Alan,
As you combine traces they get puffy and they start to look
like cartoons rather than traces. Years ago (I am 50)each trace was
a seperate pad trace pad. Then companies that made TVs started
increasing the width of the traces. After awhile the boards had
larger and larger traces. Large ground traces. I think this was to
save on acid during etching. Then when digital hit the traces got
thinner again. Long thin traces riding over barren sections of
boards. I have always tried to leave as much copper on the board as
possible. I had acid poop out on me once because I tried to remove
too much copper. I learned a valuable lesson that day.
John
--- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...> wrote:
> Hi John,
>
> Thanks for the reference to TCI! Generates Gerber 274X, but I can
> extract the apertures by hand (my code doesn't do that... yet). Is
this
> the test file you were speaking of? Looks short enough. When I get
> time, I'll run it through my program. I don't have the elliptical
pads,
> 'tho.
>
> Yes, These programs should form a common base for our efforts. And
TCI
> might be a little simpler then Eagle, which I still haven't found
time
> to learn (I managed to generate Gerber files of their DemoR1 board,
> 'tho).
>
> OK, I see that now. Ground pads. Makes sense. Your boards look
like
> cartoons? How so?
>
> Yes, simple is best. But I often like to explore the "blue sky",
for
> self edification, mostly.
>
> Alan KM6VV
>
>
> crankorgan wrote:
> >
> > Hi Alan,
> > Please note most people in the group will be using Kcam-
> > TurboCad or Eagle. You seem to have a handle on the situation. The
> > TCI program I got in the files section here I beleive. The
program is
> > in French? After you draw the circuit board. Save it! Then hit
> > Gerber! A Gerber file of the same name will appear in the
directory
> > where you save the board file.
> >
> > You mentioned circles that don't meet in my DXF file.
Sounds
> > like a Ground Pad. On boards I sell to the public I outline a
ground
> > connection for parts or wire on three sides. My new boards look
like
> > cartoons. After I get the board working I go back and combine
traces
> > with only a common border. Since a board is stuffed from the
component
> > side I am taking out unnecessary cuts. My first boards were done
this
> > way. I can get two large boards per bit. Milling time is also cut
in
> > half.
> >
> > Just remember I try to keep things cheap and simple.
> >
> > John
> >
> > --- In Homebrew_PCBs@y..., Alan Marconett KM6VV <KM6VV@a...>
wrote:
> > > Hi again John,
> > >
> > > Not to beat a point to death (or belittle a fine product), but
> > FREEWARE
> > > KCam might not be the best example of generating Gcode from a
Gerber
> > > file! And as you say, it's generating EIGHT SIDES (like you
do),
> > not a
> > > SINGLE ARC, as I've said can be done.
> > >
> > > My program (actually just a FUNCTION in my controller program)
is
> > still
> > > quite LIMITED in what it can do with a Gerber file
> > (not "automatic" by
> > > any means), but I'd LOVE a new sample of Gerber of "real work".
> > I've
> > > been able to do most of "DEMO1R" file that they supply.
> > >
> > > I was not able to get KCam to read my Gerber files, so I know
> > little of
> > > KCam.
> > >
> > > Yes, the "Traveling Salesman Problem" affects all such
machining,
> > board
> > > stuffing, etc. You are lucky in that you can "hand optimize"
the
> > order
> > > of your cuts. I'll just import into Vector CAD/CAM, and let
Vector
> > do
> > > it for me. Or I can select the closed "trace cuts" in the
order I
> > want
> > > (the trace cuts themselves will already be ordered properly).
> > >
> > > That is until I decide that TSP's an interesting problem to
solve,
> > and
> > > apply it to my own code! No rush!
> > >
> > > I'd love to examine the Eagle (TCI3?) and/or Gerber files for
your
> > test,
> > > if you wouldn't mind. What is TCI3? TurboCad?? Is your file
> > RS274X or
> > > RS274D? 'X' has a "header" in the file with all the aperture
data,
> > > while 'D' usually has an additional file (wheel file) with the
> > > apertures. Can you supply?
> > >
> > > Thanks for your contributions to this list!
> > >
> > > Alan KM6VV
> > >
> > >
> > > crankorgan wrote:
> > > >
> > > > Hi Group,
> > > > I made a test pcb in TCI3. I saved it as a Gerber
file. I
> > > > then put it in KCam. The round pads became eight sided shapes.
> > > > Forty-two pads became over 1000 lines of code. The Gcode drew
the
> > pads
> > > > in the same order I drew them in TCI3. So I suspect if you
don't
> > want
> > > > your machine to spend more time traveling than cutting you
better
> > > > have a plan.
> > > > I will admit I have very little experence with
Gerber.
> > But I
> > > > get the feeling the "Traveling Salesman Sydrome" is hiding
there
> > > > also. Plotting out a PCBoard with a good PLT file is much
faster
> > than
> > > > a GCode file run on a homemade PCBMill. A Sherline or Taig
> > running at
> > > > 10,000 rpm can only cut circuit boards at 5" per minute. So
do a
> > test
> > > > board before it is too late!
> > > >
> > > > John