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Subject: Re: [Fwd: Re: [Homebrew_PCBs] Re:Sprayer pressure]

From: "Stefan Trethan" <stefan_trethan@...>
Date: 2005-03-15

On Tue, 15 Mar 2005 12:05:40 -0500, uhmgawa <uhmgawa@...> wrote:

>
> Alternatively to avoid intricate pump components having
> to withstand etchant corrosion it would be possible to
> use compressed air to pressurize a container of etchant
> located below board tank level. This again is not 100%
> duty cycle as the etchant must be allowed to gravity
> backflow to the etchant container when said container
> becomes empty. Achieving this could be as simple as locating
> a check valve in the backflow line and bleeding off the
> air pressure in the etchant container. The only thing
> required to automate the process is a float switch in the
> etchant container and a solenoid air valve to alternatively
> pressurize/bleed air to/from the etchant container.


Had the same idea a few days ago. However, will try rotational etcher
first.
Nozzles need quite a lot of volume.

ST