PCB milling machines and shorts...

[Harry Bissell]

Yeah: I like a BIG capacitor charged up to 50 volts or so (more if you have
"big brass ones")... Tie them to the board... Its like the Trauma Center....
Nurse, we're losing him... Paddles... Clear... BLAM !!!!   :^)  Harry (semi OT)
Bissell

jhaible wrote:

> > > I was paging through Electronic Design and saw a couple of ads for
> desktop
> > > PCB milling machines which basically goes from Gerber to drilled PCB by
> > > milling away copper and drilling holes.  Has anybody used these or know
> > > anything about them.
>
> Terrible stuff, if you're asking me.
> I know because I spent a lot of time looking for shorts on boards that were
> done that way.
> You always have the problem of adjusting the height of the tool, the board
> never being
> perfectly planar or even resonating at certain rotation speed of the tool.
> So you end up
> either removing too much copper - or the contrary. We used to look for
> shorts that were
> caused by copper connections that were too tiny to see them - decide which
> traces are
> shorted, and then burn away the connection with a strong current source.
> A mere nightmare.
>
> JH.