Homebrew PCBs

Markus Zingg wrote:

> Hi Adam
> 
> 
>>What small copper wires are you talking about ?
> 
> 
> Good question :) That's what someone told me they are used for. Well,
> I used the station during some runs without those bags and could not
> see a difference in the results. There are also no visible wires or
> such, so maybe they surf another purpose - hell, most likely the one
> you describe.
> 
> I also use brigthner and the anodes also became this dark "patina"
> which I was told is good/important for the process. I do have the bags
> mounted and since I have them I never felt motivated to try without.
> Might be that I under estimate their effect. I must say though that I
> don't use air agitation in my tanks.
> 

The brightener data sheet describes the optimum color for 
anodes and black to very dark brown. If red or pink then it 
means something is out of balance. Oh, one more thing, this 
dark film only forms on phosphorized copper anodes (copper 
with 0.05% phosphorous). Without the phosphor there is no 
film and the anodes dissolve in such a way they release 
copper powder in the solution. I think its the additives 
that are mostly responsible for making the copper anodes 
dissolve this way. I know from early experiments copper 
plating with a low acid high copper plating solution (75g/L 
H2S04, 200g/L CuSO4.5H20) without additives and pure copper 
anodes then the anodes dissolve reasonable cleanly.

A beginner might like to use that bath instead because no 
brightener or phosophorized anodes are needed. Problem with 
this bath is that plating uniformity is extremely sensitive 
to your anode configuration. Also  you can only plate to 
about 100 um before copper "noodles" start forming.