> I had bought a low-cost etch tank that used a pump to move the
> etchant over a ramp of sorts, where the pcb was placed.
Pulsar (formerly DynaArt) sold an etch tank that used two
fish tank pumps to force etchant over a molded plexiglas sheet
to create a laminar flow. You could put the PCB copper side
up on the plexiglas for one sided etching, or use standoffs
to hold it just above the plexiglass to etch both sides.
I had one for a while but couldn't find a pump that would
put up with the etchant (ammonium persulfate). Whatever the
answer is, the agitator or impeller needs to be isolated
from the drive source, and ideally it fits into a variety
of tank sizes and shapes to accomodate one's varied applications.
Mark B.
Albuquerque, NM