I always check what Sourceforge has to offer http://sourceforge.net/search/?q=cnc , I don't know how good these programs are and I haven't the time to play with them but it's worth a shot if you're on a budget or have no budget at all :)

'Generic CAM' looks interesting you can define up to 9 axis' http://sourceforge.net/projects/genericcam/

Cheers

I would say with many options to look at, the main thing you want to pay attention to when deciding (Well first is can it create the toolpath I want), is that the program can output the gcode for your mach3 to read... They all arent created equal...

So, is the code output customizable and to what degree? (You could ignore this part if you are capable of hand editing)

CamBam will do a great job with 2D dxf's and stl files from MoI.
I use it for mould work quite a lot.

It doesn't have 4th axis capability, but there is another program called CNCWrapper that will convert either the X or Y coordinates to rotary. Note that it isn't a TRUE representation of rotary like you'd get with dedicated software, but it's still very good.

CamBam is fully functional with 40 trials before it reverts to only producing ~500 lines of gcode, so if you leave it minimised to the Taskbar you've got plenty of time to get the feel of how it works.

Martin.

Thanks for all your answers! I understand a little bit more now!

the new inkscape support Gcode ;)
http://www.cnc-club.ru/forum/viewtopic.php?f=33&t=35&start=20