Copper/Soldering Question

All,

Made an IC and a sparge ring from copper over the last week. Both have fittings I sweated on that will contact the wort/water. Used lead-free flux and lead-free silver solder. When soldering these on, I made sure to try to only heat the fitting, not the pipe. Nonetheless, the pipe had some greyish-green splotching when I was done as a result of all the heat. In all cases, I sanded the hell out of the joints after I was done, and was able to remove most of this splotching, while just scratching up the solder.

Question is, by (a) scratching up the outside of the pipe so much and (b) scratching up the solder after it was set, am I now going to leech harmful stuff into my wort/mash from where the exposed, scratched surfaces contact it?

Thanks - Norm

I dont know about any of that. I do know if you let the joint cool slightly (about 3-4 mins) and then apply some flux to the entire fitting. Then heat slightly and slowly the "green splotches" will be able to be removed with a towel or brown jersey gloves. A vinegar/salt boiling also helps.
I used 2 gals standard vinegar, 2 cups salt and 4.5 gals of water in my brew kettle. That cleaned everything up great.

I don't think you have anything to worry about. The green you see is the effect of the flux. I used non lead silver solder also and a non-toxic flux that has a citric acid base.

Norm, first off, the green was only oxidized copper. Sanding the joint won't hurt the copper, nor the solder, especially if you used silver solder, and not just regular lead-free solder. I haven't brewed my first batch yet, but think about this: in most homes, water is delivered to the tap through copper pipes that have been sweated together via lead-free solder.

Thanks guys. Good news.

you could soak in some StarSan to brighten / sanitize. It works great on my chiller

I use only fair traded, free ranging, organic flux and sterling silver solder. Why settle for anything less?

Excellent - love that free-ranging flux, but my sterling solder supply has dried up in recent months!

You can substitute gold in a pinch. I once used my old wedding ring and it made the absolute best solder joints. The glint of the gold showing on the chiller fittings really set it off nicely. I was worried that the ring made of only 14 carat gold would not be pure enough, but the worry proved to be unfounded.