I primarily used Ferric Chloride and you are correct, if handled properly, it is not too bad. But we have all kinds of local bylaws now about disposing of it and as I live in a Flat I don't really have the space to store and mess with chemicals. On the other hand, professionally made PCB's are a lot more affordable these days, not cheep, but if it is for a final project, especially if you need to make more than one unit, possibly to help defray the cost, PCB services can do it well and reasonably fast even down to very fine pitch and include through hole plating and silk screening that are virtually impossible with home etched boards. Cheers Chris On 2 January 2012 06:09, Sean Breheny wrote: > Hi Chris, > > Which chemicals are you talking about? The only two common ones I know > of are Ferric Chloride and Ammonium Persulfate. Neither are any more > toxic than common household chemicals as far as I know. Ferric > Chloride is generally considered nasty because of its ability to stain > things permanently, but as long as you dilute it sufficiently, it > should be disposable in a municipal sewer system - indeed, it is > sometimes used in wastewater treatment I think. I am less familiar > with Ammonium Persulfate but I doubt that it is any worse. > > Sean > > --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .