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?

Check if your CAD does a dual line or two line or some such.

This becomes a whole procedure operation in CAD.

Draw your parts as you normally would.

Then move to a new layer and make sure snaps to all layers are on and
that lines being drawn on all layers is off. ie: you can snap to a
point on a different layer, but all the lines you draw from here on
out are only on this layer.

Then determine where you want to start cutting and snap to that
point, then snap to the next point along the cut path.

you ABSOULTLY MUST do each and every part IN ORDER, that means a
straight line to a curve to a straight line, is re-drawn in that
order.

With the double lines, you get to define the width or your tool
offset.

With redrawing things IN CUT ORDER, then ACE will also follow your
line order.

SAVE the file often.

go back and delete your trace line and leave your cut line.

save often.

I will sometimes save at different points as file-a and file-b so I
have snap shots of the work.

>
> 3. I haven't yet tried the Ace Converter; how should one set start

and

> direction of cut?
>

If you do the CAD file as above, you already did the cut direction.
ACE strictly and only follows the lines you drew in the order you
drew them. That is why you need to pick the start of cut and draw
every object in cut order.

> 4. Since my applications are just hobby type, are there some low

cost

> CAD systems which you would recommend?

As Caudlet says, cut files from CAD are featureless. no ramps, no
feed rates, and unless you do the dual line above with a second
smaller line, you get one cut path and not a rough cut followed by a
finish cut. Using the above, you rough with a 3/8 bit and finish
with a 1/2 or some such. Not pretty, but functional.

I am surprised that he did not recommend SheetCAM as the software
that does a professional way of bridging the gap between drawing and
your final tool path g-code.
http://groups.yahoo.com/group/sheetcam


AND, learn G-Code. it WILL be of benefit to you from here on out. I
recommend people only program in G-code when they get started to get
that background experience. IT will go really fast once you learn a
few functions. You'll be glad you did.


Dave