Homebrew PCBs

On Thu, 08 Mar 2007 01:22:50 +0100, Ted Bruce KX4OM <kilocycles@...>  
wrote:

>
> The problem I still have is fibers from the paper remaining in the
> space between the tracks.  It amazes me that loose single fibers can
> act as a resist, leaving copper wisps on the board after ferric
> chloride etching.  I usually either scan the board at 600 DPI, or go
> over it with a loupe after etching to check for shorts.


Try wiping it wet with a piece of foam rubber. The cell structure seems to  
grab hold and pull such fibers away very well.
I would expect polyurethane kitchen sponges might work too, but i only  
tried the plain green springy foam rubber. Avoid anything that might  
lubricate the fibers to slip through the foam, like detergent.

ST