At 06:57 AM 6/23/2011, you wrote:
> > Of course you could use a UV laser diode to expose photoresist or use a=
 LD
> > to ablate a resist coating, and subsequently do a chemical etch. You co=
uld
> > use the laser diode for light while the CNC mill is engraving. You coul=
d
> > sell the 1W laser diode on eBay and use the=20
> proceeds to get a professionally
> > made PCB.. lots of possibilities.
>
>Hot air or other preheat, using LASER as the final straw?

They use ~100=B0C preheat for soldering, which gains you maybe 80=B0C, but
that's not a big percentage of temperature delta you need to get up to
the boiling point of copper (1080=B0C). Actually, precooling might be an no=
vel
idea, to preserve the laminate. Ablating from LN2 temperature (77K) would
only require ~20% more power than from room temperature.

Best regards,

Spehro Pefhany --"it's the network..."            "The Journey is the rewar=
d"
speff@interlog.com             Info for manufacturers: http://www.trexon.co=
m
Embedded software/hardware/analog  Info for designers:  http://www.speff.co=
m




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