--- In
Homebrew_PCBs@yahoogroups.com, "Stefan Trethan"
<stefan_trethan@g...> wrote:
Hi Stefan ( sorry about misspelling your name before -- must be brain
fade induced by the summer heat ),
> Just this minute i did a small experiment. I built the very simple
supply
> shown in the link you gave for light edm work.
> Connected it up and used a manually moved pointy steel screw as
electrode.
>
> i can definitely see that work is all i have to say. With this you
could
> draw your PCBs by hand. Of course i got mighty rough edges with
moving the
> electrode by hand, but i could mill slots in the copper with no
problems.
The higher pulse rate and lower current power supply yields a MUCH
smoother cut.
> I kind of feared it might mill away all copper around tiny residual
> particles, so that they remain there, but it seems it cleans the
copper
> clear off in neat circles.
> I'm pretty much convinced it will work for me in a cnc setup.
> I can even see it useful as a "electric milling wand" to do touchup
work
> or cutting sripboard or even manually cutting very simple boards. It
is
> much faster and cleaner than scratching, as it doesn't affect the
epoxy.
> The water is a drawback though.
In what way? It keeps the elctrode from burning and washes out the
particles.
> Very rewarding experiment, recommended for everyone.
>
> (Here the URL again:
> <http://cscott.net/Projects/FabClass/final/edesign1.html#schematic>
"A
> simple circuit", stay under 30V if you want to touch the eletrode.).
>
>
> I really need to see pictures. pleeeaaasssee ;-)
>
>
I'll get right on it after the 4th. Promise ;D
Curt