The control computer has been set up as a dual boot machine. This gives me the ability to use the machine using the free Mach3 control software. I use this mainly for testing, direct input projects and very small projects. When more lines of gcode are required, I can start the machine in Ubuntu and use the Linux CNC control software.
Mach3 is one of the most used control packages available. It is simple to set iup and to use. Mach3 is released in two versions: a Lockdown version, and a Development version. The Lockdown is a stable, static release recommended for new users. The Development version contains developing features and is released so people can obtain new and untested features and capabilities. The free version is intended for demonstration and is limited to 500 lines of gcode.
Linux CNC is an open source control system. By comparison it has a more difficult learning curve but has the advantage that it is not limited in the number of gcode lines. The latest version of Linux CNC runs on Ubuntu 10.4 Lucid Lynx. This version of Linux was chosen because of the commitment of support in the long term.
For testing and simulating gcode, I use Planet CNC. Planet CNC control software in it's own right. It is my intention to upgrade my machine at some time in the future to the planet CNC system. The full system consists of hardware and software that uses the USB link to communicate with the computer. The hardware runs the gcode interpreter.
This should have long term benefit and provide far more accurate timing for the motors. The software can be downloaded free of charge and used for simulation of your gcode. The software is easy to use and is high quality.
For the generation of gcode, I have a licensed copy of Cambam. This is an affordable package that has good features and is easy to use. The software can be downloaded and it will provide 40 free and fully functional evaluation sessions. This is adequate to test and evaluate the software. It is also a far better method than providing a time limited version as you can have life interfere with you plans and this will still not limit your evaluation period. A free version is also available.
In the beginning of my experimentation, I had a lot of difficulty with engraving. Most CAD applications specify the font and the CAM programs change this font to their default font. Furthermore it is difficult to get the gcode to remain within the boundaries of the font. The Cambam forum does have stick fonts available and these do help for smaller engraving. After a lot of experimentation, I found a delightful little application, Deskengrave, which will allow you to save and script using any font as a DXF file.
This allows you to insert the actual script into your main design and to generate the gcode with the correct tool offsets. I use this program to generate the script and copy and paste the text directly in to my design. In the design is can be scaled to the exact size you require. More importantly it is a case of "What you see is what you get".
GIMP is the GNU Image Manipulation Program. It is a freely distributed piece of software for such tasks as photo retouching, image composition and image authoring. GIMP is a very powerful program and thus has a step learning curve. It is a great tool for taking jpeg files and converting the picture to a trace for machining. It is possible to save the trace as a standard vecture graphics file (SVG) but I still have to learn the process. As a tool to prepare a picture for further processing it is very effective.
Inkscape is another very worthy tool for the conversion of pictures into a bit trace and has the advantage that a script is available to save the trace as a DXF file. The script, however, does not work with the latest version of Inkscape. It is possible to export directly to a less popular version of DXF and then it can be converted to R12 version with the help of Draftsight. The R12 version of DXF file is most reliably recognised file when used with CAM programs.
Inkscape is also important as scripts are now available for the creation of gcode directly from Inkscape. A lot of work is being done with regard to this aspect and it is predicted that picture will be exported as 3D gcode in the future. I personally have very little experience with Inkscape, but will invest the time to understand it at a later date.
Wintopo is a very good program to convert the path of a picture, once a edge detect has been performed, into a vector drawing. Wintopo will directly save the vector file into a DXF format. The advantage of Wintopo is that the trace is presented as a single line. Inkscape trace is a dual line.
After each picture is traced a large amount of work is required to edit and ensure the trace is of good quality to machine. Wintopo is available in as a free program with the option of purchasing a more professional version.
GMax is a free 3D modeling program. It was intended for game enthusiasts to be able to create their own scene and characters. It's potential has been spotted and scripts have been written to make this potential available to CNC enthusiasts. Gmax and the CNC toolkit are a very worthy programs for both drawing 3D entities and for generating the gcode to machine the resulting project.
A lot of work has been done to make the program suitable for 5 and 6 axis machines. I have successfully created a few design but need to invest a lot more time into understanding the program to be able to use it to it's full potential. A visit to the CNC toolkit website is essential.