Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, Reginald Beardsley <pulaskite@...> wrote:
>
I'm not worried about the stiffness of the wire as it will be supported for all but a very short (i.e. < 0.1") distance. In the absence of actual data, I've assumed that surface tension would keep the wire tip approximately hemispherical, so by controlling the voltage I can limit the cutting area to the wire diameter.
>

Hmm -- that .1" of wire is going to burn up pretty quickly. (Remember that EDM always consumes the electrode as part of the process.) Will you be feeding wire to replace it? How will you control its length? How will you transfer the electrical power to the wire? I'm sure these are issues that can be dealt with, but they will add another layer of complexity to your project.

As for limiting the cutting area to the wire diameter -- I can't say with respect to something as thin as the copper layer on PCB; perhaps you will be able to do that. Don't be surprised, however, if you wind up getting a .005" cut from your .003" wire.