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Subject: Re: Gerber- Pads-PLT-Surprise

From: Alan Marconett KM6VV <KM6VV@...>
Date: 2002-04-24

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