Homebrew PCBs

----- Original Message ----- 
From: "Peter Johansson" <peter@...>
To: <Homebrew_PCBs@yahoogroups.com>
Sent: Thursday, March 10, 2005 7:22 PM
Subject: Re: [Homebrew_PCBs] Re: bubbler - more even spread of bubbles


>
>
> Phil writes:
>
>> I'm thinking of going to a mechanical agitator to move the board up/dn
>> but have no idea if it will work well.  I figure something around 100
>> hz to start with.
>
> I'm a newbie to the group.  The last time I etched a board was perhaps
> 20 years ago masked with an etch-resistant pen.  I've been mostly a
> software guy since then, but I'm getting back into hardware as a
> hobby.  So, my appologies in advance if this is old news...
>
> Here's a thought on agitation:  Find a gear motor that runs somewhere
> arround 30 RPM.  Mount a disc perhaps 2-3 inches in diameter with an
> offset center to the motor.  Mount underneath one edge of the tray.
> Might something like this do the trick?

Something like that was in the ARRL Handbook a few years ago. A heat lamp 
mounted above the etchant container kept the solution hot.

Leon