Simao,
Having all the chemicals (3) in dry form is the advantage over other prepackaged liquid plating systems. You just mix up what you need for the number of boards you are doing. No worry that your 1 year old bottle of tin plating solution is bad or you have used up all the Tin content. You mix fresh batch each time and you know how much tin chloride is remaining in your supplies. Its simple to mix with just a measuring spoon. Disposal is tha same problem in either case. I either evaporate the solution or save it in a container for disposal at my city's toxic disposal day.
Craig
--- In Homebrew_PCBs@yahoogroups.com, Simao Cardoso <simaocardoso@...> wrote:
>
>
> Six month ago people were complaining that MG chemicals Liquid tin is
> too expensive. This mixture is more expensive, harder to use and useless
> for making boards from time to time.
>
> I really don't advise people to buy those chemicals, one won't like
> results one month after mix. Mixing it every time one do pcb's is
> boring, and think about disposal the used stuff.
> But at least use the tin sulphate, sulphuric acid and thiourea mix. Less
> hazard and easier to get. The tin salts can be home made. There are
> metal cleaners with thiourea but too expensive.
>
> I have a bunch of chemicals including those, my advise? Buy Mg Chemicals
> liquid tin. From what i learn is the best, good price, easy to store and
> long lasting. This group is mostly North American people should be easy
> to get there. I really wish to be able to buy it anywhere in Europe. (I
> know, they have a representative in France).
>
> There are from MegaUK and Ormecon equivalent products but based on
> methane suphonic acid, by what i know should be as long lasting as
> fluoroboric mix or better but the only number given is 6 months life.
> Ormecon is now part of Enthone, which is well represented everywhere.
> But since i have thiourea, one day i will asking around at tin plating
> facilities if they sell me for cheap, some of their suphonic or
> fluoboric tin electroplating solution, mix thiourea in it, and hope it
> last for a few years.
>