Re: [CAD_CAM_EDM_DRO] Re: EMC and Taig w/ MicroProto and DeskCNC

William Perun Sr wrote:

>Anders, thanks for the reply. Your response triggered a thought.
>Are CNC hobby milling users, using EMC2 to CALL the G-code files
>from VS-3D, or DeskCNC, or MACH 3. And then they write subfunctions
>in EMC2 to enable the example engraving application I described.
>Thus creating a Fanuc capability with hobby CNC interpreter or CAM
>software?
>
>

You can't use more than one of Mach, DeskCNC, or EMC at the same time.
There's no way to use the current EMC2 interpreter from within Mach or
DeskCNC.

>I guess I still don't know if Mach 3 or DeskCNC can do Parametric
>Programming.
>

I'm not sure about that. I believe that either one allows you to write
custom code in Visual Basic, or to call DLL functions from your own
code. I'm not sure how this integrates with the motion controller in
either.

> And I guess DeskCNC is also a kind of CAD CAM software
>because you can write G-code in it, thus designing a part to be
>machined. Of course it would have to be something simple,
>especially for me.
>
>

Unless there's a text editor, I don't think you can do CAD/CAM with
DeskCNC. I know it can load bitmap or DXF files, and directly machine
them based on some parameters you supply. I don't know what facilities
there are in DeskCNC for creating pockets and the like. I imagine
that's more of a Bobcad / Vector function (though Fred can certainly
chime in with the correct answer). Mach has no built-in CAD or CAM
functions, though there is the new LazyCam program that's included (I
don't know how it integrates with the Mach UI). EMC2 has filters
available for DXF, STL, and image file types as well (in fact, any image
that can be read by ImageMagick can be machined as a height map, which
includes roughly 90 image formats). There are also some scripts for
directly exporting Eagle PC Boards for milling, and for G-code path
length optimiaztion. They're not as easy to use at this point, but
we're getting there.

>I guess I don't understand why someone would use EMC2 instead of
>DeskCNC or MACH 3. I guess DeskCNC and MACH 3 do all kinds of
>administrative tasks (Windows programming, stepping motor control,
>machining geometry (pockets, ... ) optimization, and many things I
>don't even have a clue about. How does EMC2 do these behind the
>scenes tasks?
>
>

Well, I guess it depends on what operating system you're using, how much
you want to spend, and what hardware you want to use. DeskCNC works
only with their step generator board, as far as I know. Mach works with
several kinds of hardware for generic I/O, and can now (or soon) use the
G-Rex for step generation. As far as I know, only the parallel port
(and soon the G-Rex) can be used for step output with Mach. EMC2
supports several types of hardware, including parallel port step
generation (like Mach), parallel, ISA, or PCI connected step generator
cards, and analog servo control cards (and multiple kinds of hardware
simultaneously). Note that EMC is the only controller (for less than
roughly $5000) that does true closed loop motor control.

If you're running Windows, then you should choose Mach or DeskCNC (there
are others as well, I believe). There's also TurboCNC for DOS. If you
want to run Linux, or you want to use sometihng other than the parallel
port / G-Rex / DeskCNC controller, then use EMC.

>Again thanks for your reply.
>
>Bill Perun
>
>

Another point - it looks like think you're confusing three separate
parts of computer aided design and manufacturing. These are the steps
to go from concept to finished part:
1) Design (CAD): This can be a sketch on a napkin, or something created
in a 3D solid modeling program. The end result of this is usually
called "geometry" - it's a representation of what you want the part to
look like, but it generally doesn't include data about how to make the part.
2) Translation (CAM): You can open up notepad (or equivalent) and write
G-code, you can use a post-processor like MasterCAM, or anything in
between. In general, this step combines the design data (geometry) with
material data (making a part out of plastic is much different from
making it from Titanium) and process data (machining, laser sintering,
stereolithography, etc. are different methods of creating the part, and
need different data).
3) Machine Control: This is the program that actually controls the
motors (and lasers, waterjets ...) on your machine. They usually use
G-Code to describe the toolpath. Here's where the constraints of the
particular machine are applied to the engineering and process data, to
create the final part. (This is also the on-topic part, for this list ;) )

Some of this confusion probably stems from the rudimentary CAD/CAM
programs that are included with machine controller software ;)

- Steve