Larry,
Glad the tin formula worked out for you, I did lots of boards with it. Looks like you have a nice PCB processing setup. Your hole activation and plating video for plated throuch holes was interesting. After the copper plating, I assume you re-image the board with new dry film then etch. How do you make sure you don't etch out the holes you just plated? Is the dry film strong enough to tent all the holes or do you use a tin/lead process?
Craig
--- In Homebrew_PCBs@yahoogroups.com, "fredbutz" <fredbutz@...> wrote:
>
> Well I tried it.
> Worked great for me. I made a video and will post it tomorrow afternoon.
> me
>
> --- In Homebrew_PCBs@yahoogroups.com, "fredbutz" <fredbutz@> wrote:
> >
> > 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
> > >
> >
>