The KNK Force runs a unique distribution of Linux, which comes pre-installed with Cutter Command Center, or C3.

07-01-2022 Update: A few clients have reported issues with the Win32DiskImager. Luckily, the Raspberry Pi Foundation have released their own disk utility  Raspberry Pi Imager. It's a great alternative, and can be used on both PC and Mac. Click here to download the Raspberry Pi Imager

To write a fresh installation, you’ll need to install an operating system image on the SD card. This will require the use of a computer with an SD card reader.

Downloading the Image

You can download an early version of the image hereOnce you have downloaded the ZIP, extract it to get the .img which we’ll write to your SD card.

Writing the image to your SD card


  • Insert the SD card into your SD card reader and check which drive letter was assigned. You can easily see the drive letter, such as G, by looking in the left column of Windows Explorer. You can use the SD card slot if you have one or a cheap SD adapter in a USB port.
  • Download the Win32DiskImager utility from the Sourceforge Project page as a zip file; you can run this from a USB drive.
  • Extract the executable from the zip file and run the Win32DiskImager utility; you may need to run this as administrator. Right-click on the file and then select run as administrator.
  • Select the image file you extracted earlier.
  • Select the drive letter of the SD card in the device box. Be careful to select the correct drive; if you get the wrong one, you can destroy the data on your computer’s hard disk! If you use an SD card slot on your computer and can’t see the drive in the Win32DiskImager window, try using an external SD adapter.
  • Click Write and wait for the write to complete.
  • Exit the imager and eject the SD card.



  • Connect the SD card reader with the SD card inside. Note that you must format as FAT32.
  • From the Apple menu, choose “About This Mac” then click on “More info…”; if you are using Mac OS X 10.8.x Mountain Lion or newer, then click on “System Report”.
  • Click on “USB” (or “Card Reader” if using a built-in SD card reader) then search for your SD card in the upper-right section of the window. Click on it, then search for the BSD name in the lower-right section; it will look something like diskn where n is a number (for example, disk4). Make sure you take a note of this number.
  • Unmount the partition so that you will be allowed to overwrite the disk. To do this, open Disk Utility and unmount it; do not eject it, or you will have to reconnect it. Note that on Mac OS X 10.8.x Mountain Lion, “Verify Disk” (before unmounting) will display the BSD name as /dev/disk1s1 or similar, allowing you to skip the previous two steps.
  • From the terminal, run the following command:sudo dd bs=1m if=path_of_your_image.img of=/dev/rdiskn
    Remember to replace n with the number that you noted before!
    • If this command fails, try using disk instead of rdisk:sudo dd bs=1m if=path_of_your_image.img of=/dev/diskn

Updating C3

Once you’ve finished installing the OS image and placed the SD card back into the KNK Force, you’ll need to update to the latest version of C3. At the time of writing this post, we’re currently on version 0.5.15. If your KNK Force is on an earlier firmware version, the update should update both software and firmware.

You can update by going to the Status page, or by entering your Force’s IP address followed by /update. For example: