Reliable GNU gcode generator?


I am new to the CNC thing. Usually I am designing with rhino

and I am looking for a gnu gcode generator where I can put stls in

an configure my tool to mill with.

Is there some software alike Slic3r for cnc?


kind regards


Well Estlcam is not on a gnu license nor free

You can run it for free. I’ve not seen a gnu cam application worth using yet.

You’re looking for CAM software, which will help you search.

I haven’t looked too closely at it. I’ve seen Linux CNC (and MachineKit, which is a fork). bCNC can do some simple CAM. Simpler than STL is CAM using dxf or svg files. I’m really not sure what FOSS can do 3D CAM.

I use Linux on my machines and I’m surprised I haven’t really fought to learn this. If you find something, let me know. I use EstlCAM in wine.

Found this list and looked into a couple of programs.


I checked two of them out on win7.

Both look complex and have CAD included. I cant really tell if they are good but I think they are worth a look. They are both open Source and free for non-commercial use.

I have to try out gCAD3D. Didn’t know about that one.

I started with HeeksCAD/CAM. It was no picnic getting it to compile on Debian jessie. Once I upgraded to stretch it doesn’t work any more and I don’t get it to compile. Although I haven’t given it much time as HeeksCAD is OK for simple things, but I never warmed up to it. Sometimes it just hangs for a minute or two when things get more complex. And I never managed to go beyond 2.5d milling although it supposedly should support this.

At the moment I use FreeCAD and pycam for 3d milling STL files. Although both are far from perfect.

FreeCAD: You really have to use the git repository to get something useable. And you need some luck to end up with a useable version when you make a new compile. I now have two build directories. In one I have a known good version. If I want to try out new features I use the other build directory. Then I always have a working version. Some things are a bit rough, but if it works I really enjoy working with FreeCAD. I like the constraint based construction. You probably need to read some tutorials to get started. But it’s not as bad as it feels at the beginning.

pycam: I use the 0.5 version that comes with Debian. I had too many problems with the 0.6 version from github. The path from 0.5 are sometimes far from optimal, but it get’s the job done even if it takes a bit longer to mill.

Other than that I use KiCAD, PCB2GCode, Camotics, bCNC and GRBL.

KiCAD: Used to generate PCBs. Very nice software.

PCB2GCode: Nice command line program to generate GCode from the Gerber files KiCAD (and most PCB Software) produces. I also compile that one myself. I don’t remember what was wrong with the version in the Debian package (maybe it’s even fixed because I last tried it on jessie).

Camotics (formerly known as OpenSCAM (who came up with THAT name :-)): Simulates your machine so you can check if the produced GCode is OK.

bCNC (on a RaspberryPi 3 at the MPCNC): Nice GCode sender with some additional functionality: Autoleveling (for PCB milling), Z probing, Toolchange macros (nothing beats semi-automatic tool changes :-)).

GRBL: CNC software for the Arduino UNO. Very nice with different coordinate systems (machine coordinates, several workpiece coordinates). At the moment I’m using a cheap CNC shield (for < $2). But I’m in the process of changing from the DRV8825 drivers to stand alone TB6560 drivers to get more torque and want to mill my own CNC shield in the near to medium future (That’s more or less trivial as it’s kind of just a break-out board to get better connectors for the wires from the TB6560, spindle speed control and from the endstops.)

That’s my toolchain with completely free software (not just free of charge). I hope it helps a bit.


It’s GNU and Linux source code is provided… I haven’t tried it much yet. I did try to install it in Ubuntu just now for fun but had some problems with PyQt5.

I’m fine running it in Windows, so I’m not sure I’ll bother.

Whether it adds anything to the features available in other FOSS offerings I’m not sure. It does claim to support drag knives if that is of interest. I presume that’s just for corner moves, but haven’t checked.

I don’t believe it supports STL if that’s an issue.