Instructions on how to set up the Klipper firmware

What is Klipper?

Klipper is a 3D printer firmware that runs on a general purpose Linux computer (a Raspberry Pi in this case) as opposed to the microcontroller of the printer. The advantage of this is that the complex inverse kinematic calculations of delta printers can be processed on the Raspberry Pi, which has way more computational horsepower compared to the 32-bit microcontroller in the printer. This way, all the microcontroller has to handle are the movement commands (ex. move stepper_a 10 steps) as well as heating commands (ex. heat extruder to 200 degrees). This results in a much smoother operation of the printer.

Another advantage of Klipper is that you don't have to recompile and flash the printer firmware every time you change something in the configuration file like you do in the Marlin firmware. You can even edit the configuration file on the web interface and hit a button to reset the printer and instantly load the new configuration. This makes the tuning process much more efficient.

It's also highly configurable. Here are some of the cool things you can do with it:

• You can set it up to run multiple boards on a single printer (if you have a ton of steppers and/or extruders)
• You can run multiple printers from one Raspberry Pi and control them all from a single web interface
• You can set up a printer farm by running a ton of printers on a powerful Linux PC

Use this online README as a reference since the troubleshooting section is constantly updated, or git pull frequently.

Klipper Firmware for the FLSUN QQ-S Pro Delta Printer

Due to the lack of information about how to configure Klipper for this particular printer, I have decided to create this repository that contains everything you need to get Klipper up and running on the FLSUN QQ-S Pro delta 3D printer as well as an in-depth tutorial. I've also added a short guide on how to install a filament sensor and/or a BL Touch on the printer.

The QQ-S Pro uses a board very similar to the MKS Robin Mini, but shares the same pinout as the MKS Robin Nano V1.

How to Connect an End-stop Switch Style Filament Sensor

Open this link and connect the filament sensor to 'MT_DET1' and use the printer_qqs(Filament Sensor).cfg file.

Note that this is a highly recommended upgrade because the stock FLSUN Highspeed board has an empty slot available for it. You also don't have the problem where you have to connect it to the Raspberry Pi when running the printer from a web interface, like you do in Marlin. It's a simple upgrade, just plug it in and you're good to go. No soldering or removing of components required.

How to Connect a BL Touch

Note that it is usually not recommended to use an offset probe like the BL Touch on a delta printer due to effector tilt. However, this can be compensated for by running Klipper's enhanced delta calibration routine. It's a very involved process, but if you're installing a BL Touch, I'm sure that's not a problem for you.

I've only included this here because I was able to get it to work just as well as the stock probe, but the only advantage that it has is that you don't have to remove the probe everytime you either auto-level the bed or run a calibration routine.

Open this link for the pin reference on the board.

1. Print this hotend mount with the BL Touch attachment and install it in the printer.
2. Remove the WiFi Module
3. Switch the jumper pin from 3.3V to 5V (located near the top right of the WiFi module - from perspective of picture)
4. Connect:
   • Orange wire -> IO0-PA8
   • Brown wire -> GND
   • Red wire -> 3.3V
   • White wire -> Z- (PA11)
   • Black wire -> Z- (GND)
5. Use the corresponding printer_qqs(BL_touch).cfg file

How to Install the Klipper Ecosystem

There are 4 different types of configurations for the QQ-S Pro in the configurations folder:

1. QQ-S Pro Stock
2. QQ-S Pro with Filament Sensor
3. QQ-S Pro with BL Touch
4. QQ-S Pro with BL Touch and Filament Sensor

They are all the same, with some sections commented out according to your desired configuration. I've inlcuded four of them so that you can just simply copy and paste it without having to comment sections out, which can lead to errors if done incorrectly.

Hardware you will need:

1. Raspberry Pi w/ SD Card
2. (optional) Webcam
3. QQ-S Pro Delta Printer
4. Computer (PC, Mac, Linux)

Software you will need:

1. MainsailOS Operating System for Raspberry Pi (This OS already comes with all of the software pre-configured below)
2. Klipper firmware for printer (.bin file)
3. Klipper client for Raspberry Pi
4. Web interface (OctoPrint, Mainsail, fluidd)
5. Klipper API - Moonraker (if using Mainsail or fluidd)
6. Kiauh (Klipper Insallation and Update Helper) - will be used to install all the required software on the Raspberry Pi

Step 1 - Setting up the Raspberry Pi

The heart of Klipper is the Raspberry Pi, which will be running both the firmware and the web interface through which we control the printer. These are the steps to set up the Pi. This guide is going to go over how to configure the Mainsail or fluidd web interface as OctoPrint isn't as optimized for Klipper. Although it works just fine with the OctoKlipper plugin, both Mainsail and fluidd were developed for Klipper (fluidd is a fork of Mainsail so they're pretty similar). They both have a better interface in my opinion.

However, if you are hellbent on using OctoPrint or need to use its massive plugin library, you need to download OctoPi and install the OctoKlipper plugin to get it working but I'm not going to cover the OctoPrint setup since it's already covered in the original Klipper installation page. Step 2 and Step 4 are still relevant though.

1. Download the latest release of the MainsailOS
   • unzip the .img file from your download
   • insert an 8GB or larger SD card into your computer and do not format it, if you do, the flashing process might fail
   • use BalenaEtcher to write the .img to an 8GB or larger SD card. This will overwrite all the data on your card (eject and remove the SD card when done)
   • if you are not going to be using WiFi, insert the SD card into the Pi, hook it up to an ethernet cable, turn it on, and continue to step 2
   • if you are going to be using WiFi, plug the SD card back into your computer, open the 'boot' folder, and find the file named mainsailos-wpa-supplicant.txt
   • open the file with a plain text editor like SublimeText, other text editors such as TextEdit(Mac) or Notepad(Windows) have been known to mess the configuration up.
   • Find this block of code:

   ## WPA/WPA2 secured
   #network={
   #  ssid="put SSID here"
   #  psk="put password here"
   #}
   

   • Uncomment the last 4 lines by deleting the # in front of them
     • replace put SSID here with the name of your WiFi network (don't delete the double quotes)
     • replace put password here with the password of your WiFi network (also don't delete the double quotes)

• Save the file to the SD card, eject it, and insert it into the Pi

• Default username: pi

• Default password: password (or raspberry)

2. Boot up the Pi and wait a few seconds and open up https://mainsailos.local.
   • You should see the Mainsail interface on your browser
   • If you don't, your Pi is probably not connected to the Wifi Network. You either:
     • entered your network information wrong
     • Have a RaspberryPi 3+ and above and are using the onboard WiFi, in which case you need to open up mainsailos-wpa-supplicant.txt and uncomment your country for it to work
3. ssh into it from your computer: ssh pi@mainsailos.local
4. Navigate into the klipper_config folder cd klipper_config
5. Create a printer configuration file: touch printer.cfg
6. (optional) If you want to use fluidd instead of Mainsail you will need to install kiauh. git clone https://github.com/th33xitus/kiauh.git
7. (optional) Then navigate to the kiauh directory: cd ../kiauh
8. (optional) Run kiauh: ./kiauh.sh
9. (optional) Remove Mainsail, it is possible to run both fluidd and Mainsail.
10. (optional) Install fluidd - make sure to install the macros when it prompts you
11. (optional) Quit Kiauh
12. Exit your ssh session: exit

Refresh the web-page if you installed fluidd and you should see the new interface

Step 2 - Installing the firmware on the printer

This firmware is the same for all QQ-S Pro printers. The configuration is done on the Raspberry Pi.

Precompiled Version

I've included a pre-compiled version of the printer firmware in the precompiled_firmware folder that should work for all QQ-S Pro printers.

1. Drag this file into the root directory of the SD card of your printer, insert it, and power it on. It is the same process as flashing Marlin or any other firmware on the QQ-S Pro.

Uncompiled Version

If you'd rather compile it yourself or my precompiled version is not working for some reason, this is what you need to do:

1. ssh into your Raspberry Pi: ssh pi@mainsailos.local
2. Navigate to the klipper directory: cd klipper
3. Type: make menuconfig and select these settings:

• Enable extra low-level configuration options
  • Micro-controller Architecture (STMicroelectronics STM32)
  • Processor model (STM32F103)
  • Bootloader offset (28KiB bootloader)
  • Clock Reference (8 MHz crystal)
  • Communication interface (Serial (on USART3 PB11/PB10))
• (250000) Baud rate for serial port

4. Press q to quit and y to save your settings
5. Type make to compile the firmware
6. Next, navigate to the scripts folder: cd scripts
7. Run: ./update_mks_robin.py ../out/klipper.bin ../out/robin_mini.bin

• this will rename the firmware file from 'klipper.bin' to 'robin_mini.bin' and save it to the out directory

8. Navigate to the out directory and verify that the file 'robin_mini.bin' exists: cd ../out then ls
9. Disconnect from your Pi: exit
10. Download the 'robin_mini.bin' file from the Raspberry Pi to your computer using sftp: sftp pi@mainsailos.local then cd klipper/out then get robin_mini.bin

• this will download 'robin_mini.bin' to whichever directory you've issued the sftp command from

11. Drag this file into the root directory of the SD card of your printer, insert it, and power it on. It is the same process as flashing Marlin or any other firmware on the QQ-S Pro.

Step 3 - Connecting the Printer to the Raspberry Pi

1. Open the web interface http://mainsailos.local in your browser

2. Plug in the printer to one of your Raspberry Pi's USB ports

3. ssh into your Raspberry Pi: ssh pi@mainsailos.local

4. Find out which serial port your printer is connected to: ls /dev/serial/by-id/* and copy the output

5. Open up the printer.cfg file on your browser:

• Mainsail: in the Settings/Machine tab on the bottom left
• fluidd: in the Configure tab on the top right

6. Once in the printer.cfg file, delete everything and copy the contents of the desired config file from the configuration folder of this repository

7. Set your printers serial port:

• find the [mcu] section
• delete the path after serial: and paste your output from step 4

8. Press the 'Save & Restart' button, if successful you should hear the printer beep and take a couple seconds to connect

• if your printer is not connecting, try pressing the 'firmware restart' button or typing FIRMWARE_RESTART in the console

9. Test the connection by homing your printer or typing G28 in the console.

Step 4 - Calibrating the printer

1. The first thing we need to do is connect the z-probe to the effector (the autolevel switch), attach any print surface material (masking tape, etc.), then heat the bed up to 50 degrees since materials expand with heat.

• If using a BL Touch, follow this guide to calculate the X and Y offset of the probe before continuing.

2. First you need to calculate the 'z_offset' by opening up the web-interface console and typing: PROBE_CALIBRATE

• After the probe stops, remove it then do the paper test (place a piece of paper under the nozzle)

• Type: TESTZ Z=-<value> to decrease Z-height and TESTZ Z=+<value> to increase it, where <value> is the amount in mm by which to decrease or increase the Z-height (usually 0.05 or 0.01 if close to the bed) so that there is just a little friction between the nozzle and paper.

• when you are satisfied with the Z-height, type ACCEPT and then SAVE_CONFIG

• edit your printer.cfg, any existing 'z_offset' will have been commented out in the [probe] section, and a line with the correct value will have been inserted at the bottom of the file

• add the correct 'z_offset' value into your [probe] section

• make sure that horizontal_move_z in the [delta_calibrate] section, is set to a value 5-10mm higher than the z_offset we just calculated

• save the file and restart

• home the printer and re-attach the probe

3. Then type DELTA_CALIBRATE. Once this is done type: SAVE_CONFIG to save the settings.

• This will get a decent calibration for your printer, good enough to print well. However if you really want to optimize the calibration for your specific printer, run the Enhanced Delta Calibration which requires you to print an object, measure it with digital calipers, and input the values in the console.

4. Bed mesh leveling is enabled in all the config files, so after setting the Z-offset, type BED_MESH_CALIBRATE in the console then SAVE_CONFIG when finished.

   • If using an offset probe (like a BL Touch) you might get an error 'move out of range' because the probe offset causes the print head to move outside the range of the print bed. If this happens, try decreasing the 'mesh_radius' or offsetting the 'mesh_origin' in the config file.

5. Remove the probe

6. Copy START_PRINT and paste it in the start g-code of your slicer.

7. Copy END_PRINT and paste it in the end g-code of your slicer.

• Both these macros can be found in the config file, so paste any start and end g-code originally found in the slicer underneath the gcode: line in both [gcode_macro START_PRINT] and [gcode_macro END_PRINT], so the only thing that should be in your slicer is START_PRINT and END_PRINT. This way, if you need to add or delete any gcode commands, they can all be done in the config file without having to reslice the model.

Step 5 - Printing

1. Load some gcode and start a print

2. Both Mainsail and fluidd allow you to adjust the z-offset while printing if the calibration didn't get it quite right. If you do this, this z-offset value (which is shown on screen) is reset after every print. In order to make that value permanent you have to:

• go back to [gcode_macro START_PRINT] and uncomment the line: SET_GCODE_OFFSET Z_ADJUST=-0.1 MOVE=1 by removing the # in front of it.

• Then replace -0.1 with the z-offset value you got during printing. This way, it will load your specific offset every time you start a print.

• The END_PRINT macro is equally important, because it resets the offset value after every print. If you don't add it to your slicer, Klipper will add your offset values after every print. Ex. print1 offset=0.1, print2, offset=0.2,... until you restart the printer.

Documentation and Further Tuning

Here is the Klipper documentation where you can find more info about configuring Klipper. These config files are a great starting point and will get you up and printing. However, everyones printer is slightly different and will need to be calibrated and tuned further. Klipper has a lot of really cool features like pressure advance and input shaping. Take the time to read through the documentation and understand Klippers features; there's so many. The config reference section is probably the most useful reference while tuning.

Troubleshooting

1. Why does my bed mesh look really weird?

   • Either your printer is not calibrated properly or your probe is not accurate enough

   • Try running PROBE_ACCURACY with your Z-probe attached and if you get a range value greater than 0.025 mm, your probe is not accurate enough to use mesh leveling and you have to delete your mesh profile in the web interface.

   • If You get a range value less than 0.025 mm, then you need to run the Enhanced Delta Calibration

   • You can look at these examples of bed errors to see if they look like your bed mesh. If so then running the Delta Calibration should help.

2. Why is my extruder temperature reading way off?

   • The wrong temperature sensor is probably set in the [extruder] section of the config file. The stock thermistor of the QQ-S Pro is sensor_type: EPCOS 100K B57560G104. Check out the documentation for all supported temperature sensors.

3. Why is my probe not working?

   • This was my mistake! I forgot to invert the logic of the probe pin. I've updtaed the configuration files fix this issue. To fix:

     • Navigate to the [probe] section of the config file and change pin: PA11 to pin: !PA11.

4. Why is my printer timing out when I home it?

   • It's probably caused by the [idle_timeout] and timeout: 360 lines in the config. Try commenting them out. I've made this change in the config files as well
   • Try switching the USB port the printer is connected to on the Pi

5. Why is my printer going backwards when I home it?

   • This is probably due to the use of different stepper drivers, it can be fixed by adding a ! in front of each dir_pin in the [stepper] section.

   • For example:

   [stepper_a]
   dir_pin: !PE2
   

   • Do this for all 3 steppers.