Homebrew PCBs

grantfair2001 wrote:
> Hi Adam-
> 
> I took the lid off the tank as planned 2 nights ago. By noon today I
> saw little change. The etchant was clear, the copper wire in the
> etchant was shiny and looked just as it did before it went in, and the
> wire above the etchant surface is a bit more covered with a cloudy
> film a bit darker shade of copper than the shiny wire. There was a bit
> more blue stuff on the copper, but this might cover 5% at most.

Thanks for letting us know what's happening. I don't remember it 
being that slow, I think the solution goes dark in 1st 2 days. 
But I'm testing the process more thoroughly to find out more. I'm 
not sure why it seems to not be working for you. Maybe I should 
of been 110% sure of my self before giving out instructions. 
There's no need to buy a hydrometer or any more expensive 
glassware just yet. I haven't worked out the optimum density 
range yet. I would hate for to buy anything becasue of my 
recommendation and find out later that it was not needed or the 
worng item.

The H2O2 will get things moving along. try bubbling air through 
the soltuion for a few hours and see what color change to the 
solution. If you see white film form on the copper that can 
easily wash off then thats copper(I) chloride. The blue stuff is 
copper (II) hydroxide and will dissolve in the excess HCl 
instandly to form copper(II) chloride.