Re: Hobbiests Strike Again

Hello from a new member

Andrew Werby wrote:

> Message: 3
> Date: Thu, 28 Oct 1999 05:57:48 -0700
> From: "Dan Mauch" <dmauch@...>
> Subject: Re: Hobbiests Strike Again
>
>
>I looked at his PCB . What impressed me is that he is milling his traces.
>Dan
>
>[Even if he isn't, people keep asking me how they can do this. Is there a
>program out there (or a combination of programs, even) that simplifies this
>process so someone can go from a picture of a pc board to a g-code plot
>file? It would be nice if the hole-drilling were automated as well- am I
>dreaming? Does anybody out there cut pc boards with a mill, or is everybody
>convinced that etching is the way to go?]

I have been working on this same idea the program I have been
using is the EAGLE Layout Editor from CadSoft [http://www.cadsoftusa.com/%5d
it has a schematic editor,board layout,autorouter and toolpath output
there are both Linux & windows versions available so you can run it on an EMC
box for on the spot edits. It can be downloaded and run as a
non-comercial/freeware/demo for hobby users ,the board size is limited to
about 3.5"x4.2" and 2 signal layers - plenty big enough for a
modular machine control unit (one of my current projects)
once installed you can edit the device definitions file - eagle.def
to output any flavor of RS-274D that you want ,or use HPGL if youve got a plotter.
Also on their download page under user files are several scripts that will generate
a trace isolation toolpath for milling or engraving your board look for
mill2.ulp ,mill_drill.ulp ,etc.The board layout editor can also be used for
simple 2d cad with G-code output,using a difrent layer for each tool.
the way I have been making small PCBs is to chuck a Sharpie(R) marker
in a locked spindle (or plotter) and draw the traces directly onto the copper
then etch as usual ,the ultra fine point pens have a line width of about
.7mm and the thicker markers can be blunted to about 1/8" width for power traces
just be sure to draw slowly enough to leave a good thick resist layer or
the lines will etch thru (my first plotted board had all the pads but no
traces.connect the dots anyone?) a set of good technical drafting or
plotter pens should go down to .25mm wide if you dont mind the price ("light"
crashes jump from 50cents to 8$ ,"heavy" ones stay about the same)
to hold the board down I use a some strips of thin double stick tape on a
sacrificial backing board.
I wonder if you could draw the traces onto a non-conductive surface with one
of those conductive ink pens,then use an elecroless tin dip plating solution
to build them up to a good thickness? Has anyone tried this?