Elephant's Foot in 3D Printing. How to Get Rid of It?

In the world of 3D printing, a defect such as "elephant's foot" is quite common, and in our opinion, it doesn't get enough attention.

For most 3D printing applications, this flaw can be overlooked as it doesn't significantly affect the end result.

However, when it comes to practical applications, elephant's foot can present serious problems. This defect sharply reduces tolerances, making it much more difficult to fit parts together.

For example, you want to fit one part to another, but you encounter a problem because the first layer is significantly larger than the subsequent ones.

In the architectural field, engineers can use 3D printing to check and determine the accuracy of a design before it is manufactured on a significant and costly scale. If there is a defect in the print, it distorts the representation of the final product.

For example, if a structural engineer is designing a building and the printout is faulty, it will not correctly represent the structure of the building.

We have been providing 3D printing services for several years, and the presence of elephant's foot is an unacceptable defect for most of our clients' projects.

We hope that with our preface we have convinced you that it's still worth getting rid of elephant's foot. And in this post, we will introduce you to the basic ways to fix this problem.

Some of our recommendations may seem complicated for beginners. But in fact, it's much more difficult NOT to know what to do than to have a clear step-by-step guide.

What is elephant's foot in 3D printing?

Elephant's foot is a deformation of the 3D model that occurs under the influence of temperature and the weight of the model.

The upper layers press on the still not cooled first layer and under the influence of the object's mass, the first layer is flattened and its geometry is distorted. Accordingly, the higher your model, the more pronounced the elephant's foot effect.

In our blog, we have repeatedly mentioned that printing the first layer and calibrating the platform are critical for obtaining quality prints. And, describing the causes and ways to eliminate elephant's foot, we are again forced to return to this topic.

8 ways to get rid of elephant's foot in 3D printing.

Among all the numerous limitations and problems that users face in 3D printing, elephant's foot remains one of the easiest to solve. You just need to conduct several test operations to determine which factor in your case is causing this effect.

1. Calibrating the 3D printer bed.

Fixing almost any 3D printing problem starts with calibrating the platform. And elephant's foot is no exception.

This effect can appear due to an improperly calibrated bed or incorrectly set nozzle height.

Positioning the nozzle too close to the 3D printer platform causes the first layer to be pressed too hard into the platform and flattened.

The principle of calibration is that the nozzle should be at the same distance from the platform over the entire working area of the printer.

In addition, as is often the case in 3D printing, proper platform alignment can generally lead to improved print quality for your projects.

Calibrating the 3D printer platform is a key factor in 3D printing, allowing you to eliminate many 3D printing problems.

2. Reducing the print bed temperature.

A high bed temperature prevents the layer from cooling sufficiently.

Fusing subsequent layers of the part onto it leads to compression of the object and the manifestation of elephant's foot.

Usually, the bed temperature is set according to the recommendations of the plastic manufacturers. The correctly chosen temperature ensures good adhesion of the layer to the platform.

If you observe the elephant's foot effect, try lowering the platform temperature.

Don't rush when performing this process. It is recommended to gradually reduce the temperature by 5 °C until you start getting quality prints.

If you have reached the minimum recommended temperature for the platform, but the problem has not disappeared, most likely elephant's foot is caused by a different reason and you should consider the other options.

3. Set cooling for the first layer.

In most slicers, cooling of the first layers is disabled by default. Turning off the fans on the first layer ensures good adhesion of the part to the platform.

But we have already found out that elephant's foot appears when the first layer does not have time to cool down.

Increasing the initial fan speed to 5 or 10% will provide faster cooling of the filament and prevent flattening of the initial layer.

To improve adhesion, we recommend you use 3D printing adhesive spray.

4. Increase the print time of the first layer.

Increasing the print time of the initial layer is also a cooling-related solution, but instead of activating/increasing fan speed or lowering bed temperature, we set a low print speed for the first layer.

This will give it time to cool down before the printer starts printing the 2nd layer.

If the first layer hasn't had time to cool down, applying the second layer compresses the first layer. This problem can also lead to incorrect dimensions of your part not only horizontally but also vertically.

It is also obvious that using quality filament for 3D printers with the same diameter along its entire length ensures uniform extrusion and reduces the likelihood of elephant's foot appearance.

5. Reduce the flow rate of the first layer.

Perhaps your printer is set to over-extrude, and too much plastic is being squeezed out on the initial layers. Excessive extrusion may also be due to your nozzle being too close to the platform. We mentioned this in the first point of our guide.

You can calibrate the printer using our guide on setting up extruder steps.

How to calibrate extruder steps (E-steps).

Or you can simply reduce the flow rate of the first layer to 95%. This will have no effect on first layer adhesion but will affect elephant's foot.

6. Adding a raft to your model.

A raft is a horizontal grid created by laying plastic strands on the platform.

Since the elephant's foot problem occurs between the work platform and the first layer, the raft will take this hit.

This method will certainly rid you of elephant's foot, but it is more of a workaround than a solution to the problem.

Using this option, you will get a rough surface on your part and you will have to spend some time removing the raft. Nevertheless, you can consider this as a useful alternative, especially in cases where you need to fit one part into another.

7. Using chamfers in models.

There are cases when it is not possible to get rid of elephant's foot at all. All options seem incapable of providing the expected results.

If setting up and calibrating the printer is a tedious process for you, and a small change to the 3D model seems like an easier way, then choose this option.

All you need to do is add a small 45° chamfer to the bottom of your model. The figure shows two identical parts. On the left is a part with a chamfer, on the right without.

Any modeling software has a set of functions for creating chamfers and it usually doesn't take much time.

The upper layers will press down on the first layer with their weight, and the chamfer will compensate for the appearance of elephant's foot on your print.

8. Elephant's foot compensation in the slicer.

An even simpler method of getting rid of elephant's foot is compensation using a slicer. Cura, one of the most popular and widely used slicers, has implemented this setting in its software.

This parameter is called "initial layer horizontal expansion" and is located in the Shell section.

You can also easily find it by typing the word "elephant" in the search bar.

In Slic3r and PrusaSlicer this parameter is called "Elephant foot compensation".

In Slic3r you can find this parameter here: Print Settings tab -> Advanced settings

In PrusaSlicer, the parameter is located in Print settings - Advanced - Elephant foot compensation. To access this parameter, PrusaSlicer must be in advanced or expert mode.

Simplify3D has a "horizontal size compensation" setting. By default, it applies to all layers, but you can limit it to only print the first layer.

To calculate the correct compensation value, we recommend you print a test cube. After printing, measure the dimensions of your cube at the top and bottom.

Let's say the dimensions of the cube at the top are 20.02 mm, and at the bottom 20.3 mm (elephant's foot).

To calculate the compensation factor, substitute these values into the following formula:

(20.02-20.3)/2=-0.14.

We got a negative value, and this is exactly what needs to be set in the slicer. In essence, this method creates a chamfer without changing the model itself, but using a slicer.

Conclusion.

Elephant's foot on a 3D printer is a common error that is easy to fix.

In this post, we have described several approaches that will help achieve the best possible results.

It is important to understand that points 1-5 actually solve the elephant's foot problem, while points 6-8 simply hide it.

Using a raft will rid you of elephant's foot, but you will spend more time and materials and not get a smooth bottom layer surface.

We recommend trying simpler solutions first that don't take much time.

If you have identified the cause that is causing the elephant's foot defect, then use a specific solution aimed at eliminating the cause.

Problems like elephant's foot can hinder motivation for a while, but they can't stop those who are focused enough on achieving the expected results.

A little testing and patience and you will not only get quality prints, but also gain additional experience that will help you in solving other 3D printing tasks.

If you want to unlock the hidden potential of 3D printing, you must solve these small problems on your own. Learn and grow by printing amazing designs.

Happy printing!