Wow, what a helpful string. Not surprised as soldering’s our spooky zone, wildly dynamic and complex. So, my experience has told me that after developing a “touch and feel” for my torches and metals and fitting my surfaces flush, not casual flush, serious flush, then cleaning my elements well, I continued to have inconsistent outcomes. Things improved dramatically when I examined my standards of clean and quickly realized how crucial this soldering step is. Oxidized solder with body oils on it, dirty flux, metal that doesn’t clearly shed water will compromise my efforts. Cleaning parts is relatively easy, just make sure it sheds water without pooling on the surface. Ultimately, I found I was taking the solder too much for granted. So now I carefully strip clean all of my solder with sandpaper and a green fiber scrub with detergent and always snip clean fresh pallions. I don’t touch any cleaned solder with my fingers. I keep my flux protected from contamination and I suppose preparing fresh flux for each soldering job is ideal. As overkill I thin flux with distilled water to avoid increasing its minerality over time. Once I made sure that last little cleaning step on the solder was done scrupulously and flux was clean my solder flowed faster and more evenly with rare problems, no matter the other technical issues. Clean solder’s less likely to ball up and freeze, allowing a little more wiggle room as the heat burns up the flux and the different elements are heating unevenly. My final contribution comes from my teacher who often said to remember that flux is my friend, don’t skimp. That’s the point isn’t it? Get the solder to flow before your flux fries and the bezel does too.
Thanks for bringing this up.
I use 18k gold bezels on silver with 14k gold solder. The solder flows well below the melting point of both the gold and silver.
Now I need to be sure that I’m not coating my bezel with 14k solder.
I think I’ll try with a a solder resist on one spot on the bezel so I can see if that’s the case.