Homebrew PCBs

--- In Homebrew_PCBs@yahoogroups.com, "Andrew Mawson" <andrew@m...> 
wrote:
<snip>

> a/ should it be distilled or tap water?

Several possibilities come to mind:

It's possible that your local tap water may contain minerals or 
other impurities which could prevent the resulting solution from 
working correctly. 

The working life of the solution may be extended by using distilled 
water.

> b/ what is the odd chemistry that lets it work at room  temp but 
> not at 50 Deg C when increasing the temp normally speeds up 
> chemical reactions.

If what you're dissolving is a mixture of dry chemicals, the water 
may need to be heated to get all of the components dissolved 
properly. Depending on the chemicals in the solution, its action may 
be more stable at a lower temperature.

Personally, I'd follow the manufacturer's recommendations unless I 
had some assurance that any changes weren't going to cause 
unforeseen problems. YMMV, of course.

Regards, Bob