Re: Could it be this easy?

--- In CAD_CAM_EDM_DRO@yahoogroups.com, <testfly@a...> wrote:

>
> Let me tell you what I want to do and someone tell me if it can be

done.

>
> I want to open say MSpaint or paint shop pro and use the drawing

tools in

> there to just click and draw a 2D shape. Say a square. Then I would

like to

> print that as I can using my printer. Simple and easy right? Sure

it is...

> However what I would really like to do is to be able to save that

drawing

> and then feed it to my CNC table and have it move my router so it

cuts out

> the shape rather then put it on paper. I could set the drawing tool

to mark

> a 1/4" line on my paper and if the cutting bit was 1/4" then WAL-LA

I have a

> simple way to cut simple shapes.
>
> Can this be done or should I wake up from my little dream here?
> Using XP and win 98. Be nice If I could do things up in XP on my

computer

> and then run the cnc with laptop (win 98).
>
> Thanks in advance,
> Troy

First you need to understand the difference between a bitmap painting
program like MS Paint or PSP and a vector (line) drawing program like
a CAD or Illustration program. A paint program draws in dots at the
resolution you select (DPI). A CNC tool does not normally cut
in "dots" (photo engraving excluded) but in continuous lines. For
drawing in lines you need to use a CAD or illustration tool. Corel
and Adobe Illustrator are the most popular illustration tools while
AutoCAD and TurboCad are true CAD tools for drawing things with
precision. If your intent is to do "artistic" type cuts or sign
work, then Corel is a good choice and older versions (Pick Ver 9 if
you have a choice) are available cheap. In Corel you can draw
freehand or use their square and ellipse tools along with the
hundreds of fonts they include to design what you want. Once it's
done you can: Print to any Windows printer or save (export) the
vector format to HPGL or DXF formats for a piece of software that
will help you define the toolpaths and then another software piece
called a controller to interface to your CNC machine to actually move
the motors.

Given you want to use Windows for everything, the simplest
combination is to 1.) Draw it to scale in Corel and Export it as an
HPGL (plotter) file. 2.) Use XP based MACH2 (www.artofcnc.ca) to
import the HPGL and select a few basic tool functions and send it to
your CNC machine. That will work for simple 2D designs where you are
cutting contours.

You will probably quickly see the value of another piece of software
called the CAM where you take the basic drawing and are able to
define the way the toolpath is done including things like: inside and
outside cuts, tool offset (cutting on the edge of the tool rather the
center)feedrates, lead-ins and lead-outs, etc etc and then to spitout
a correct machine control file in industry standard g-code.

If you want to do router work or milling you need more complex
options like mult-pass depth cutting, step milling, spiral or
circular cutouts, finish pass cuts and other complex moves. Some
2.5D and most 3D cutting needs to be defined in specialized software
that can get expensive as the features increase.

For doing 2D and simple 2.5D cuts, one of the list guys is working on
a piece of software called SheetCam (www.sheetcam.com) that shows
real promise and will be priced for the home hobby market.

Suggestion: buy, or borrow an older copy of CorelDraw ver 9 or later
(they also have a paint program called Corel PhotoPaint which you
don't need) and use it to draw some simple shapes. Download the free
eval copy of MACH2 (needs to run on WIN2000 or XP) and the free Beta
copy of SheetCam. Now you have all the tools you need to do some
pretty neat stuff and even without a CNC machine, you can run the
visual simulation in MACH2 to watch you creations "cut".

Use your paint programs to edit photos and printout pictures for the
family ;-). Later when you want to convert a bitmap into a vector
drawing and cut it on your machine then ring us back for the way to
do that but don't start out trying to machine a picture
(bitmap)....you will get real frustrated.

Tom C