Homebrew PCBs

I'm about to try the Sulfamic acid one.  I also got the chemicals on EBay.  I'll let you know.


--- In Homebrew_PCBs@yahoogroups.com, Larry Battraw <lbattraw@...> wrote:
>
> > > > I have very good luck with elctroless tin. The formula I use came from the September 1971 issue of Ham Radio magazine.
> > > >
> > > > .5g Stannous Chloride
> > > > 2.0g Thiourea
> > > > 3.0g Sulfamic Acid
> > > > 100.0 mL Distilled water
> > > >
> > > > The solution is ued cold, I never tired heating it. It plates up in a few minutes and does a goog job but can't be use as a resist for further etching. The solution does not keep and I always make up a fresh batch for each board making session. I would usually mix up less than 100 mL depending on the size and number of boards I was doing.
> > > >
> > > > Craig
> 
> Has anyone else tried this?  I ordered the chemicals off eBay and
> tried it with sulfamic and sulfuric acid (separate times) and it does
> not seem to work.  I was very careful measuring, used distilled water,
> and cleaned the copper with sandpaper so it was completely exposed.
> The recipe using sulfuric came from here:
> http://www.finishing.com/0200-0399/260.shtml
> 
>  The only thing I can think of is that the Stannous Chloride I have is
> not actually what it seems to be since it's the only thing I haven't
> been able to substitute something else for.  I tried a recipe for
> electroplating which uses Stannous Chloride and Hydrochloric Acid and
> also had no luck-- it turned the copper I was trying to plate black.
> Perhaps I have Stannic Chloride?  I have no idea how they differ.
> 
> Thanks-
> Larry Battraw
>