Homebrew PCBs

There's a PDF which I found interesting and don't recall being mentioned
on the list:

  http://rick.sparber.org/electronics/el.htm

  Convection Etching of a Circuit Board
  http://rick.sparber.org/electronics/ce.pdf

in which a clear glass tray is filled with etchant, a lamp is placed
underneath to illuminate and heat it, and the single-sided PCB is
floated on the surface of the etchant.

The ferric chloride and citric acid etchant I use would be too opaque to
use the illumination aspect of this technique, but it might be useful in
terms of warming and promoting gentle circulation of etchant.

  FeCl + citric acid = Edinburgh Etch; HCl is transparent?
  http://tech.groups.yahoo.com/group/Homebrew_PCBs/message/30540
  2012-08-23

  - Robin