What is leaching out of my solder? (Pics)

[Bobbywolf]

For my 3" Boka, I use small marbles as packing, retained by a copper end plate that is drilled and has copper bars soldered to prevent marbles packing and plugging the holes. The solder used was "Oatey Safe Flo Lead Free Solder" pn 53062.

Luckily, I took photos of when I built it, roughly 1 1/2 years ago, and here it is present day, with lots of runs through it.

Before

Before

After

After


From what I understand, many of the members here built their stills using this solder, myself included. However, the solder is eroding away over use, likely leaching something into my boiler, and possibly even my product. I can not tell any change in taste or anything offputting because of this. As far as I can tell, this is limited to this retainer plate, and the solder joints in the still itself have not eaten away like this. Could this be because it is directly on top of the boiler, in contact with the boiling wash?

Does anyone else have solder directly in line with their vapour path and have pitting like this?

[StillerBoy]

From observation of the pictures, the original build shows lots of what is called cold soldering, in other words, the solder was melted instead of allowing it to flow, by heating the solder hotter that the material being soldered, you can crystallize the solder thereby overtime it will weaken the solder.. so after a period, 1.5 yrs of regular usage, you have develop whats in the second picture..

I would try to reheating the joint, by adding some paste, using a very small flame or iron, and should be good as new..

This link shows what the difference are of proper soldered joints..https://learn.adafruit.com/adafruit-gui ... n-problems" onclick="window.open(this.href);return false;" rel="nofollow

Mars