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Subject: RE: [Homebrew_PCBs] thoughts on electric paint sprayer for spray etching

From: "Rick Sparber" <rgsparber@...>
Date: 2013-01-29

Swamp coolers are common here in Arizona but never saw one until I came
here.

Rick

-----Original Message-----
From: Homebrew_PCBs@yahoogroups.com [mailto:Homebrew_PCBs@yahoogroups.com]
On Behalf Of Jeff Heiss
Sent: Tuesday, January 29, 2013 3:19 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: RE: [Homebrew_PCBs] thoughts on electric paint sprayer for spray
etching

I checked Walmart for immersion pump and swamp pump but did not see any
listed. Could you give a reference to one online?

Jeff

-----Original Message-----
From: Randall Morgan <rmorgan62@...>
Sent: Tuesday, January 29, 2013 3:25 PM
To: Homebrew_PCBs@yahoogroups.com
Subject: Re: [Homebrew_PCBs] thoughts on electric paint sprayer for spray
etching

A "Swamp" cooler is a type of air conditioning device that works by the
evaporation process to cool air. They are very simple. Water is pumped to
the top of panels usually filled with burlap or hemp fibers. The water runs
down through the fibers soaking them. Air is then pulled through the fiber
panels and blown into the room. As the air is pulled through the fibers it
picks up maximum humidity. Once released into the room the air evaporates
its excess humidity to conform with current atmospheric conditions. As the
water is released from the air it takes heat with it. Air itself is a very
poor storage medium for heat and stores most of its heat in the moisture
contained in it.

Swamp pumps can be purchased at most hardware stores and even walmart.



On Tue, Jan 29, 2013 at 7:26 AM, Jeff Heiss <jeff.heiss@...> wrote:

> ∗∗
>
>
> Todd, I like your ideas. What is a "swamp" cooler pump? I am not
> familiar with drip irrigation spray heads. Are they like mister nozzles
for gardens?
>
> Jeff
>
>
> -----Original Message-----
> From: Todd F. Carney k7tfc@...>
> Sent: Tuesday, January 29, 2013 2:35 AM
> To: Homebrew_PCBs@yahoogroups.com
> Subject: Re: [Homebrew_PCBs] thoughts on electric paint sprayer for
> spray etching
>
> On Mon, Jan 28, 2013 at 8:47 PM, Jeff jeff.heiss@...> wrote:
> >
> > What are opinions on using an electric paint sprayer to spray etch a
> > board? Could an electric sprayer be modified to run etchant so it
> > can resist corroding? Would the spray pattern, droplet size, and
> > spray force
> be
> > acceptable?
> >
>
> Jeff,
>
> Just to clarify, do you mean for the sprayer to resist corrosion? If
> you use ferric chloride, that doesn't seem likely. Maybe not even a
> persulfate etchant.
>
> I used to use shop-built bench-top (actually, lab-sink-top)
> spray-based etching machine that was pretty much all plastic. It
> consisted of an open-top plastic tank, an immersion heater (from a
> small hot-water heater), an immersion pump from a "swamp" cooler, and
> sprayers made of PVC pipe, and a holder that clamped the board to be
> etched in a frame. The sprayers hit the board evenly on both sides at
> once. The little spray heads were made for drip-irrigation use. We
> placed a sheet of plexiglass on top to contain overspray and so we
> could monitor the etching. We used persulfate etchant in it (which we
> left in it until it had to be replaced) so it was not a source of
> staining-or-toxic ferric chloride. I don't know how or if that damn
> stuff would work in such a machine. We never used it. I don't think any
professional or commercial pcb outfits use it either.
>
> These days, a darkroom tray works for the one or two boards I might
> make in a month. I use home-made peroxide-muriatic-salt etchant. I
> just hand agitate the tray. I was toying with the idea of making a
> motorized rocking agitator, but then I came to my senses.
>
> 73,
>
> Todd
>
> ----------------------------------------------------------
> K7TFC / Medford, Oregon, USA / CN82ni / UTC-8
> ----------------------------------------------------------
> QRP (CW & SSB) / EmComm / SOTA / Homebrew / Design
>
> [Non-text portions of this message have been removed]
>
> [Non-text portions of this message have been removed]
>
>
>



--
If you ask me if it can be done. The answer is YES, it can always be done.
The correct questions however are... What will it cost, and how long will it
take?


[Non-text portions of this message have been removed]



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