[sdiy] solder types

[Grant Richter]

> This type of solder flux HAS to be cleaned as it has a slightly acidic
> base which will "dull" the solder joints a bit if left on too long. Some
> folks say clean every three hours. I would definitely clean if it is
> going to be overnight. Finish off the cleaning job with some distilled
> or deionized water from a spray bottle.
> 

I started a prototype board with Hydro X solder. I got interrupted and
forgot about it. When I came back a month latter, the Hydro X had eaten away
the traces (12 mil, 1 ounce) going to the pads. They were disconnected!

So Hydro X is great, but it must be cleaned within a few hours. I wouldn't
leave it on overnight, it MIGHT start to thin traces.