PCB milling machines??

[Michael Buchstaller]

>When I enquired about one of them in the late 1980's, the least 
>expensive one was around $10k. Not unreasonable if you're a business, 
>a bit pricey for a hobbyist...

I have such a milling machine from a company in Austria; i think they
are called "Step Four". This one was not so expensive (DM 4500;
approx. $2500), and it does a good job. It attaches to the PC´s
parallel port and comes with a simple DOS program which can
read HPGL files. They do have a web site at http://www.step-four.at/

I once tried to make a PCB with this machine, but it was a nightmare.
You have to use a very tiny drill bit so you can make the small cuts
between IC pins, and it takes endless hours to remove the copper
from the board :-(
When i  compare this to how simple it is to etch a board.... normally
it takes me approx. half an hour from the printout to the finished etched
board, and then a few minutes to drill the holes.

But what is really great with this milling machine: I do use it to make the
front panels for my modular. The machine engraves the letters and
symbols, and also does create all holes, even irreglular shaped ones
and rectangular ones; and they look GREAT !
(have you ever made a cutout for a meter or a sliding pot with a
jigsaw and been pissed off by the result ? then this is for you)
If you want, you could see a sample module at
http://www.buchi.de/m100/vcoB.CFM
It does not look that good, because the panel is old and scratched,
but i have also done the front panel for the Tubemaster, a black
anodized 19" aluminium plate wih now shining silver letters - GORGEOUS !
sorry, there is no picture of this unit on the net avialable, but i have
scanned a part of another panel i have made the same way, at
http://www.buchi.de/PanelTest.gif
it´s approx. 1 meg size, but i i reduce the size, one cannot see how the
letters are milled.



-Michael Buchstaller