On Sun, 28 Oct 2012 11:11:15 -0400, you wrote:
>On Sun, 28 Oct 2012 05:38:53 -0000, you wrote:
>
>>Thanks.
>>
>>When you say 'bubble air through it' you mean like w/ a fish tank air pump w/ those 1 way valves?
>
>Yes, exactly that. You want a plastic air stone, not a porous stone,
>because the acid attacks that stone. Not sure about this plastic, but
>there are kinds of plastic (nylon, for instance) that are not as acid
>resistant as you'd like. Avoid stainless steel, too.
>
>>Do I know how much air I need based off the color and if so, what color am I looking for? In the past I had some weak acid and it turned teal blue but this stuff is staying bright lime green.
>
>A decent air pump should be fine. More air is better than not. It
>does several things, one is oxygenate the etchant, the other is keep
>it moving so fresh etchant hits the boards.
>
>The bright lime green sounds a bit odd, because most of my stuff is
>blue/green, not lime. The ratio I used was 4x peroxide (the 30 vol or
>3% stuff) to 1x muriatic acid (38%, IIRC). The opaque olive green is
>when it needs more HCL, I think. Adding peroxide to the dark green
>stuff turned it blue, as I remember.
>
>
I made a bubbler for use in a plastic storage bottle. Started with 12" of 1/2"
CPVC tubing and two CPVC end caps. I first drilled a bunch of #60 holes
around the tubing from 5/8" to 1 1/2" from one end. I then pressed a
cap on the perforated end; no glue. My WalMart air pump had dual outputs,
so I used a "T" to feed both into the pipe by drilling a hole in the other cap
just large enough to press the "T" into after applying universal PVC/CPVC
glue. I then pressed the cap onto the open end of the pipe. No glue on
the cap to pipe joint here either. Two pieces of plastic tubing between the
"T" and the air pump and it was ready to go.
I can stick the thing into a bottle and get lots of bubbles. I've used this
for over two years with no sign of deteriation.
Keith Bowers WB4LSJ- Thomasville, NC