Homebrew PCBs

PC Board group and "DJ Delorie" dj@...  
      <mailto:dj@...?Subject=%20Re%3A%20Old%20GL%20FeCl%20-very%20slow%20%20etching%20copper>


Thank you for info!!!!!!!!

> FeCl would normally be a light or dark tan color. Black or green means
> it's spent. The cheapest thing to try is to add some hydrogen peroxide
> to it, which will convert some or all of the dissolved copper into a
> cupric chloride etchant (emerald green). 

   I have several bottles of 3% hydrogen peroxide. Will 3% work or do I 
need to buy 10% or stronger?
> If that doesn't work, you'll
> have to add some hydrochloric acid, effectively making an acid/peroxide
> etchant that happens to have some spent FeCl in it.
    Ok.
>
> I've used old etchant that wasn't spent and it works just fine; it's not
> the age that counts it's how much you've used it.
     Never used my FeCl very much. Is a mystery why my solution is in 
this condition.
Many thanks for suggestions.
Dave_s