Hi mate!
unfortunately, politicians want us incapable, we must not be intimidated by a simple search

...I give you an approximate list of the steps necessary to install linuxcnc on LMDE3, but remember you may need some extra precautions to make it work properly, personally I installed it only in simulation mode and I can not tell if it works 100% reliably on a work machine.
1- Install LMD3 that is based on Debian Stretch.
LMD3
2- Download and run Linuxcnc Debian Stretch Live DVD.
LCNC Stretch
3- Go to "/etc/apt/sources.list.d" into the live CD and copy linuxcnc.list file to your Linuxmint Debian Edition-3 OS sources.list.d folder.
Code:
deb http://linuxcnc.org/ stretch base
deb-src http://linuxcnc.org/ stretch base
deb http://linuxcnc.org/ stretch 2.7-uspace
deb-src http://linuxcnc.org/ stretch 2.7-uspace
deb http://buildbot.linuxcnc.org/ stretch 2.7-rtpreempt
deb-src http://buildbot.linuxcnc.org/ stretch 2.7-rtpreempt
4- Reboot your PC.
5- Open a terminal and add the key for Wheezy from linuxcnc doc. page
getting LinuxCNC
Code:
sudo apt-key adv --keyserver hkp://keys.gnupg.net --recv-key 3cb9fd148f374fef
6- Bring the PC up to date
Code:
sudo apt-get update
sudo apt-get dist-upgrade
7- Open Synaptic, search for linuxcnc package, utilities and dependencies The RT kernel should be among the recommended dependencies, otherwise search the kernel, linux header and image with Synaptic, check all of them for install. (you can download it from the first post). Sim mode doesn't require a RT kernel.
8- Reboot...
9- Donwload and install Grubcustomizer:
Code:
sudo apt install build-essential libssl-dev cmake libgtkmm-3.0-dev gettext libarchive-dev
wget https://launchpad.net/grub-customizer/5.0/5.0.8/+download/grub-customizer_5.0.8.tar.gz
tar xfv grub-customizer_*
cd grub-customizer-*
cmake . && make -j9
sudo make install
10- Open Grub Customizer and choose your installed kernel as your first booting choice.
11- Reboot...
12- Kindly tell us if the installation on your work machine was successful to share it and help others.
Floris