the 3D printed model. When a layer comes on top of another layer without the previous one being sufficiently cooled and solidified, the added pressure can cause the layer to lose its structural integrity and expand as a result.
- The overall shape of the 3D printed model is deformed and not dimensionally accurate. As the plastic leaves the nozzle in a liquid state, it will eventually start moving towards the path of least resistance unless it’s cooled on time, which causes the 3D printed model to lose its original shape and form.
Utilizing a cooling fan speed value that prompts the 3D printer to apply more cooling than necessary to the plastic during the printing process will definitely have some adverse effects on your prints, making it vital to spot the signs that may indicate such a situation.
To quickly recap, poor print bed adhesion and poor layer adhesion are the two main problems that can stem from applying too much cooling during the 3D printing process, which present themselves in the form of signs such as the 3D printed model detaching from the bed, either fully or partially (warping), and structural weakness, leading to cracks and proneness to overall physical damage.
As applying too much cooling to the model during the 3D printing process can easily cause the print to fail and render the 3D printed model unusable, it’s vital to ensure that the cooling fan speed is set to a balanced value based on factors such as the filament being used and the shape of the 3D model.
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.