Re: [CAD_CAM_EDM_DRO] Laser specs ?

turbulatordude wrote:

>Hi all,
>
>Can anyone advise how one can figure just what laser wavelenghts are
>needed to cut different things ?
>
>I seem to remember someone saying that one type of laser would not cut
>glass, but another would.
>
>
>

I seriously doubt you could cut glass with a laser. It would either
have to be
insanely slow, to allow the glass to cool after every pulse, or it would
go REALLY
fast, directing the progress of the crack by heating ahead of the leader.

>I am interested in what it would take to cut copper on a PCB, and not
>cut the fiberglass. if that is possible.
>
>

Not practical. Copper has an extremely high heat conductivity, the
highest of
metals. It would take huge amounts of energy, as the shiny surface of
the metal
would also reflect much of the incident light, even well into the IR
wavelengths.
So, you're kind of double-damned with copper. I think you could do it
with hundreds
of Watts at 10.6 um (CO2), but the rate of cutting would still be really
slow.
And, having to cut wide enough gaps between traces for solderability
would take
many times longer than just cutting a single micron-wide slit.

Jon