Re: CAD Questions

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "jcc3inc" <jccinc@o...> wrote:

>
> Gentlemen:
>
> I am not very familiar with CAD. I made a shape with a series of
> lines and arc segments (36 total)using TurboCad (Ver 6) and
> DeltaCad. To handle the cutter comp, it took me maybe 30 minutes
> with DeltaCad and the finished product seemed OK. With TurboCad, I
> couldn't get the offset correct on arcs, but spent a lot more

time.

> My questions are:
>
> 1.Does one have to offset *each* segment, then add the corner radii
> in order to generate the compensated shape, or should the CAD do it
> more or less automatically once the direction and starting point

are

> set?
>
> 2. Once the basic shape is completed, how long should it take to
> generate the compensated shape?
>
> 3. I haven't yet tried the Ace Conveter; how should one set start

and

> direction of cut?
>
> 4. Since my applications are just hobby type, are there some low

cost

> CAD systems which you would recommend?
>
> Thanks in advance,
> Jack C.

Jack. You are missing one of the important parts of the CNC
equation. Even as a hobby it gets tedious rooting around down in the
code if your goal is to make things with your machine. Things like
tool type, offset type (inside, outside), pocketing, feedrates. lead-
ins, etc are better done in a CAM program. Some of the hybrid
programs have both CAD and CAM features. There are also low cost
pure CAM programs that will let you graphically define your toolpaths
and give you precise control over the cutting process and spit out G-
code faster than you can blink your eyes! Take a look at the 150.00
(free demo) of SheetCAM (www.sheetcam.com) for 2D and 2.5D shapes.

For CAD you need to define what kind of "things" you are making with
your machine. If it's pure mechanical parts a true CAD program is
best. If you want to do decorative cuts with complex artwork and use
TTF fonts then you might want to consider an Illustration/Drawing
package like CorelDraw or Illustrator.

I know the above choices are not free but compared to what your
choices were just a year ago it's close.

If you use your CAD/Drawing program to do the basic drawing and your
CAM program to define the tool paths and generate the g-code then
your software Controller program will spin your motors and make your
part.

You should be able to draw a simple shape (lines, arcs, circles,
squares, stars, polylines, polygons in less than 10 minutes, export
and define the toolpaths (another 10 minutes) and be making chips (or
sawdust) in less time it took to do your original simple drawing.