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Subject: Re: [Homebrew_PCBs] Re: etch tank idea

From: Adam Seychell <a_seychell@...>
Date: 2008-04-30

garydeal wrote:
> Then the question is whether it would do the same in a vertical
> configuration, as I need to accomplish two-sided etching. hmmm. =8/
>
> -Gary
>

It still might be possible to understand bubble etching enough to build
a tank that etches uniformly. I'm suspecting the tank needs to be wide
enough so the return fluid can flow downward unimpeded by rising
bubbles. That effect won't happen in a narrow tank. It might have to be
4" (100mm) wide.

I'm thinking the bubbles should distributed evenly across the side walls
of the tank rather than directly under the PCB. Downward fluid flow
would occur in the centre where the PCB is located.


| |
|~~~~~~~~~|
|o o|
|o | |
| | o|
|o P o|
| C |
|o B o|
| | |
| | o|
|o o|
| |
|o_ _o|
|[ ] [ ]|
'---------'

<- 100mm ->