Configuring the settings of a 3D printer is a topic that contains many intricacies, primarily due to the number of components that each require a separate set of correctly tuned parameters for the 3D printing process to go smoothly.
Among all the settings of the 3D printer, the extruder parameters are, without a doubt, the ones that stand out the most, essentially responsible for controlling the flow of the plastic, which is the heart of the 3D printing process.
Today, we will be examining the extruder E-step value calculation procedure, which is one of the pillars of extruder calibration that allows the extruder motor to operate correctly during the print and push out the right amount of filament.
So, how can you calculate the extruder E-step value?
In a nutshell, the process of calculating the extruder E-step value is about finding the difference between the calculated amount and the actual amount of filament extruded by the 3D printer, which tells us whether the E-step value is too low (under-extruding) or too high (over-extruding).
Next up, we will dive deeper into the e-step calculation process, find out how to set the calculated E-step value in the 3D printer, discuss the purpose of the e-step value, and finally, present you with an interactive e-step calculator you can use to quickly calculate the e-step value for your 3D printer without effort.
How to Calculate Extruder E-Step (Steps per Millimeter)?
While calculating the extruder E-step value is a straightforward process, for the most part, it’s vital to be careful, as even a slight mistake in the value you have found will cause your 3D printer to extrude incorrect amounts of plastic.
Below is a detailed step-by-step guide we recommend following to calculate the extruder E-step value for your 3D printer:
- If your printer has a Bowden extruder, remove the PTFE tube from the extruder end.
- Find out the current E-steps value of your 3D printer and note it down. In Marlin firmware, you can achieve this by running the M92 G-code with no parameters (or M503 in older versions).
- Heat your printer’s hot end to the temperature you would regularly use with the filament you will be utilizing.
- Load the filament directly into the extruder.
- With the help of calipers, measure an arbitrary length (longer than 110mm for good measure) of filament between the opening of the extruder and the filament spool, such as 130 mm, and mark the point on the filament with a marker.
- Extrude 100 millimeters of the filament by either using the LCD panel of your 3D printer or connecting your 3D printer to an interface such as OctoPrint.
- When the extrusion process is over, measure the length between the opening of the extruder and the mark you have placed on step 4, and note the value down.
- Subtract the value you have found from the length you have used for step 5, which was 130 mm in our example.
- Multiply the current E-step value (step 2) with 100 (step 6) and divide the resulting value by the value you have found in step 8, which will be your new E-step value.
To make the calculation process clearer, let’s go through a quick example where we assume that the length we have found in step 7 is 20 millimeters, and the current E-step value is 90.
Current E-step value -> 90
Mark point (step 5) -> 130 mm
Inputted extrusion amount (step 6) -> 100 mm
Actual extrusion amount -> 130 (Mark point) – 20 (assumed) = 110 mm
New E-step value -> 90 * 100 / 110 = 81.81 mm
We recommend refraining from using flexible (TPU) filament for calculating the E-step value, as the flexible nature of the filament can throw the calculations off.
How to Set the E-Step (Steps per Millimeter) Value of Your 3D Printer?
After calculating the extruder E-step value and ensuring that it’s correct, all there is left to do is transfer the value you have found to your 3D printer before moving on to the printing process.
To set the E-step value of your 3D printer after you have calculated the optimal figure, you can either utilize the related section in the LCD panel of your 3D printer or send the G-code that allows you to set the E-step value in your firmware.
For instance, on your Ender 3’s LCD panel, you can find the section for setting the E-step value by navigating to the Configuration, Advanced Settings, Steps/mm, and E Steps/mm options, respectively, and set the E-step value through this interface.
On the other hand, in Marlin firmware, the G-code for setting the E-step value is M92 (Set Axis Steps-per-unit), which you will need to use the E parameter and the value you have found.
For instance, if the optimal E-step value you have found is 81.81 mm, following the example from the previous section, you can utilize the G-code below to set the E-step value:
Remember to save the modification to the EEPROM to make it permanent by using the corresponding section on the interface of your 3D printer or the M500 (Save Settings) G-code (Marlin).
What Is the Purpose of the E-Step (Steps per Millimeter) Parameter?
While we can consider the E-step parameter to be on the more advanced side of things than standard parameters such as print temperature or print speed, it actually has a straightforward explanation that isn’t technically complex at all.
In a nutshell, the E-step value is the number of steps that your 3D printer instructs the stepper motor to take whenever it takes an instruction to extrude 1 millimeter of filament.
When the E-step value is configured correctly, your 3D printer will always extrude a millimeter of filament when you instruct it. On the other hand, when misconfigured, the actual amount of filament extruded will be more or less than 1 millimeter when you order the 3D printer to extrude 1 millimeter of filament.
Interactive Extruder E-Step (Steps per Millimeter) Calculator
In this section, you can find an interactive extruder e-step calculator, which allows you to input the necessary parameters for the calculation and obtain the optimal E-step value without performing any calculations yourself.
Correctly calculating the extruder E-step value and configuring your 3D printer with the value you have found is essential to the success of your prints, as a misconfigured E-step value will prevent the 3D printer from extruding the correct amount of filament.
To quickly recap, you can calculate the optimal E-step value for your 3D printer by marking a point on your filament to find the length difference between the amount of filament your 3D printer extrudes and the amount you specified extrude, and using the formula below:
(Current E-Step Value * Specified Extrusion Length) / Actual Extrusion Length
After calculating the optimal E-step value and inputting it into the configuration of your 3D printer, we highly recommend running another test print with the same methodology to ensure that everything is in order, in which case the specified extrusion length should be equal to the actual extrusion length.
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.