tsb wrote:The new enviro solder and flux sucks. ( had a leak after 6 months )
Yes, it does suck! I thought I'd be able to find regular 50/50 solid core solder somewhere, but I couldn't, caved, and bought the lead-free stuff. I will say that the latest solder I bought isn't TOO bad - it says it works as easy as the "old school" solder, which it doesn't, but it is a metric butt-load better than the original unleaded stuff. I ran out of the solder I bought with about 4 fittings to go so I grabbed a little spool I've had for at least 10 years. OMG, I about melted the copper in half! This older solder has a melting range that seems to be about 2 degrees. Too cold - it won't flow, too hot - it won't flow. You have to get it JUST right. On 1" copper it's not too bad, but on 1/2" you might as well just set yourself on fire.
I said "fck this" and grabbed my spool of 60/40 rosin core electronic solder and finished the job (still using the plumbing flux as usual). WOW, what a difference!!! I've never sweat copper with "leaded" solder, but now I'm REALLY wishing I'd found (or ordered) some 50/50 solder. Good GOD, it practically solders itself! Get the joint in a general range of hot, all clean and fluxed, and the solder almost unrolls itself and jumps into the joint. If you don't watch it, the solder will try to tin the entire length of pipe and do the next joint for you! And to top it off, you've got plenty of time to get a wet rag and polish off the joint for a shiny, slick appearance.
Word to the wise - do yourself a huge favor and go buy some real solder for sweating together hydronic system copper. The "big box" stores don't sell it as far as I can tell. McMaster-Carr is your friend - order some Kester 50/50 and be done with it.