Homebrew PCBs

Adam Seychell wrote:
> 
> rolanyang wrote:
> 
>>Do you have a digital camera? Can you take a photo
>>of your solution? When you have something that looks
>>like http://www.techfreakz.org/cucl2/?slide=5
>>the solution is probably right.
>>
>>If you're getting brown or sludge, then first bubble
>>air through it or add H2O2. If that doesnt help, then
>>start adding HCl until it turns blue-greenish.
>>
>>Adding too much HCl won't slow down the reaction
>>but not having enough CuCl2 will.
>>
>>Here's another idea: 
>>does anyone know if copper powder is cheap?
>>The reaction would likely go a lot faster
>>since the suface area of powder is drastically
>>greater than when using plain old scrap wire
>>or boards.
>>
> 
> You can get copper powder from some art supplies, but its VERY 
> expensive for what we are doing. I think they use it as pigments 
> in paint, or coating surfaces. Its almost fine as flour and thus 
> dangerous to breath in.
> 
> You can react either, copper carbonate, copper(II) oxide (black 
> pigment powder) or copper(II) hydroxide (bright blue powder for 
> fungicides) with HCl and instantly get copper(II) chloride 
> solution. The problem is none of these are easily/cheaply 
> available as scrap copper in the quantities we need (1 kg of 
> copper). Maybe they are, but I don't know of any.
> You can get few hundred grams at very high $/kg or buy 25 kg bag 
> from an industrial supplier at low $/kg but you'll have *way* to 
> much. Unfortunately there is no in-between.
> 
> I'm going to have a better play around with getting copper metal 
> to react with HCl and do it fast as possible.

I bet it's been tried, but does this work: CuSO4 + 2HCl -> CuCl2 + H2SO4
CuSO4 is in garden shops.