Archive of the former Yahoo!Groups mailing list: Homebrew PCBs

----- Original Message -----
From: "Stefan Trethan" <stefan_trethan@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Thursday, April 08, 2004 1:09 PM
Subject: [Homebrew_PCBs] horizontal etch - bottom side way faster


>
>
> Hi
>
>
> just want to inform you that the bottom side is etched MUCH faster in a
> horizontal etch
> setup.
>
> HCl H2O2, from time to time moving the container around to agitate.
>
> at least half the time on the bottom side, the top just starts
> to clear at the edges and the bottom is already clear..
>
> i assume it is because the etched away stuff is heavy, and sinks away from
> the bottom
> while it deposits on the top...
>
> so if you do single sided board do them face down,
>
> this is bad for doublesided, because of underetching....
>
> i start thinking a vertical setup might really have been a better idea..
>
> any good ideas out there for a vertical tank pcb holder?

Simplest way is to put a piece of string in a hole in the board and dangle
it in the tank.

Leon

Leon