Hey well ive been working on CNC for the last two years of highschool currently in grade 12 and have gone past what the teacher knows so ive gone on to trying to do some simple 3D cuts but the only problem is the models I want cut came from blender or 3ds Max so there meshes and not solids or surfaces is there a way to cut them using free open source software we do have MasterCam X and MasterCam 9 that I can use but it doesn't like meshes also what tool path type would I use since all be cutting in wood and alum it can't just jab in and cut like it did with foam it needs to cut all the stock from the top down leaving nothing but the model left ? It is a 3 axis and I know it won't be perfect but it will do

About the mesh objects: I know that some CAM programs will only accept mesh objects, so meshes can definitely be used. I don't know the process that would be required though. I would suspect the biggest hurdle would be to export your 3D Studio Max drawings into an AutoCAD compatible format (DXF or DWG probably, maybe IGES?). If 3D Studio Max has that ability built in you're probably golden.

Another option would be to find a 3rd party program that can convert between a format that 3DS Max can export and a format that your CAM program can import. There are websites that convert files (I've never used them though, so I don't know how well they work).
Here's one: http://www.zamzar.com/ (whether it does any 3D files, much less the ones you need, is beyond me.
There are also a bunch of freeware apps out there that will convert one file format to another. They typically follow this naming scheme: <EXT1>2<EXT2>. I wouldn't be surprised if you could find a program called "3ds2dwg" if you looked hard enough.

Almost all, if not every, CAM program out there will have a "step down" parameter that you can set (usually for each "MOP" ("Milling OPeration" I think)). This setting will tell the CAM software how to automatically produce the multiple levels of milling that you need. I've seen this feature called "waterline milling" on at least one CAM program.

I have the perfect video in mind that shows a machine cutting a 3D part from aluminum by taking many very shallow cuts, but for the life of me I cannot find it. (I looked for at least a half-hour.)
Hey, I stumbled upon it again... here it is: http://www.youtube.com/watch?v=mcUqS9t0Yyw

It's been a while since I posted... but here is a link to a free 5x plugin, I've played with it, but don't have much of a need for it. Meshcam is another that will machine straight from a mesh file. It's not free , but the 30 day demo may get you thru your project.

Whoa, the man with the plan!

Bump...

I found the video I referred to in post #2. Here's the link again...
http://www.youtube.com/watch?v=mcUqS9t0Yyw