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
--- In Homebrew_PCBs@yahoogroups.com, Alessio Sangalli <alesan@...> wrote:
>
> Hi, as I am perfectioning my PCB making, I reached a point where I can
> do very good boards, but especially if I am making a bigger, double-face
> one, with huge ground planes, tinning takes simply too much time, and if
> I want to do it properly, I end up wasting a lot of solder wick braid to
> remove the excess tin.
>
> I've read past messages but I was not able to find a method that is well
> documented and can be considered a viable solution for a hobbyst that
> makes only few boards per month.
>
> bye
> as
>