Homebrew PCBs

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