Many people wonder how they should turn off their 3D printers. I decided to write an article that answers this question so people can learn the proper method to turn their 3D printers off, along with some unique methods to turn it off remotely.
Keep on reading to find out more.
What Should You Do After a 3D Print?
Here are two things you should do after a 3D print:
Allow the 3D printer to cool down before you turn it off
Clean the bed if it’s messy
Allow the 3D Printer to Cool Down Before You Turn it Off
After a 3D print, you should wait for the hot end to cool down to a certain temperature of about 60°C and below, and then you can turn off the 3D printer.
If you turn off your 3D printer right after completing a print, the fan will stop immediately while the hot end is still hot. This can result in the heat travelling up the hotend which can creep up to the filament and cause it to soften and jam the pathway.
One user recommended waiting for the hot end temperature to drop below 90°C before switching off the printer.
This temperature is safe enough as most plastics do not melt at this temperature, but you should still be careful and allow the hot end to cool down to 60°C or below before powering off the 3D printer.
Most people recommend not switching the 3D printer off immediately after a 3D print. Some people implement a script in their G-Code to automatically turn off after the hotend has cooled down.
Clean the Bed if it’s Messy
If your bed is quite dirty, it can be worth giving it a clean, but it’s not always necessary after your 3D prints. In some cases, you can have left over filament that gets stuck to the bed, or remnants of dust and dirt.
You can clean your bed by heating up the bed to around 30-40°C, spraying some isopropyl alcohol or water on it and cleaning it with a microfiber cloth or paper towels. Isopropyl alcohol is a better cleaner than water and it evaporates easier.
Using your scraper can be a good idea for cleaning up tough remnants on the print bed.
One user said he starts cleaning his 3D printer’s bed by scraping it lightly with a metal scraper, then wiping it with a damp cloth to remove any glue from it.
Another user said that he had gotten his PEI sheet used for more than 500 hours of total print time to look new by wiping it with 99% isopropyl alcohol sprayed tissue.
Hobby Hoarder has a great video about cleaning glue from 3D printer’s bed.
How to Power On an Ender 3 (Pro, V2)
To power on an Ender 3, simply connect the power cable to the PSU (power supply unit), plug it in, and then flip the switch on the power supply unit.
One user had issues turning on his Ender 3 Pro after plugging it in. It turned out that the PSU was set to the wrong voltage.
The issue was solved when the PSU was set to the right voltage of his location. Here are some voltage ratings for some countries:
United States – 120 volts
United Kingdom – 230 volts
Canada – 120 volts
France – 230 volts
Italy – 230 volts
Another user had problems powering on their Ender 3 V2 after switching the PSU (power supply unit) to the correct voltage. The printer beeps and the LCD screen is powered on with a 1.0.2 firmware message when the USB cable is connected.
It was eventually figured out that the manufacturer swapped the earth and power pins at the power socket. The pins were swapped back, and the Ender 3 started to power on correctly.
How to Turn Off 3D Printer After Print
To turn off a 3D printer after printing, you can simply flip the power switch on the printer after the hot end has cooled down to around 60°C. A 3D printer can also be turned off automatically after a print.
Here are some guides from Thingiverse on how you can automatically turn off an Ender 3 after a 3D print:
A user figured out a way to turn off his 3D printer by using a relay on the 120V going into the PSU of his printer. This PSU control Octoprint plug-in is then used to flip the relay switch to turn off the 3D printer.
The plug-in can also be configured to wait for the printer to drop to a certain temperature before it automatically flips the relay switch to turn off the printer.
Another user has had good results using an IoT Power Relay connected with a Raspberry Pi to control a 3D printer and a lamp using the OctoPrint software to turn on and off his 3D printer. When a print job finishes, he can power off the printer and the lamp from wherever he is to save power.
G-Codes can also be designed to turn off the 3D printer after it has cooled down to a certain temperature.
Check out this video below by CNC kitchen to learn G-codes for 3D printing.
The recommended hardware on the OctoPrint official website for installation of OctoPrint software is the Raspberry Pi 3B, 3B+, 4B, or Zero 2.
The Raspberry Pi Zero and Zero W are not recommended since severe performance issues have been observed in them when used with OctoPrint.
Connect the power cord to the relay module
Install OctoPrint on the Raspberry Pi board
Connect the relay module to the Raspberry Pi board
Set up the OctoPrint software in a browser
Connect the Power Cord to the Relay Module
To connect the power cord to the relay module:
Take the power cord that you use for your 3D printer, unplug it, and then remove part of the insulation at one end by making a small cut into it. Make sure you don’t cut too deeply so the wires don’t get damaged.
Cut the black wire in the middle if it is a US plug or the brown wire if it is a European plug.
Remove the insulation at the ends of the brown or black wire cut in the middle in step 2 above.
Connect the ends to the holes on the relay board.
This process is shown in the video further down called How to Turn Your 3D Printer On/Off Using OctoPrint.
It’s recommended to use an IoT Relay, an enclosed high-power power relay, for the remote switch set up, which takes the place of a relay module.
It is fully assembled and ready to use. It also includes surge suppression, debouncing, and a safety breaker to protect the connected board from faults.
One user has his 3D printer in an enclosure, which he controls with OctoPrint through the Raspberry Pi GPIO pins and the IoT power relay already mentioned.
He recommends plugging the Raspberry Pi board into one socket of the IoT power relay board to protect it from electric surges.
The IoT relay also has a neat design without a bunch of wires hanging out of it compared to a cheap relay making it safer to use.
Install OctoPrint on the Raspberry Pi Board
To install OctoPrint on the Raspberry Pi board, it is recommended to get at least a 16-gigabyte MicroSD card to have more space for 3D model storage and G-code files.
Download the OctoPrint software from the official website and install it on the Raspberry Pi board. You should set up a password to control access to your OctoPrint account.
Crosslink has a great video that details how to install OctoPrint on the Raspberry Pi.
Connect the Relay to the Raspberry Pi Board
Using a jumper wire, connect the relay module to the 5V, ground, and any GPIO pin on the Raspberry Pi board.
It is recommended to connect the jumper wires to pins 3, 4, and 6 as these pins are next to one another, making them comfortable to work with.
Set Up the OctoPrint Software in a Browser
Open your web browser and log into your OctoPrint account using the IP address of the Raspberry Pi board. To set up the OctoPrint software for your 3D printer:
Go to Settings > Plugin Manager > Search for the PSU Control plugin and install it.
The PSU control is now in the settings tab. Click on it and change the switching method to GPIO
Set the GPIO to board
Set the GPIO pin number to the GPIO pin connected on the Raspberry Pi board
Check out the video below for how you can turn on off your 3D printer remotely.
One user figured out a way to power off their 3D printer remotely using a Home Assistant installed in their house. The Agara plug-in is set up to run through ZigBee, which switches off the 3D printer when the printer is done printing.
The plug-in monitors the power usage of the 3D printer and powers it down through a smart plug when the power usage is less than 10 watts for more than 30 seconds.
The 3D printer is idle when its power usage is less than 10 watts for more than 10 seconds, according to the user.
Michael Dwamena is the founder of 3D Printerly, a platform dedicated to simplifying 3D printing for hobbyists and professionals alike. Owns over 20 3D printers (filament and resin) and has plenty experience 3D printing. Michael has authored over 900 articles, helping millions navigate the exciting world of 3D printing.
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