3D Printer PID Tuning. Useful Calibration Guide!

by Mike Brooks | Last Updated: June 25, 2022

Getting high-quality 3D prints requires you to use a well-functional 3D printer. Also, you need a compatible printer software version.

Still, your choice of filament will make a difference as it has to be appropriate for your 3D printing needs.

PID Calibration

Significantly, the next step before you begin printing is to get your 3D printer PID values correctly.

PID calibration or PID tuning’s main objective is to ensure you adjust the reaction of the PID controller to setpoint changes and minimize variability of control error.

In other words, PID settings help PID controllers hold measured process values of a set point or the desired value.

Appropriate 3D printer PID settings enable your printer heated bed and hot end temperature to function at a stable temperature.

If you control the nozzle temperature and the print bed temperature variations, you’re bound to increase the print quality.

3D Printer PID Tuning. What Is It Exactly?

3D printing technological advancement like Marlin firmware stands out in 3D printer heat control. It eliminates the need to control hot end and print bed temperatures by turning the heater on and off.

Instead, it uses a variable power adjustment approach to more innovative and accurate power output control.

PID refers to Proportional, Integral, and Derivative. So 3D printer PID tuning controls how your printer copes with your heated bed and extruder or hot end printing temperature adjustments.

If you successfully run PID tuning, these parameters enable your 3D printer hot end and heated bed to enjoy a more consistent and stable temperature.

An optimal stable temperature allows the heating elements to operate at their best. Thus, they improve print quality.

What Is a PID Tune?

3D printers work through heating components. The printer hot end and the heated bed remain the two most recognizable printer heating elements.

The heat produced by the printer nozzle and the heated bed needs new PID values whenever it becomes unstable and inconsistent.

As such, you’re called upon to use the PID technology to stabilize the heating element temperature.

PID technology uses an algorithm involving a proportional-integral-derivative of the heating element temperature.

So, What Does the P, I, D Mean?

Proportion (P) stands for the ratio of the actual temperature to that of the requested temperature.

Integral (I) stands for the error value noted upon comparing the actual and expected temperatures of the heating process.

Finally, Derivative (D) denotes the speed at which the actual temperature rises above or below the requested temperature.

How Does PID Heating Work?

The machine control panel of the firmware accepts the P, I, and D values. In other words, you can manipulate the three values to PID autotune start.

The algorithm calculates how your printer shall heat the heating element.

How Do I Calibrate My PID for 3D Printing?

If your 3D printer experiences many variations in the hot end and heated bed printing temperatures, your prints end up with artifacts, lines, and other similar challenges.

The best way of preventing temperature variations of the heating elements is to conduct PID autotuning.

Still, most printers have software such as Marlin that includes the “PID autotune finished” feature. It is a tab that indicates or signals the completion of the PID tuning.

If you’re calibrating printers manually, follow a software command that helps you to PID tune the hot-end temperature.

The firmware sends G-code commands that enable the machine to achieve the same results you’ll have received from an automated printer.

If you’re using the original Prusa printers, you need to ascertain the version you own by going to the help menu. It will be best if you frequently update your printer software.

Before you begin calibrating your printer, be sure to raise your hot end slightly ten centimeters away from the print bed. Then go to the main menu.

Next, move to select the PID calibration tab. Select the hot end temperature value that you use more frequently in your Printing.

Subsequently, the printer will run the PID calibration automatically. At the end of the process, the nozzle temperature will rise and fall a few times, generally in five cycles.

After the five cycles of hot-end temperature variations, the temperatures stabilize, and at this point, you’re good to start 3D Printing.

How Do You PID Tune a 3D Printer Bed?

To calibrate or PID tune a 3D printer bed, use software to send G-code commands to your printer firmware. OctoPrint and Pronterface are software capable of transmitting G-codes to printers.

Firstly, run the M303 command in the software’s G-code terminal. It allows it to get to your printer firmware.

Secondly, get and enter the calibrated values, then save PID settings. PID autotuning and saving the settings eliminate the need for repeating PID auto-tuning.

The terminal gives a PID autotune start alert when running the command. The sign signifies the beginning of the process that will run for a few minutes before it concludes.

PID Values

• M303 represents the primary command that triggers the PID autotune calibration
• S60 stands for the required heat bed temperature
• C10 denotes the number of cycles the heating element temperature fluctuates before eventually stabilizing.
• U1 stands for automatic replacement of the existing heat bed temperatures with the new values.
• At the end of the autotune process, save the new values. The printer firmware retains the PID settings for subsequent use.

How Do You Use PID Autotune?

You should start the autotuning process using the start/stop signals. Let the process run for a period to complete the frequency response experiment.

Subsequently, transfer the tuned values from the block to your PID controller.

Step by Step Process to Start the Auto-tuning Process

• Enter a hysteresis depending on the amount of noise coming from the PV. You can start from 1.0%.
• Set your printer mode to autotuning
• Adjustment of the SP should lead to a PID tune value that is slightly higher or lower than the PV
• Then select the control method that can either be PI or PID
• Pick the “Start tuning” tab

How Long Does PID Autotune Take?

If you presuppose that your delay time is four minutes, the PID tuner will take 20 minutes to tune. Also, a delay time of more than a few minutes in other tuning methods makes the PID tuner take long, even hours, to PID autotune.

However, Marlin’s autotune takes approximately five minutes, even if you engage it for six cycles. Check your LCD screen; it shows temperatures soaring up past the setpoint, then gradually falling back.

It will fluctuate a couple of times. In the end, it enjoys accurate constants for the P, I, and D numbers in the equation. These constants are typically denoted as KP, KI, and KD constants.

How Do You PID Tune-in Marlin?

To PID tune in, Marlin, firstly confirm your printer’s version of Marlin. We have Marlin versions like Marlin 1. X or 2X1. It ensures you use the right or compatible commands for the specific version.

Connect your G-Code terminal with the printer’s firmware terminal. Be sure to get the correct PID commands from your firmware company.

Choose the Header you intend to PID, for example, E1. Follow it up by choosing the number of heating cycles. Heating cycles refer to the number of times the printer heats the heating element to and down from the target value.

PID Tuning Marlin Hot End

• Enter M303 E for heater number and C for the number of cycles before sending using the G-code terminal
• Then wait for the terminal to complete the set number of cycles
• Enter the M301 command, then put the P(KP value), I(KI value), and D(KDvalue), representing constant values, and send the command.
• Finally, send the M500 command to save and retain your new values in the firmware’s mainboard.

PID Tuning Marlin Heated Bed

• Connect the G-code terminal to your firmware terminal
• Identify Marlin the version
• Enter E-1 for Marlin 1.x and EBED for Marlin 2.X
• Decide on the number of cycles; the more cycles you choose, the more accurate and the longer the PID tuning time
• Enter M303 E, S, and C, which represents the PID autotune commands
• Once the terminal finishes cycling, put in the P, I, and D values that the printer generated. The values will be constants KP, KI, and KD
• Enter the M304 command, then put the generated constant values
• Finally, send the M500 command to save and store the new settings in the printer’s mainboard

Ender 3 PID Settings

You can autotune your Ender 3 with Pronterface software. It is software that allows you to control your printer from your personal computer (PC). You only need to have a PC and a USB cable to flash your firmware.

To PID tune Ender 3, open the software. The main menu will offer you an area to pick your PORT and Baud Rates.

Notably, Ender 3 has a Baud Rate of 115200 unless stated otherwise. So choose the option for your printer and connect.

Use the terminal window to send the M303 E0, S225, and C10 to start the PID tuning. It will go for ten cycles before it completes tuning.

It will display the “PID Autotune Finished” alert on completion of PID tuning. Then pick the generated PID values you should use.

Use the M301 command to input the new values followed by the M500 command to save and store the new PID settings.

Octoprint PID Tuning

• The Octoprint PID tune process is similar to other software PID tuning but with minor variations. Open the Octoprint after connecting the G-code to the printer firmware terminal.
• Go to the terminal tab.
• Check the suppress message checkboxes.
• Input M303, E0, E230, C10 to begin autotuning
• The buffer will push out the suppressed messages
• After completion of the process, enter the new values into your printer
• Save and store new PID settings using the M500 command

Conclusion

Achieving high 3D print quality remains the goal of every 3D printer user. However, the extruder nozzle and the heated bed’s sudden temperature changes are detrimental to better print quality.

Therefore PID tuning comes in handy to regulate and stabilize the hot end and the heat bed temperature.

Michael Brooks is the founder of M3DZone.com. He sees a very bright future for 3D printing that's why his mission is to try and make this easy for everyone. Discover your hidden talent and creativity. You can follow here: Facebook, Twitter & Pinterest.