Homebrew PCBs

On Wed, 09 Mar 2005 21:37:25 -0000, Phil <phil1960us@...> wrote:

>
> One I had was a blue tube say 2 cm diameter and 3-4 cm long. It felt
> hard but brittle.  I thought it was some sort of foamed glass but when
> it fell apart it was clearly some sort of plastic.  It turned white.
> I still have some bits of it floating in my etchant...
> The other one was grey and some what like foam.  definitely plastic of
> some sort.  It lasted only slightly longer.
> Do you need bubbles or agitation?  These days I just let the end of
> the air hose dangle in the etchant and the pressure causes it to go
> back and forth giving me enough stirring so the etch is reasonably even.
> Phil


Damn, and thank you for that post.
I almost bought one of the hard/brittle variety just now.
(two of 3 ebay sellers have relpied within 5 minutes, one is as we talk  
the hard and brittle variety and the other doesn't know the material, but  
it is a flexible porous hose so plastic.)

I really thought the hard/brittle type would work and i'm done with it....
Back to the drawing board then.

I want the air to mix the etchant, but also to help agitate the etchant  
right at the board, now i see much faster etching in the streaks where the  
bubbles rise.


ST